C14Temp&ProcessRefInfo0604

R E F E R E N C E I N F O R M A T I O N

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Configuration Example of Temperature ControlThe following is an example of the configuration of temperature control.

Relay output Voltage output Current output

SSR Cycle controller Power controller

Thermocouple Platinum resistance thermometer Thermistor Infrared non-contact sensor

TemperatureController

Control signalController

Controlled object

Temperature Sensor

The Temperature Sensor consistsof an element protected with apipe. Locate the element, whichconverts temperatures into electricsignals, in places wheretemperature control is required.

Electronic Temperature Controller

The Electronic Temperature Controlleris a product that receives electric signalinput from the temperature sensor,compares the electric signal input withthe set point, and outputs adjustmentsignals to the Controller.

Controller

The Controller is used to heat up orcool down furnaces and tubs using adevice, such as a solenoid or fuel valve,to switch electric currents supplied toheaters or coolers.

Temperature ControlThe set point is input into the Tempera-ture Controller in order to operate theTemperature Controller. The timerequired for stable temperature controlvaries with the controlled object. Attempt-ing to shorten the response time willusually result in the overshooting orhunting of temperature. When reduce theovershooting or hunting of temperature,the response time must not be short-ened. There are applications that requireprompt, stable control in the waveformshown in (1) despite overshooting. Thereare other applications that require thesuppression of overshooting in thewaveform shown in (3) despite the longtime required to stabilize temperature. Inother words, the type of temperaturecontrol varies with the application andpurpose. The waveform shown in (2) isusually considered to be the best one forstandard applications.

1. The temperature stabilizes afterovershooting several times.

Time

Temperature

2. Proper response

Time

Temperature

3. The response is slow in reachingthe set point.

Time

Temperature


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Characteristics of the Controlled ObjectBefore selecting the Temperature Controller and Temperature Sensor models, it is necessary to understand the thermal characteristics of thecontrolled object for proper temperature control.

Characteristics ofcontrolled object

Heat capacity

Staticcharacteristics

Dynamiccharacteristics

Externaldisturbances

Heat capacity, which indicates the degree of ease ofheating, varies with the capacity of the furnace.

Static characteristics, which indicate the capability ofheating, vary with the capacity of the heater.

Dynamic characteristics, which indicate the startupcharacteristics (i.e., excessive response) of heating, varywith the capacities of the heater and furnace that affecteach other in a complex way.

External disturbances are causes of temperaturechange. For example, the opening or closing of the doorof a constant temperature oven will be a cause ofexternal disturbance thus creating a temperaturechange.

J ON/OFF CONTROLACTION

This is the simplest form of electroniccontrol, usually used in the least expen-sive controllers. As shown in the graphbelow, if the process value is lower thanthe set point, the output will be turnedON and power will be supplied to theheater. If the process value is higher thanthe set point, the output will be turnedOFF with power to the heater shut off.This control method is called ON/OFFcontrol action, in which the output isturned ON and OFF on the basis of theset point to keep the temperatureconstant. In this operation, the tempera-ture is controlled with two values (i.e.,0% and 100% of the set point). There-fore, the operation is also called two-position control action.

Characteristics ofON/OFF control action

Setpoint

Heater

Hysteresis

Time

J P ACTION

For more stable control, it is necessary toslow down the rate of temperature risewhen approaching the set point in orderto avoid overshoot. By modifying theON/OFF switching pattern, the peaksand troughs are smoothed out, thusmaintaining a stable temperature. Paction (or proportional control action) isused for obtaining the output in propor-tion to the input.

The Temperature Controller in P actionhas a proportional band with the set pointin the proportional band. The controloutput varies in proportion to the devi-ation in the proportional band. In normaloperation, a 100% control output will beON if the process value is lower than theproportional band. The control output willbe decreased gradually in proportion tothe deviation if the process value iswithin the proportional band, and a 50%control output will be ON if the set pointcoincides with the process value (i.e.,there is no deviation). This means Paction ensures smooth control withminimal hunting compared with theON/OFF control action.

Proportionalcontrol action

Setpoint

Proportional band

Temperature

Controloutput

Example:

If a Temperature Controller with a tem-perature range of 0 to 400C has a 5%proportional band, the width of the pro-portional band will be converted into atemperature range of 20C. In this case,provided that the set point is 100C, a fulloutput is kept turned ON until the pro-cess value reaches 90C, and the outputis OFF periodically when the processvalue exceeds 90C. When the processvalue is 100C, there will be no differ-ence in time between the ON period andthe OFF period (i.e., the output is turnedON and OFF with the same interval).

Controloutput

Setpoint

A narrow proportionalband is set.

A wide proportionalband is set.

Set point

A narrow proportionalband is set.

Time

Offset

A wide proportionalband is set.


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J I ACTION

I action (integral control action or reset)helps to achieve control at the set pointand is used for obtaining the output inproportion to the time integral value ofthe input.

P action causes an offset. Therefore, ifproportional control action and integralcontrol action are used in combination,the offset will be reduced as the timegoes by until finally the control tempera-ture will coincide with the set point andthe offset will cease to exist.

Time

Offset

Offset ceasesto exist.

PI (proportionaland integralcontrol) action

P (proportionalcontrol) actiononly

Setpoint

Controloutput

Setpoint

A long integral time is set.

A short integral time is set.

Time

Time

A short integral time is set.

A long integral time is set.

J D ACTION

D action (derivative or rate control action)is used for obtaining the output in propor-tion to the time derivative value of theinput. It provides a sudden shift in outputlevel as a result of a rapid change in ac-tual temperature.

Proportional control action corrects theresult of control and so does integralcontrol action. Therefore, proportionalcontrol action and integral control actionrespond slowly to temperature change,which is why derivative control action isrequired. Derivative control action cor-rects the result of control by adding thecontrol output in proportion to the slopeof temperature change. A large quantityof control output is added for a radicalexternal disturbance so that the tempera-ture can be quickly in control.

Controloutput

Externaldisturbance

PD (proportionaland derivativecontrol) action

Time

Time

A long derivative time is set.

A short derivative time is set.

Setpoint

P (proportionalcontrol) actiononly

A long derivative time is set.

A short derivative time is set.

Time

Setpoint

J PID CONTROL

PID control is a combination of propor-tional, integral, and derivative controlactions, in which the temperature iscontrolled smoothly by proportionalcontrol action without hunting, automaticoffset adjustment is made by integralcontrol action, and quick response to anexternal disturbance is made possible byderivative control action.

PIDcontrol

J ADVANCED PIDCONTROL

Conventional PID control uses a singlecontrol block to control the responses ofthe Temperature Controller to a targetvalue and external disturbances. There-fore, the response to the target value willoscillate due to overshooting if impor-tance is attached to the response to ex-ternal disturbances with the P and I pa-rameters set to small values and the Dparameter set to a large value in the con-trol block. On the other hand, if impor-tance is attached to the response to thetarget value (i.e., the P and I parametersare set to large values), the TemperatureController will not be able to respond toexternal disturbances quickly. It will beimpossible to satisfy both the types ofresponses in this case.Advanced PID control eliminates thisweakness while retaining the strengths ofPID control, thus making it possible toimprove both types of responses.

PID Control

Response to the target value will becomeslow if response to the external distur-bance is improved.

Response to the external disturbance willbecome slow if response to the target val-ue is improved.

Advanced PID Control

Response totarget value

Response toexternal disturbance

Controls both the target value responseand external disturbance response.


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J PID WITH FUZZY CONTROL

By adding fuzzy control to PID control,further improvement in response to externaldisturbances is possible. PID and fuzzycontrol usually operate as PID control. Ifthere is external disturbance, fuzzy controlwill operate in combination with PID control.

OMRONs fuzzy control estimates tempera-ture change from the difference betweenthe deviation (i.e., the difference betweenthe set point and process value) anddeviation change rate, and then makes thedelicate adjustment of the control output.

Setpoint

PID control

Externaldisturbance

PID and fuzzy control

An increase in output. Suppresses theoutput to eliminateovershooting.

Control on the basis of the deviation and deviation change rate.

Response to the target value.

PID control

Response to external disturbance

PID and fuzzy control


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Topical Reference

J SECTION ORGANIZATIONThe following Topical Reference dis-cusses how Omron controls perform ineach critical aspect of a temperature orprocess control system. The sections aredivided into these categories, then pre-sented in alphabetic order

Control Alarm Temperature Sensor Output Setting

This glossary does not address the manyterms commonly used in general industri-al control.

ControlJ ANTI-RESET WINDUP

(ARW) FUNCTION

ARW stands for anti-reset windup. Thisfeature reduces or eliminates excessiveReset (Integral action) error created inresponse to the steep rise to the initialtemperature set point. There is usually alarge deviation (i.e., a large differencebetween the process value and set point)when the Temperature Controller startsoperating. Integral control action in PIDcontrol is repeated until the temperaturereaches the set point. As a result, anexcessive integral output causingovershooting is output. To prevent this,the ARW function sets a limit to restrictthe output rise in integral control action.In normal control operation, the integraloutput is eliminated until the processvalue reaches the proportional band.

Setpoint

Proportional band

Overshooting due toexcessive integral output.

Deviation

Time

Time

Integraloutput

Initial integral output withARW function disabled.

Initial integraloutput with ARWfunction enabled.

Temperature ordeviation

J CONTROL CYCLE AND TIME-PROPORTIONING CONTROL ACTIONThe control output will be turned ON in-termittently according to a preset cycle ifP action is used with a relay or SSR.This preset cycle is called control cycleand this control method is called time-proportioning control action.

Temperature

Setpoint

Proportionalband

Actualtemperature

The higher the temperature is,the shorter the ON period is.

T: Control cycle

Control output =TON

TON + TOFFx 100 (%)

TON: ON periodTOFF: OFF period

Example;If the control cycle is 10 s with an 80%control output, the ON and OFF periodswill be the following values.TON: 8 sTOFF: 2 s


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J CONTROL OUTPUT

Controloutput

ON/OFF output

Linear output

Contact relay output used for control methodswith comparatively low switching frequencies.

Non-contact solid-state relay output for switching1 A maximum.

Relay output

SSR output

ON/OFF pulse output at 5, 12, or 24 VDCexternally connected to a high-capacity SSR.

Voltage output

Continuous 4- to 20-mA or 0- to 20-mA DCoutput used for driving power controllers andelectromagnetic valves. Ideal for high-precisioncontrol.

Current output

Continuous 0 to 5 or 0 to 10 VDC output usedfor driving pressure controllers. Ideal forhigh-precision control.

Voltage output


E--8

Control Output Connection Example Using Voltage Output to Drive SSRs

Electronic Temperature Controller

Voltage outputterminals fordriving SSR

Directly connectable

Load

HeaterLoad power supply

Temperature Controller at 12-VDCOutput with 40 mA

E5jJ(Excluding E5CJ)

E5jK(Excluding E5CK)

E5AN, E5EN


E5CS-X

E5CN, E5GN

E5CJ

E5CK


E5ZE


E5C4

G3PA-VD at 240-V outputwith 10, 20, 40, or 60 A

Rated input voltage:5 to 24 VDC

Subminiature, slim model with amono-block construction andbuilt-in heat sink

5 (8)

3 (4)

3 (4)

1 (2)

Number of SSRsconnectable in parallel

Values in parenthesesindicate 400 V models.

G3NH with 75 or 150 A

5 to 24 VDC

Ideal for high-powerheater control

8

4

4

2

G3NA at 240-V outputwith 5, 10, 20, or 40 A, at480 V with 10, 20, or 40 A

5 to 24 VDC

Standard model withscrew terminals

5 (8)

3 (4)

3 (4)

1 (2)

G3NE with 5, 10, or 20 A

12 VDC5 VDC

Compact, low-cost modelwith tab terminals

2

1

1

G3B with 5 A

5 to 24 VDC

Fits standard 8-pin round socket,offers 5 A switching current

5

2

6

3

Values in parenthesesindicate 400 V models.


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J DERIVATIVE TIMEDerivative time is the period required fora ramp-type deviation in derivativecontrol (e.g., the deviation shown in thegraph at right) to coincide with the controloutput in proportional control action. Thelonger the derivative time is, the strongerthe derivative control action is.

PD Action and Derivative Time

Deviation

Controloutput

PD action(with a short derivative time)

PD action(with a long derivativetime)

P action

D2 action

D1 action

TD: Derivativetime

(with a shortderivative time)

(with a long derivative time)

J FUZZY SELF-TUNINGPID constants must be determinedaccording to the controlled object forproper temperature control. The conven-tional Temperature Controller incorpo-rates an auto-tuning function to calculatePID constants, in which case, it will benecessary to give instructions to theTemperature Controller to trigger theauto-tuning function. Furthermore, if thelimit cycle method is adopted, tempera-ture disturbance may result. The Temper-ature Controller in fuzzy self-tuningoperation determines the start of tuningand ensures smooth tuning withoutdisturbing temperature control. In otherwords, the fuzzy self-tuning functionmakes it possible to adjust PID constantsaccording to the characteristics of thecontrolled object.

Fuzzy Self-tuning in 3 Modes

PID constants are calculated by tuningat the time of change in the set point.

When an external disturbance affectsthe process value, the PID constantswill be adjusted and kept in a specifiedrange.

If hunting results, the PID constants willbe adjusted to suppress the hunting.

Auto-tuning Method of aConventional TemperatureControllerAuto-tuning Function: Automaticallycalculates the appropriate PID constantfor controlling objects.

Features:1. Tuning will be performed when the

AT instruction is given.

2. The limit cycle signal is generatedto oscillate the temperature beforetuning.

Targetvalue

ATinstruction

AT starts.

Temperatureoscillated.

PID gaincalculated.

Self-tuning FunctionSelf-tuning (ST) Function: A function toautomatically calculate optimum PIDconstants for controlled objects.

Features:1. Whether to perform tuning or not is

determined by the TemperatureController.

2. No signal disturbing the processvalue is generated.

Targetvalue

ST starts.

PID gaincalculated.

Temperaturein control

Temperaturein control

Externaldisturbance 1

Externaldisturbance 2

J HUNTING AND OVERSHOOTINGON/OFF control action often involves thewaveform shown in the following graph.A temperature rise in excess of the setpoint after temperature control starts iscalled overshooting. Temperature oscilla-tion near the set point is called hunting.Improved temperature control is to beexpected if the degrees of overshootingand hunting are low.

Hunting and Overshooting in ON/OFFControl Action

Overshooting

Hunting

Setpoint


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J HYSTERESIS

ON/OFF control action turns the outputON or OFF on the basis of the set point.This means the output frequentlychanges according to minute tempera-ture changes, which shortens the life ofthe output relay or unfavorably affectssome devices connected to the Tempera-ture Controller. Therefore, a temperatureband is created between the ON andOFF operations. This band is called hys-teresis.

HysteresisD: Hysteresis

Temperature

Controloutput

Example:

If the Temperature Controller with atemperature range of 0C to 400C has a0.2% hysteresis, D will be 0.8C.Therefore if the set point is 100C, theoutput will turn OFF at a process value of100C and will turn ON at a processvalue of 99.2C.

J INTEGRAL TIMEIntegral time is the period required for astep-type deviation in integral control(e.g., the deviation shown in the followinggraph) to coincide with the control outputin proportional control action. The shorterthe integral time is, the stronger the inte-gral control action is. If the integral timeis too short, however, hunting may result.

Deviation

Controloutput

PI action (with a short integral time)

PI action(with a long integral time)

P action

(with a short integral time)

(with a long integral time)

T1: Integraltime

J OFFSETProportional control action causes anerror in the process value due to the heatcapacity of the controlled object and thecapacity of the heater, which results in asmall discrepancy between the processvalue and set point in stable operation.This error is called offset. Offset is thedifference in temperature between theset point and the actual processtemperature. Offset may exist above orbelow the set point.

Offset Proportional band

OffsetSetpoint

J SELF-TUNING FUNCTION(Applicable Model: E5jS)

The self-tuning function is incorporatedby E5jS Digital Temperature Controller.The function makes it possible to calcu-late and use an optimum proportionalband automatically according to changein the temperature.

Setpoint

Time

In self-tuningoperation


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J TUNING PID PARAMETERSAll PID process/temperature controllersrequire the adjustment of the P, I, D andother parameters in order to allowaccurate control of the load. If thecontroller is not tuned, then it cannotcontrol the temperature or processvariable of that load with any accuracy.There have been a variety of conven-tional methods suggested and imple-mented to obtain PID constants: Thestep response, marginal sensitivity, andlimit cycle methods. In general, the P, Iand D parameters are tuned eithermanually or via an auto-tuning technique.Auto-tuning methods make it possible toobtain PID constants suitable to a varietyof objects.

Manual Tuning

Step Response Method

The value most frequently used must bethe set point in this method. Calculate themaximum temperature ramp R and thedead time L from a 100% step-type con-trol output. Then obtain the PIDconstants from R and L.

Setpoint

Time

Marginal Sensitivity Method

Proportional control action starts from thestart point A in this method. Narrow thewidth of the proportional band until thetemperature starts to oscillate. Then ob-tain the PID constants from the value ofthe proportional band and the oscillationcycle T at that time.

Setpoint

Time

Marginal sensitivitymethod

Limit Cycle Method

ON/OFF control action starts from thestart point A in this method. Then obtainthe PID constants from the hunting cycleT and oscillation D.

Setpoint

Time

Oscillation

Hunting cycle

Auto-Tuning

Readjustment of PID Constants

PID constants calculated in auto-tuningoperation normally do not cause prob-lems except for some particular applica-tions, in which case, refer to the followingto readjust the PID constants.

Response to Change in ProportionalBand

Wider

Setpoint

It is possible to suppress overshootingalthough a comparatively long startuptime and set time will be required.

Narrower

Setpoint

The process value reaches the set pointwithin a comparatively short time andkeeps the temperature stable althoughovershooting and hunting will result untilthe temperature becomes stable.

Response to Change in Integral Time

Wider

Setpoint

It is possible to reduce hunting, over-shooting, and undershooting although acomparatively long startup time and settime will be required.

Narrower

Setpoint

The process temperature reaches the setpoint within a comparatively short timealthough overshooting, undershooting,and hunting will result.

Response to Change in DerivativeTime

Wider

Setpoint

The process value reaches the set pointwithin a comparatively short time withcomparatively small amounts of over-shooting and undershooting althoughfine-cycle hunting will result due to thechange in process value.

Narrower

Setpoint

It will take a comparatively long time forthe process value to reach the set pointwith heavy overshooting andundershooting.

PID Control and Tuning Methods

Model Type of PID control Auto-tuning methods

PID Advanced PID PID with fuzzy control Step response Limit cycle

E5jJ ---- Fuzzy self-tuning ---- Built-in Built-in

E5jK ---- Auto-tuning, Fuzzy self-tuning ---- Built-in Built-in

E5jN ---- Auto-tuning, Fuzzy self-tuning ---- Built-in Built-in

E5jS Self-tuning ---- ----

E5ZE ---- ---- Auto-tuning (both PID andfuzzy parameters)

Not built-in Built-in


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Alarm

J ALARM OPERATIONThe Temperature Controller comparesthe process value and the preset alarmvalue, turns the alarm signal ON, anddisplays the type of alarm in the presetoperation mode.

Absolute-value AlarmThe absolute-value alarm turns ON ac-cording to the alarm temperature regard-less of the set point in the TemperatureController.

Setting example

Alarm temperature is set to 110C.

Alarm set point

Set point (SV):100C

Alarm value:110C

The alarm set point in the above exampleis set to 110C.

Deviation AlarmThe deviation alarm turns ON accordingto the deviation from the set point in theTemperature Controller.

Setting Example

Alarm temperature is set to 110C.

Alarm setpoint: 10 C

Set point (SV):100C

Alarm value:110C

The alarm set point in the above exampleis set to 10C.

J HEATER BURNOUT ALARM(Single-phase use only)

Many types of heaters are used to raisethe temperature of the controlled object.The CT (Current Transformer) is used bythe Temperature Controller to detect theheater current. If the heaters powerconsumption drops, the TemperatureController will detect the heater burnoutfrom the CT and will output the heaterburnout alarm.

Heater burnout alarm

Currentvalue

Heater burnout

Heater current waveform(CT waveform)

CurrentTrans-former(CT)

The wires connected to theTemperature Controller has no polarity.

Heater

Control outpu

Switch

J LOOP BURNOUT ALARM (LBA)Applicable Models: E5jK

The LBA (loop burnout alarm) is a functionto turn the alarm signal ON by assuming

the occurrence of control loop failure ifthere is no input change with the controloutput set to the highest or lowest value.

Therefore, this function can be used to de-tect control loop errors.

J STANDBY SEQUENCE ALARMIt may be difficult to keep the processvalue outside the specified alarm rangein some cases (e.g., when starting up theTemperature Controller) and as a resultthe alarm turns ON abruptly. This can beprevented with the standby sequentialfunction of the Temperature Controller.This function makes it possible to ignorethe process value right after the Temper-ature Controller is turned on or right afterthe Temperature Controller starts tem-perature control. In this case, the alarmwill turn ON if the process value entersthe alarm range after the process valuehas been once stabilized.

Example of Alarm Output with Stand-by Sequence Set

Temperature Rise

Upper-limitalarm set

Set point

Lower-limitalarm set

Alarmoutput

Temperature Drop

Upper limitalarm set

Set point

Lower limitalarm set

Alarmoutput


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J ALARM SELECTIONS AVAILABLE BY CONTROLLER SERIES

Alarm type Alarm output operation Process/Temperature Controller seriesyp

When X is positive When X is negative K3TL,K3NH

E5CS-X

E5AN,E5EN,E5CN,E5GN

E5AK,E5EK,E5CK

E5jK-T,E5EK-DRT

E5AJ,E5EJ,E5CJ

E5ZE

Upper- andlower-limit(deviation)

*2X X X X X X

Upper-limit(deviation)

X X X X X X X

Lower-limit(deviation)

X X X X X X X

Upper- andlower-limit range(deviation)

*3X X X X X X

Upper- andlower-limit withstandbysequence(deviation)

*5 *4

X X X X X

Upper-limit withstandbysequence(deviation)

X X X X X

Lower-limit withstandbysequence(deviation)

X X X X X

Absolute-valueupper-limit

X X X X X X

Absolute-valuelower-limit

X X X X X

Absolute-valueupper-limit withstandbysequence

X X X

Absolute-valuelower-limit withstandbysequence

X X X

Heater burnoutdetection alarm(uses a currenttransformer input)

E5AKandE5EKonly

E5AK-T andE5EK-T only

X X


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Temperature Sensor

J COLD JUNCTION EFFECTThermocouples only give an accuratereading if the cold end of the device,which is connected to the terminals on acontroller, is maintained at 0C. Sincethis is not practical in industrial applica-tions, controllers are calibrated at areference temperature, usually 20C to25C, and an allowance made for thecold junction error. A sensor (usually asemiconductor) built into the controller,then monitors any changes in this coldjunction, and the controller automaticallycompensates for these changes (this iscalled cold junction compensation). Forthis reason, thermocouple leads shouldalways be connected directly to the

controller terminals. If the leads are tooshort, they may be lengthened by theuse of special compensating cable orthermocouple extension wire thatmatches the thermocouple type.

Sensingpoint350C

Terminal


Cold junctioncompensating circuit

The thermo-electromotive force VT iscalculated from the following formula:VT = K (350 -- 20)

Condition:The terminal temperature is 20C.VT = K (350 -- 20) + K S 20 = K S 350

Thermo-electromotive forceof thermocouple

Thermo-electromotive forcegenerated by cold junctioncompensating circuit

J COMPENSATING CONDUCTORAn actual application may have asensing point located far away from theTemperature Controller. Special-conductor thermocouples are expensive.Therefore, the compensating conductoris connected to the thermocouple in sucha case. The compensating conductormust be in conformity with thecharacteristics of the thermocouple,otherwise precise temperature sensingwill not be possible.

Connectionterminal

Compensatingconductor

Terminal

Temperature

Controller

Example of Compensating ConductorUse

K (350 -- 30) + K (30 -- 20) +K S 20 + K S 350

Thermo-electromotiveforce of thermocouple

Thermo-electromotive forcegenerated by cold junctioncompensating circuit

Thermo-electromotive force throughcompensating conductor

J HOT JUNCTION AND COLD JUNCTIONA thermocouple has a hot junction andcold junction. The hot junction is for tem-perature sensing and the cold junction isconnected to the Temperature Controller.

Hotjunction

Metal A

Metal B

Cold(referencejunction(0C)

J INPUT COMPENSATIONA preset point is added to or subtractedfrom the temperature detected by thetemperature sensor of the TemperatureController to display the process value.The difference between the detectedtemperature and displayed temperatureis set as an input compensation value.

Furnace

Input compensation value: 10C(Displayed value is 120C)(120 -- 110 = 10)


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J PLATINUM RESISTANCE THERMOMETER (RTD)The resistance of a metal will increase asthe temperature of the metal increases.Platinum is especially responsive totemperature changes. RTDs are usuallymade of fine platinum wire wrappedaround a mica or ceramic plate, thenencased in a stainless steel tube.

Three-wire Resistance Thermometer

Omrons temperature/process controllersaccept three-wire platinum resistancethermometer sensors. One of the con-ductors is connected to two wires andthe other resistance conductor is con-nected to another wire, the wiring ofwhich eliminates the influence of resis-tance from the extended lead wires.

Connection of Three-wire PlatinumResistance Thermometer

Platinum resistance thermometer


J SET POINT (SP) RAMPThe SP ramp function controls the targetvalue change rate with the variationfactor. Therefore, when the SP rampfunction is enabled, some range of thetarget value will be controlled if thechange rate exceeds the variation factoras shown at right.

Targetvalueafterchanging

Targetvaluebeforechanging

SP ramp

SP rampset value

SP ramptime unit

Changepoint

Time

J THERMISTORSThese are temperature sensitive semi-conductors, usually encased in a glassbead. For industrial applications, thiswould be housed in a stainless steel tubein common with the other forms of sen-sors described here.

Their main advantage lies in the largechange of resistance with temperaturecompared with other forms of RTD, andof course there is no cold junction effect.

The main disadvantage of thermistors isthat the characteristic is particularly non-

linear, making them a reasonable choiceonly where they are required for controlover a very limited temperature band; forexample, the control of photographicchemical solution temperatures.

J THERMOCOUPLEA thermocouple consists of two differentmetal wires with the ends connectedtogether. When this assembly is heated,a very small voltage, which isproportional to the temperature, appears

at the unheated ends of the wires, and isthe signal used by the controller todetermine the actual temperature. Themost commonly used thermocouples are

Iron/Constantan construction (known asType J) and Nickel-chromium/Nickel-aluminum construction (known asType K).


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Output

J HEATING AND COOLING CONTROLTwo control outputs (one for heating andone for cooling) can be provided by atemperature controller. The relation be-tween these two control outputs is ex-pressed by the V-shaped portion of thediagram. As shown, the two outputs maybe overlapped, or there may be a deadband between the two.

TemperatureController inheating andcoolingcontrol

Heating

CoolingControlledobject

Heating and Cooling Outputs

Heatingoutput

Coolingoutput

Set point

Heatingoutput

Coolingoutput

Set point

J NORMAL OPERATIONThe Temperature Controller in normaloperation will increase control output ifthe process value is higher than the setpoint (i.e., if the Temperature Controllerhas a positive deviation).

Low HighSet point

Controloutput(%

)

J POSITION-PROPORTIONING CONTROLThis control is also called ON/OFF servocontrol. In this control system, the tem-perature and the degree of opening(position) of the control valve are fedback to the temperature controller.

J REVERSE OPERATIONThe Temperature Controller in reverseoperation will increase control output ifthe process value is lower than the setpoint (i.e., if the Temperature Controllerhas a negative deviation).

Low HighSet point

Controloutput(%

)

Temperature Controller inposition-proportioning control.

Open

Close

Controlledobject

Potentiometerreading valveopening.

J TRANSMISSION OUTPUTA Temperature Controller with currentoutput independent from control output isavailable. The process value or set pointwithin the available temperature range ofthe Temperature Controller is convertedinto 4- to 20-mA linear output that can beinput into recorders to keep the results oftemperature control on record. If theTemperature Controller is the E5AX-AFthat has a set limit value, the output willturn ON within the set limit value. Theupper and lower limits can be set fortransmission output in the E5CK-jF.Therefore, the transmission output be-

tween the upper and lower limits will beturned ON if the E5CK-jF is used.

TemperatureController withtransmissionoutput

Recorder

Temperature sensor

Transmissionoutput

Lower limit Upper limit

Process value

Possible setting range


E--17

Setting

J MULTIPLE SET POINTSTwo or more set points independent fromeach other can be set in the TemperatureController in control operation.

J SET LIMITThe set point range depends on the tem-perature sensor and the set limit is used torestrict the set point range. This restrictionaffects the transmission output of the Tem-perature Controller.

Possible setting range

J SETTING MEMORY BANKSThe Temperature Controller stores amaxi-mumof eight groupsof data (e.g., set valueand PID constant data) in built-in memorybanks for temperature control. The Tem-perature Controller selects one of thesebanks in actual control operation.

Memory Bank 0

Bank 1

Bank 7

Set valueP constantI constantD constant:::

Bank 1 is selected.

Temperaturecontrol withdata in memorybank 1.

J SHIFT SET OPERATIONThe set point can be shifted to a differentvalue to be used by the Temperature Con-troller in shift set operation.

Set temperature: 200CShift set point: --50C

Set point:--150C

Shift set operation


E--18

DeviceNett Overview

J WHAT IS THE DEVICENET?DeviceNet is a low-cost communicationslink to connect industrial devices to a net-work and eliminate expensive hardwiring.Typical devices include limit switches,photoelectric sensors, valve manifolds,motor starters, process sensors, barcode readers, variable frequency drives,panel displays and operator interfaces.

The direct connectivity provides im-proved communication between devicesas well as important device-level diag-nostics not easily accessible or availablethrough hardwired I/O interfaces.

DeviceNet is a simple, networkingsolution that reduces the cost and time towire and install industrial automationdevices, while providing interchangeabil-ity of like components from multiplevendors.

J DEVICENET FEATURES AND FUNCTIONALITY

Network size Up to 64 nodes

Network length Selectable end-to-end network distance varies with speedg

Baud rate Distance

125 Kbps 500 m (1,640 ft)

250 Kbps 250 m (820 ft)

500 Kbps 100 m (328 ft)

Data packets 0 to 8 bytes

Bus topology Linear (trunk line/drop line); power and signal on the same networkcable

Bus addressing Peer-to-peer with multi-cast (one-to-many);Multi-master and Master/Slave special case;polled or change-of-state (exception-based)

System features Removal and replacement of devices from the network under power.

J DEVICENET PHYSICAL LAYER AND MEDIAChapter 9, Volume 1 in the DeviceNetSpecifications defines the allowable to-pologies and components. The variety oftopologies that are possible are shown inthe figure below. The specification alsodeals with system grounding, mixingthick and thin media, termination, andpower distribution.

The basic trunk line-drop line topologyprovides separate twisted pair busses for

both signal and power distribution. Thickor thin cable can be used for either trunklines or drop lines. End-to-end networkdistance varies with data rate and cablesize.

Devices can be powered directly fromthe bus and communicate with each oth-er using the same cable. Nodes can beremoved or inserted from the networkwithout powering-down the network.

Power taps can be added at any point inthe network which makes redundantpower supplies possible. The trunk linecurrent rating is 8 amps. An opto-isolateddesign option allows externally powereddevices (e.g., AS drives starters and so-lenoid valves) to share the same buscable. Other CAN-based networks allowonly a single power supply (if at all) forthe entire network.

Short dropsZero drop

Drop line

TapTerminator Terminator

Node Node

Node

Node

Node

Node

Node

Node

Node

Node

Node

Node Node


E--19

Control Period and Manipulated VariableAll time proportional controls have a control period or a similarly named parameter. The parameter, regardless of its name, behaves thesame way in each control

A control period (CP) is the maximum amount of time that the output is on. The CP is defined by the controllers algorithm. Long CPswork better for slower processes, e.g., a temperature change of one degree or less per minute. Shorter CPs work better for faster rates of

change such as several degrees per second.

The Manipulated Variable (MV) also control the output within the limits of the CP. The MV is sometimes referred to by other names bysome manufacturers. These names include control output, percentage output, and manipulated output. The MV is the percentage of out-put power that the algorithm uses to control the output. For example, if the algorithm specifies a CP of 20 seconds and an MV of 50%, the

output will be on for a total of 10 seconds (see illustration below). Note that the output would not be ON for 10 consecutive seconds.

CP = 20 (Omron default) MV = 50%

What would happen in an ideal situation is that the output would trigger ON and OFF throughout the entire 20 seconds, so that at the endof the 20 seconds, the TOTAL TIME ON would be 10 seconds.

Changing the MV would change the TOTAL TIME ON. For example, with the same CP of 20 and an MV of 75%, the TOTAL TIME ONwould be 15 seconds. As in the previous example, the output would not be on for 15 consecutive seconds.

A 5-second control period allows the MV to have the shortest possible ON time. One percent of 5 seconds is 0.05 seconds or 50 ms.

Therefore, 50 ms is the minimum ON time.

Different types of processes require different CPs. If you are controlling a slow-moving process, a long CP allows time for the process toreact to the controllers output signal. However, for a faster moving process, if the output stays on too long, the process variable (e.g.

temperature) exceeds the set point. The controller would then try to readjust itself by shutting off the output, but because the CP is toolarge, the output stays off too long and the PV undershoots the set point. The only way to correct this type of hunting is to shorten the CPof the controller.


E--20

Manual Tuning of PID Values

When PID values should be adjusted manually, refer to the following:

J PID (P) CONTROL ACTION

Offset occurs when the proportional band is large, but the possibility of

overshooting is less likely. On the contrary, when the proportional band issmall, overshooting occurs and the control waveform becomes an ON/OFFcontrol (the occurrence of hunting).

Tuning adjustment:

D Generally, the proportional band should be adjusted from a larger tosmaller value.

D When there is gentle hunting, the hunting can be made smaller bymaking the proportional band wider.

J DERIVATIVE (D) ACTION

Derivative action obtains the original control status as soon as possible bygiving a large quantity of the manipulated variable for rapid external

disturbance. When a longer derivative time is set, the control is disturbed sincethe large quantity of the manipulated variable is continuously working. (Usuallyhunting occurs in shorter periods than the hunting caused by inappropriate

proportional band and integral time.)

Tuning adjustment:

D Generally, derivative time should be adjusted from a shorter to longer time.

D When hunting occurs in a short period, early response of the controlsystem and too strong derivative action are suspected. Shorten the

derivative time.

J INTEGRAL (I) ACTION

Integral action is performed to diminish the offset caused by proportional control

in proportion to the elapsed time. When too short of an integral time is set to

eliminate offset, integral action becomes stronger and it may cause hunting.

Tuning adjustment:

D Generally, integral time should be adjusted from a longer to shorter time.

D When there is gentle hunting or repetition of overshooting, too strong of anintegral action is suspected in many cases. Hunting can become smaller ifa longer time is set. (It is also possible to make integral action weaker by

making the proportional band wider.)


E--21

GlossaryAdaptive TuningUsed to continuously monitor and

optimize PID constants while the

controller operates. Three tuningalgorithms are used to recalculate thePID constants within 500 ms after the

process value stabilizes at set point:Step-response method, disturbance

tuning and hunting tuning

Anti-reset Wind-up (ARW)A feature of PID controllers that prevents

the integral (auto-reset) circuit fromoperating when the temperature isoutside the proportional band.

Alpha ()This represents the temperature

coefficient of the change in electrical

resistance of a material. For each C intemperature the electrical resistancechanges. It is the defining parameter for

platinum resistance temperaturedetectors (RTD sensors). The unit of

measure is ohms/ohms/C.AnalogData collected and represented bycontinuously variable quantities, such as

voltage measurement or temperaturevariation.

Analog OutputA continuously variable signal that is

used to represent a value, such as theprocess value or set point value. Typical

ranges include 4 to 20 mA, 0 to 20 mA, 1to 5 VDC, and 0 to 5 VDC.

Auto-tuningThis feature automatically calculates

then resets the PID values based ontemperature control performance over a

sampled period. In some of Omronscontrollers, auto-tuning also optimizes

the settings for fuzzy logic control values.

Burnout FunctionAn action to release the output when thethermocouple has burned out, platinum

RTD develops an open or short, orinfrared problems occur.

CEA marking on products that comply with

European Union requirements pertainingto safety and electromagneticcompatibility.

CelsiusA temperature scale in which waterfreezes at 0C and boils at 100C atstandard atmospheric pressure. Theformula to convert Fahrenheittemperatures to Celsius is as follows:F = (1.8 x C) + 32.

Cold Junction CompensationElectronic means of compensating for

the ambient temperature at the cold

junction of a thermocouple so itmaintains a reference to 0C.Contact OutputRelay control outputs are often availablein these contact forms:

Form A Contact (SPST-NO)

Single-pole, single-throw relays use thenormally open and common contacts toswitch power. The contacts close when

the relay coil is energized and openwhen power is removed from the coil.

Form B Contact (SPST-NC)Single-pole, single-throw relays use the

normally closed and common contacts.These contacts open when the relay coil

is energized and close when power is

removed from the coil.

Form C Contact (SPDT)Single-pole, double-throw relays use the

normally open, normally closed andcommon contacts. The relay can bewired as a Form A or Form B contact.

Control ActionThe control output response relative tothe difference between the process

variable and the set point. For reverseaction (usually heating), as the processdecreases below the set point, the outputincreases. For direct action (usually

cooling), as the process increases abovethe set point, the output increases.

Control ModeThe type of control action used by the

controller can include ON/OFF,time-proportioning, PD, and PID. Other

combinations and refinements are used.

CSACanadian Standards Association is anindependent testing laboratory that

establishes commercial and industrialstandards, as well as tests products and

certifies them.

C-ULThis symbol appearing in literature andmarked on products indicates Canadian

recognition of Underwriters Laboratories,Inc. approval of particular product

classes. The C-UL approval may stand inplace of Canadian Standards Association

certification. All references to C-UL arebased on prior listing or recognition fromthe original UL file.

Dead BandThe time period in a control systembetween a change in stimuli and any

measurable response in the controlledvariable. In the deadband, specific

conditions can be placed on control

output actions. Operators select the dead

band width. It is usually above theheating proportional band and below the

cooling proportional band.

DerivativeThe rate of change in a process variablewhich forms the D in a PID control

algorithm. This control action anticipatesthe rate of change of the process and

compensates to minimize overshoot andundershoot. Derivative control is an

instantaneous change of the controloutput in the same direction as theproportional error. This is caused by a

change in the process variable (PV) thatdecreases over the derivative time.

DeviationA departure of a controlled variable froma command such as set point.

Deviation indicationA system of indication in which adeparture of a detected value from theset point is indicated.

DIN (Deutsche Industrial Norm)A German standards agency that sets

world-recognized engineering andindustrial standards.

DIN 43760The standard that defines the

characteristics of a 100-ohm platinumRTD having a resistance vs. temperature

curve specified by a = 0.00385 ohms perdegree.

DriftA gradual change over a long period oftime that affects the reading or value.Changes in ambient temperature,

component aging, contamination,humidity and line voltage all contribute to

drift.

DroopControllers using only proportionalcontrol can settle at a value below the

actual set point once the systemstabilizes. This offset is corrected with

the addition of Integral control in thecontrol algorithm.

Electromagnetic CompatibilityTo conform with CEs EMC requirements,

equipment or a system must operatewithout introducing significant

electromagnetic disturbances to theenvironment or be affected byelectromagnetic disturbances.

Electromagnetic InterferenceThere are many possible sources forelectromagnetic interference (EMI) in an

industrial control setting. It can originateas electrical or magnetic noise caused byswitching AC power on inside the sine


E--22

wave. EMI interferes with the operation

of controls and other devices. The EMCsection in Specifications shows acontrollers resistance to EMI.

Electromechanical RelayA power switching device that completesor interrupts a circuit by physically

moving electrical contacts into contactwith each other. These are used primarilyfor ON/OFF control operation.

EventA programmable ON/OFF output signal.Events can control peripheral equipment

or processes, or act as an input foranother control loop. Event input boardsare an option for most Omron controllers.

FahrenheitA temperature scale that has 32 at theice point and 212 at the boiling point ofwater at sea level. To convert Fahrenheitto Celsius, subtract 32 from F andmultiply the remainder by 0.556.

Full IndicationA system of indication in which adetected value is indicated with a setting

range.

Fuzzy LogicA rule-based control algorithm thatenables control devices to make

subjective judgments in a way similar tohuman decision-making. Within a

process controller, fuzzy logic uses somebasic information about the system,which is input by the user, to emulate the

way an expert operator who wasmanually controlling the system would

react to a process upset.

Heat SinkAn object that conducts and dissipates

heat away from an object in contact withit. Solid state relays usually use a finnedaluminum heat sink to dissipate heat.

Hot Junction and Cold JunctionIf a thermocouple is generating a voltage,this means that there is a temperature

difference between the two ends of thethermocouple. The hot end is the onethat makes contact with the temperature

process being controlled. The cold end isat the sensor input terminals.

HuntingOscillation of the process temperaturebetween the set point and the processvariable. Derivative control is used in the

control algorithm to reduce hunting.

Hysteresis (Dead Band)A temperature band between the ON and

OFF of an output in the ON/OFF controlaction. No heating or cooling takes place.The band occurs between the ON and

OFF points.

InfraredThe portion of the electromagnetic

spectrum with wavelengths ranging fromone to 1000 microns. These wavelengths

are ideal for radiant heating andnon-contact temperature sensing.

Input Digital FilterA device used to sample the input slower

than the scan rate to allow the controllerto monitor an input that changes very

rapidly and still have sufficientinformation from the process to control it.

Input ScalingThe ability to scale input readings (% of

full scale) to the engineering units of theprocess variable.

Input TypeThe type of device used to provide a

signal of temperature change. Theseinclude thermocouples, RTDs, linear or

process current or voltage inputs.

Integral Action (I)Control action that eliminates offset, ordroop, between set point and actual

process temperature. This is the I in the

PID control algorithm.

Joint Industrial Standards (JIS)A Japanese agency that establishes and

maintains standards for equipment andcomponents. Its function is similar to

Germanys Deutsche Industrial Norm.

LinearityA measure of the deviation of aninstruments response from a straight

line.

Loop Break AlarmThis alarm indicates a problem in the

control loop, e.g., a sensor has becomedisconnected or a problem has

developed with the final control element.

Manipulated VariableThe final output percentage (0 to 100%)that will be sent to a control element.

This percentage can be related to avalve position, a 4-20 mA signal, or the

amount of ON time from a pulsed controloutput.

Manipulated Variable ForcingThe manipulated variable can be forced

to a specified user-programmed valueunder the following circumstances:

1. A sensor break occurs

2. An error in the process occurs

3. Stop mode is activated

Manipulated Variable LimitingA control option used when the processcannot handle the full output of the

heater or final control device. To limit the

manipulated variable, the user programsthe controller so that it never sends a

100% output to the final control element.

Manual ModeA selectable mode that has no automatic

control aspects. The user sets the outputlevels.

Multiple Set PointsTwo or more set points independent fromeach other which can be set in thetemperature controller.

National Electrical ManufacturersAssociation (NEMA)The United States organization thatestablishes specifications and ratings for

electrical components and apparatus.Conformance by manufacturers is

voluntary. However, UnderwritersLaboratories will test products to NEMAratings for operating performance and

enclosure ratings.

National Institute of Standardsand Technology (NIST)Formerly the National Bureau ofStandards, this United States agency isresponsible for establishing scientific and

technical standards.

NEMA 4XThis enclosure rating specification

certifies that a controllers front panelresists water washdown and is corrosionresistant in indoor usage.

Normal ActionA control action which will increase thecontrol output if the process value is

higher than the set point. This action issuitable for a cooling system.

OffsetA controlled deviation (the difference in

temperature between the set point andthe actual process temperature)

remaining after a controlled systemreaches its steady state. The offset(droop) is created by the correlation

between the thermal capacity of thecontrolled system and the capacity of

heating equipment.

ON/OFF Control ActionA control action which turns the outputfully on until the set point is reached, and

then turns off. Also called two-positioncontrol action.

OvershootThe number of degrees by which aprocess exceeds the set pointtemperature.

Process VariableThe parameter that is controlled ormeasured, such as temperature, relative

humidity, flow and pressure.

Proportional BandThe range of temperature in which amanipulated variable is proportionate toany deviation from the set point.


E--23

Proportional Control Action (P)A control action in which the manipulated

variable is proportionate to any deviationfrom the set point.

Proportional PeriodA cycle of ON and OFF operations of theoutput relay in a time-divisionproportional control action.

Proportioning Control PlusDerivative Function (PD)A time-proportioning controller that has aderivative function. The derivative

function monitors the rate at which asystems temperature is either increasing

or decreasing and adjusts the cycle timeof the controller to minimize overshoot orundershoot.

Proportioning Control withIntegral and Derivative Functions(PID)A time-proportioning controller that has

integral and derivative functions. The

integral function automatically raises thestabilized system temperature to matchthe set point temperature to eliminate the

difference caused by thetime-proportioning function. The

derivative function monitors the rate ofrise or fall of the system temperature andautomatically adjusts the cycle time of

the controller to minimize overshoot andundershoot. Also called three-mode

control.

RangeThe difference between the lower andupper limits of a measurement quantity.

Rate Action (D)The controller senses the rate of changeof temperature and provides an

immediate change of output to minimizethe eventual deviation.

Remote Set PointA remote set point allows a controller toreceive its set point from a source otherthan itself.

Reset (Auto Reset) ActionThere is a manual adjustment that can

be applied to the offset by changing theset value dial or moving the offset screwon the control panel. The auto-resetfunction automatically adjusts the set

value to eliminate offset.

Resistance Temperature Detector(RTD)A coil of wire, usually platinum, whose

resistance increases linearly with a risein temperature. RTDs generally have a

higher accuracy rating thanthermocouples.

Reverse ActionA control action in which the output

power will be inversely proportional tothe deviation. An increase in the process

variable will cause a decrease in theoutput power, making this action suitablefor a heating system.

Serial CommunicationsA method of transmitting informationbetween devices by sending all bits

serially over a communication channel.RS-232 is used for point-to-pointconnections of a single device, usually

over a short distance.RS-422/RS-485 communicates with

multiple devices on a single, common

cable over longer distances.

Set PointThe value set on the process or

temperature controller to control thesystem.

Soft StartA method of applying power graduallyover a period of seconds to controlleddevices such as heaters, pumps and

motors. This lengthens the service life ofthe load by limiting in-rush current to

inductive loads.

Solid State Relay (SSR)A switching device with no moving parts

that completes or interrupts a circuitelectrically.

Thermal ResponseThe time required for the response curve

of the temperature sensor to rise to aspecified percentage level (usually either

63% or 90%).

Thermistor SensorA small bead of semiconducting materialat the tip detects temperature. The

resistance of the bead decreasessignificantly with a rise in temperature for

a highly sensitive input device.

Thermocouple SensorA device the converts heat to electricity.Usually made of two wires, each of a

different metal or alloy. The wires arejoined at one end, known as the hot

end. The hot end makes thermal contactwith the process to be controlled. Thecold end terminals are connected to the

sensor input. Voltages are created atboth the hot and cold ends. The

controller measures the cold endtemperature to determine the hot endtemperature.

Underwriters Laboratories (UL)This independent testing laboratories

establishes commercial and industrialstandards, as well as tests and certifies

products in the US. They also offertesting to Canadian StandardsAssociation requirements with products

bearing the cUL marking.

UndershootThis is the amount by which the process

variable falls below the set point before itstabilizes.

Zero Cross SwitchingUsed in solid state relays, this action

provides output switching only at or nearthe zero-voltage crossing point of the AC

sine wave. It reduces electromagneticinterference and high inrush currentsduring initial turn-on.


E--24

Enclosure Ratings

J NEMA RATINGS AT A GLANCE FOR NON-HAZARDOUS LOCATIONS

Protection against thesei t l diti

Type of enclosuregenvironmental conditions

1 2 3 3R 3S 4 4X 5 6 6P 11 12 12K 13

Accidental contact with the enclosedequipment

X X X X X X X X X X X X X X

Falling dirt X X ---- ---- ---- X X X X X X X X X

Falling liquids, light splashing ---- X ---- ---- ---- X X ---- X X X X X X

Dust, lint, fibers and flyings(non-combustible, non-ignitable)

---- ---- ---- ---- ---- X X X X X ---- X X X

Windblown dust ---- ---- X ---- X X X ---- X X ---- ---- ---- ----

Hosedown and splashing water ---- ---- ---- ---- ---- X X ---- X X ---- ---- ---- ----

Oil and coolant seepage ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- X X X

Oil or coolant spraying and splashing ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- X

Corrosive agents ---- ---- ---- ---- ---- ---- X ---- ---- X X ---- ---- ----

Occasional temporary submersion ---- ---- ---- ---- ---- ---- ---- ---- X X ---- ---- ---- ----

Occasional prolonged submersion ---- ---- ---- ---- ---- ---- ---- ---- ---- X ---- ---- ---- ----

J IEC (INTERNATIONAL ELECTROTECHNICAL COMMISSION) RATINGSThe IEC defines degrees of protection

provided by electrical enclosures withrespect to personnel, equipment withinthe enclosure and ingress of water. The

degree of protection is expressed by theletters IP followed by two numerals

(Example: IP67). See the table at rightfor an explanation of the numerals. Thefollowing information is drawn from IEC

publication 144 of 1963 and 529 of 1976.

By contrast to NEMA, IP ratings do not

apply to protection against the risk ofexplosion or conditions such as humidity,corrosive gases, fungi or vermin. Also,

different parts of a piece of equipmentcan have different degrees of protection

and still comply with the standards. Anexample would be the opening in thebase of an enclosure.

1st characteristic numeral 2nd characteristic numeral

Protection against contact and penetration of solid bodies Protection against the penetration of lqiuids.

0 Not protected 0 Not protected.

1 Protection against solid objects greater than 50 mm. 1 Protection against dripping water.

2 Protection against solid objects greater than 12 mm. 2 Protection against dripping water when tilted up to 15.3 Protection against solid objects greater than 2.5 mm. 3 Protection against rain.

4 Protection against solid objects greater than 1 mm. 4 Protection against splashing water.

5 Dust protected. 5 Protection against water jets.

6 Dust tight. 6 Protection against heavy seas.

---- ---- 7 Protection against the effects of immersion

---- ---- 8 Protection against immersion.


E--25

J THERMOELECTRIC VOLTAGE FOR THERMOCOUPLE SENSORS (in mV)

Type K ThermocouplesMeet NBS 561, DIN 43710 1977, BS 4937 1973, JIS-C 1602-1981

Temperature C 0 10 20 30 40 50 60 70 80 900 0.000 0.397 0.798 1.203 1.611 2.022 2.436 2.850 3.266 3.681

100 4.095 4.508 4.919 5.327 5.733 6.137 6.539 6.939 7.338 7.737

200 8.137 8.537 8.938 9.341 9.745 10.151 10.560 10.969 11.381 11.793

300 12.207 12.623 13.039 13.456 13.874 14.292 14.712 15.132 15.552 15.974

400 16.395 16.818 17.241 17.664 18.088 18.513 18.938 19.363 19.788 20.214

500 20.640 21.066 21.493 21.919 22.346 22.772 23.198 23.624 24.050 24.476

600 24.902 25.327 25.751 26.176 26.599 27.022 27.445 27.867 28.288 28.709

700 29.128 29.547 29.965 30.383 30.799 31.214 31.629 32.042 32.455 32.866

800 33.277 33.686 34.095 34.502 34.909 35.314 35.718 36.121 36.524 36.925

900 37.325 37.724 38.122 38.519 38.915 39.310 39.703 40.096 40.488 40.879

1000 41.269 41.657 42.045 42.432 42.817 43.202 43.585 43.968 44.349 44.729

1100 45.108 45.486 45.863 46.238 46.612 46.985 47.356 47.726 48.095 48.462

1200 48.828 49.192 49.555 49.916 50.276 50.633 50.990 51.344 51.697 52.049

1300 52.398 52.747 53.093 53.439 53.782 54.125 54.466 54.807

Type J ThermocouplesMeet NBS 561, BS 4937 1973, JIS-C 1602-1981

Temperature C 0 10 20 30 40 50 60 70 80 900 0.000 0.507 1.019 1.536 2.058 2.585 3.115 3.649 4.186 4.725

100 5.268 5.812 6.359 6.907 7.457 8.008 8.560 9.113 9.667 10.222

200 10.777 11.332 11.887 12.442 12.998 13.553 14.108 14.663 15.217 15.771

300 16.325 16.879 17.432 17.984 18.537 19.089 19.640 20.192 20.743 21.295

400 21.846 22.397 22.949 23.501 24.054 24.607 25.161 25.716 26.272 26.829

500 27.388 27.949 28.511 29.075 29.642 30.210 30.782 31.356 31.933 32.513

600 33.096 33.683 34.273 34.867 35.464 36.066 36.671 37.280 37.893 38.510

700 39.130 39.754 40.382 41.013 41.647 42.283 42.922 43.563 44.207 44.852

800 45.498 46.144 46.790 47.434 48.096 48.716 49.354 49.989 50.621 51.249

900 51.875 52.496 53.115 53.729 54.341 54.948 55.553 56.155 56.753 57.349

1000 57.942 58.533 59.121 59.708 60.293 60.876 61.459 62.039 62.619 63.199

1100 63.777 64.355 64.933 65.510 66.087 66.664 67.240 67.815 68.390 68.964

1200 69.536

Type J-DIN Thermocouples (Fe-CuNi)Meet DIN 43710 1977

Temperature C 0 10 20 30 40 50 60 70 80 900 0.000 0.520 1.050 1.580 2.110 2.650 3.190 3.730 4.270 4.820

100 5.370 5.920 6.470 7.030 7.590 8.150 8.710 9.270 9.830 10.222

200 10.950 11.510 12.070 12.630 13.190 13.750 14.310 14.880 15.440 16.000

300 16.560 17.120 17.680 18.240 18.800 19.360 19.920 20.480 21.040 21.600

400 22.160 22.720 23.290 23.860 24.430 25.000 25.570 26.140 26.710 27.280

500 27.850 28.430 29.020 29.590 30.170 30.750 31.330 31.910 32.490 33.080

600 33.670 34.260 34.850 35.440 36.040 36.640 37.250 37.850 38.470 39.090

700 39.720 40.350 40.980 41.620 42.270 42.920 43.570 44.230 44.890 45.550

800 46.220 46.890 47.570 48.250 48.940 49.630 50.320 51.020 51.720 52.431

Note: The reference junction for thermocouples is at 0C.


E--26

Type R ThermocouplesMeet NBS 561, BS 4937 1973, JIS-C 1602-1981

Temperature C 0 10 20 30 40 50 60 70 80 900 0.000 0.054 0.111 0.171 0.232 0.296 0.363 0.431 0.501 0.573

100 0.647 0.723 0.800 0.879 0.959 1.041 1.124 1.208 1.294 1.380

200 1.468 1.557 1.647 1.738 1.830 1.923 2.017 2.111 2.207 2.302

300 2.400 2.498 2.596 2.695 2.795 2.896 2.997 3.099 3.201 3.304

400 3.407 3.511 3.616 3.721 3.826 3.933 4.039 4.146 4.254 4.362

500 4.471 4.580 4.689 4.799 4.910 5.021 5.132 5.244 5.356 5.469

600 5.582 5.696 5.810 5.925 6.040 6.155 6.272 6.388 6.505 6.623

700 6.741 6.860 6.979 7.098 7.218 7.339 7.460 7.582 7.703 7.826

800 7.947 8.072 8.196 8.320 8.445 8.570 8.696 8.822 8.949 9.076

900 9.203 9.331 9.460 9.589 9.718 9.848 9.978 10.109 10.240 10.371

1000 10.503 10.636 10.768 10.902 11.035 11.170 11.304 11.439 11.574 11.710

1100 11.846 11.983 12.119 12.257 12.394 12.532 12.669 12.808 12.946 13.085

1200 13.224 13.363 13.502 13.642 13.782 13.922 14.062 14.202 14.343 14.483

1300 14.624 14.765 14.906 15.047 15.188 15.329 15.470 15.611 15.752 15.893

1400 16.035 16.176 16.317 16.458 16.599 16.741 16.882 17.022 17.163 17.304

1500 17.445 17.585 17.726 17.866 18.006 18.146 18.286 18.425 18.564 18.703

1600 18.842 18.981 19.119 19.257 19.395 19.533 19.670 19.807 19.941 20.080

1700 20.215 20.350 20.483 20.616 20.748 20.878 21.006

Type S ThermocouplesMeet NBS 561, DIN 43710 1977, BS 4937 1973, JIS-C 1602-1981

Temperature C 0 10 20 30 40 50 60 70 80 900 0.000 0.055 0.113 0.173 0.235 0.299 0.365 0.432 0.502 0.573

100 0.645 0.719 0.795 0.872 0.950 1.029 1.109 1.190 1.273 1.356

200 1.440 1.525 1.611 1.698 1.785 1.873 1.962 2.051 2.141 2.232

300 2.323 2.414 2.506 2.599 2.692 2.786 2.880 2.974 3.069 3.164

400 3.260 3.356 3.452 3.549 3.645 3.743 3.840 3.938 4.036 4.135

500 4.234 4.333 4.432 4.532 4.632 4.732 4.832 4.933 50.34 5.136

600 5.237 5.339 5.442 5.544 5.648 5.751 5.855 5.960 6.064 6.169

700 6.274 6.380 6.486 6.592 6.699 6.805 6.913 7.020 7.128 7.236

800 7.345 7.454 7.563 7.672 7.782 7.892 8.003 8.114 8.225 8.336

900 8.448 8.560 8.673 8.786 8.899 9.012 9.126 9.240 9.355 9.470

1000 9.585 9.700 9.816 9.932 10.048 10.165 10.282 10.400 10.517 10.635

1100 10.754 10.872 10.991 11.110 11.229 11.348 11.467 11.587 11.707 11.827

1200 11.947 12.067 12.188 12.308 12.429 12.550 12.671 12.792 12.913 13.034

1300 13.155 13.276 13.397 13.519 13.640 13.716 13.883 14.004 14.125 14.247

1400 14.368 14.489 14.610 14.731 14.852 14.973 15.094 15.215 15.336 15.456

1500 15.576 15.697 15.817 15.937 16.057 16.176 16.296 16.415 16.534 16.653

1600 16.771 16.890 17.008 17.125 17.243 17.360 17.477 17.594 17.711 17.826

1700 17.942 18.056 18.170 18.282 18.394 18.504 18.612

Note: The reference junction for thermocouples is at 0C.


E--27

J TEMPERATURE vs. RESISTANCE FOR PLATINUM RTD SENSORS (Ohms)

Sensors Conform to JIS-C 1604 1981 Standard

Temperature C 0 10 20 30 40 50 60 70 80 90--200 17.14 21.46 25.80 30.12 34.42 38.68 42.91 47.11 51.29 55.44

--100 59.57 63.68 67.77 71.85 75.91 79.96 83.99 88.01 92.02 96.02

0 100.00 103.97 107.93 111.88 115.81 119.73 123.64 127.54 131.42 135.30

100 139.16 143.01 146.85 150.67 154.49 158.29 162.08 165.86 169.63 173.38

200 177.13 180.86 184.58 188.29 191.99 195.67 199.35 203.01 206.66 210.30

300 213.93 217.54 221.15 224.74 228.32 231.89 235.45 238.99 242.53 246.05

400 249.56 253.06 256.55 260.02 263.49 266.94 270.38 273.80 277.22 280.63

500 284.02 287.40 290.77 294.12 297.47 300.80 304.12 307.43 310.72 314.01

600 317.28 320.54 323.78 327.02 330.24

Sensors Conform to DIN 43760 1968, BS1964 1904 Standard

Temperature C 0 10 20 30 40 50 60 70 80 90--200 18.53 22.78 27.05 31.28 35.48 39.65 43.80 47.93 52.04 56.13

--100 60.20 64.25 68.28 72.29 76.28 80.25 84.21 88.17 92.13 96.07

0 100.00 103.90 107.79 111.67 115.54 119.40 123.24 127.07 130.89 134.70

100 138.50 142.28 146.06 149.82 153.57 157.32 161.04 164.76 168.47 172.16

200 175.84 179.51 183.17 186.82 190.46 194.08 197.70 201.30 204.88 208.46

300 212.03 215.58 219.13 222.66 226.18 229.69 233.19 236.67 240.15 243.61

400 247.06 250.50 253.93 257.34 260.75 264.14 267.52 270.89 274.25 277.60

500 280.93 284.26 287.57 290.87 294.16 297.43 300.70 303.95 307.20 310.43

600 313.65 316.86 320.05 323.24 326.41 329.57 332.72 335.86 338.99 342.10

700 345.21


E--28

J RESISTANCE RATIO THERMISTOR SENSORS

Temperature Characteristics

Operatingt t

--50 to 50Cp gtemperatureC Ratio Ratio

deviation

--55 3.514

--50 3.415 0.022--40 3.168 0.029--30 2.851 0.034--20 2.497 0.036--10 2.148 0.0330 1.841 0.028

10 1.592 0.02220 1.403 0.01730 1.264 0.01240 1.165 0.00950 1.094 0.006

Operatingt t

0 to 100Cp gtemperatureC Ratio Ratio

deviation

--10 3.689

0 3.415 0.03010 3.096 0.03320 2.755 0.03430 2.419 0.03340 2.110 0.02950 1.841 0.02560 1.617 0.02070 1.436 0.01680 1.293 0.01390 1.181 0.010

100 1.094 0.008110 1.026

Operatingt t


deviation

40 3.774

50 3.415 0.03760 3.051 0.03670 2.700 0.03480 2.377 0.03190 2.089 0.027

100 1.841 0.023110 1.630 0.019120 1.454 0.016130 1.309 0.013140 1.191 0.011150 1.094 0.009160 1.015

Operatingt t


deviation

90 3.627

100 3.415 0.022110 3.186 0.023120 2.953 0.023130 2.722 0.023140 2.499 0.022150 2.290 0.020160 2.096 0.019170 1.921 0.017180 1.764 0.015190 1.626 0.013200 1.504 0.012210 1.398 0.010220 1.305 0.009230 1.225 0.008240 1.155 0.007250 1.094 0.006260 1.041

Operatingt t


deviation

140 3.672

150 3.415 0.026160 3.161 0.025170 2.916 0.024180 2.683 0.023190 2.466 0.021200 2.265 0.019210 2.083 0.018220 1.917 0.016230 1.768 0.014240 1.634 0.013250 1.515 0.011260 1.409 0.010270 1.316 0.009280 1.232 0.008290 1.159 0.007300 1.094 0.006310 1.036

Operatingt t


deviation

190 3.665

200 3.415 0.025210 3.167 0.025220 2.926 0.024230 2.695 0.023240 2.477 0.021250 2.274 0.020260 2.088 0.018270 1.919 0.016280 1.767 0.014290 1.633 0.013300 1.517 0.011310 1.411 0.010320 1.317 0.009330 1.223 0.008340 1.160 0.007350 1.094 0.006360 1.036

Note: Ratio deviation means a deviation in the ratio of resistance from specified temperature per each 1C change in the measuredtemperature.


E--29

J INTERCHANGEABLE THERMISTOR SENSORS

Resistance vs. Temperature CharacteristicsThese values apply to thermistor sensors used with E5C2 temperature controllers.

Range --50 to 100CResistance 6 K at 0C (nominal)Constant B 3390K

Tempera-ture C

Resistance(K)

Deviation(K)

--50 75.360 4.280--40 42.900 2.280--30 25.230 1.260--20 15.210 0.720--10 9.414 0.4220 6.000 0.261

10 3.934 0.15820 2.637 0.10030 1.812 0.06540 1.266 0.04350 0.904 0.02960 0.685 0.02070 0.487 0.01480 0.366 0.01090 0.279 0.007100 0.216 0.005110 0.168

120 0.133

Range 0 to 150CResistance 30 K at 0C (nominal)Constant B 3450K

Tempera-ture C

Resistance(K)

Deviation(K)

--20 77.070

--10 47.410

0 30.000 1.35010 19.490 0.80020 12.970 0.50030 8.828 0.32340 6.140 0.21250 4.356 0.14460 3.147 0.09870 2.317 0.06880 1.734 0.04890 1.318 0.035100 1.017 0.026110 0.794 0.019120 0.628 0.014130 0.502 0.011140 0.405 0.008150 0.330 0.006160 0.272

170 0.226


Tempera-ture C

Resistance(K)

Deviation(K)

30 28.050

40 19.310

50 13.570 0.47060 9.717 0.31070 7.081 0.21480 5.243 0.15190 3.939 0.108

100 3.000 0.080110 2.314 0.058120 1.805 0.043130 1.424 0.033140 1.134 0.025150 0.912 0.019160 0.735 0.015170 0.596 0.012180 0.487 0.010190 0.400 0.008200 0.331 0.006

Range 100 to 250CResistance 550 , 200C (nominal)Constant B 4300K

Tempera-ture C

Resistance(K)

Deviation(K)

80 12.660

90 8.626

100 6.281 0.194110 4.649 0.134120 3.495 0.096130 2.664 0.069140 2.056 0.051150 1.510 0.039160 1.273 0.029170 1.017 0.022180 0.824 0.017190 0.669 0.013200 0.550 0.010210 0.455 0.008220 0.381 0.007230 0.319 0.005240 0.270 0.004250 0.230 0.003260 0.197

270 0.169


Tempera-ture C

Resistance(K)

Deviation(K)

130 23.060

140 17.440

150 13.330 0.350160 10.290 0.260170 8.027 0.194180 6.312 0.147190 5.006 0.113200 4.000 0.087210 3.221 0.068220 2.611 0.053230 2.131 0.042240 1.751 0.034250 1.445 0.027260 1.202 0.022270 1.004 0.018280 0.842 0.014290 0.711 0.012300 0.602 0.010310 0.513

320 0.428


Tempera-ture C

Resistance(K)

Deviation(K)

180 13.390

190 10.290

200 38.000 0.190210 6.305 0.146220 5.015 0.111230 4.014 0.086240 3.240 0.067250 2.634 0.054260 2.156 0.042270 1.779 0.033280 1.474 0.027290 1.228 0.022300 1.030 0.018310 0.868 0.014320 0.738 0.012330 0.631 0.010340 0.542 0.008350 0.468 0.007

Note: Resistance deviation means a deviation of actual resistance at the specified temperature per each 1C change in the measuredtemperature.


E--30

Documents

C14Temp&ProcessRefInfo0604