Hygrostat HG 80with "Polyga®" HG 80-2humidity measuring element HG 80iwith one or two changeover contacts HG 80vswith inner rotary know or set point protection

measuring range 30...100%rh.

Technical Datameasuring range (scale range) ........................ 30...100%rhmeasuring accuracy

for measuring range>50%rh ............. ±3.5%rhfor measuring range<50%rh ............. ±4.0%rh

setting range (range of operation) ................... 35...100%rhmeasuring medium ....... air, pressureless, non-aggressiveswitching difference (microswitch) .......................... ca 3...6%rhswitchingdistance between the microswitches for theHG80-2 .... 0...+15%rhmax. voltage ............................................................... 250 V AC

!!!Caution: 250V only on condition that there is no build-up of condensate in the measuring head - otherwisevoltage arcing may result.

breaking capacity of the changeover contactohmic load (cos ϕ=1) .................................. 15A AC 230Vinductive load (cos ϕ=0,7) ............................. 2A AC 230Vdirect voltage ............................................. 0,25A DC 230Vat low voltage ............................................ 100mA, 125V AC

contact material ................................................................ silverallowable ambient temperature ......................... -30...+60°Callowable working temperature ................................ 0...60°Cmedium temp. coefficient ..... -0,2%/K relative to 20°C and 50%rh

adjustment .................... at average air pressure 430 m NNallowable air speed ...................................................... 8m/sec

with gauze protection (ord no. 20.014) ............ 15m/sectime constant T63 at v=2m/sec ...................................... 120 secsensor length, material ................ 220mm, high-grade steelfixing ............... slots in the housing base for duct mounting

(ord. no. 20.009) ........................... console for wall mountingmounting position .................... sensor vertically downwards

or horizontallyconnecting terminals .... for conductor cross sections 1.5mm2

cable connection ............................... via twist nipple M20x1,5electromagnetic compatibility EMC

resistance to interference ................... ref. EN 50 082-2interference emission ......................... ref. EN 50 081-2

housing ............................................................... ABS light greytype of protection (outer rotary knob) ............................. IP 54type of protection (inner rotary knob HG80i, HG802i).......IP64weight ................................................................................. 0.7 kg"subject to technical modifications"

Description of the HygrostatThe humidity measuring element, produced under thename „Polyga®“, consists of several synthetic fabricbands each with 90 individual fibres with a diameter of0.003mm. A special process gives the fibre hygroscopicproperties. The measuring element absorbs and desorbshumidity. The swelling effect, which is predominantly ina lengthways direction, is carried via a suitable leversystem to a microswitch with an extremely small switchingpath. The measuring element reacts quickly and preciselyto the change in air humidity. By adjusting the set valuecontrol knob, the lever system is engaged so that whenthe set air humidity is reached the microswitch is activated.

In the case of the hygrostat type HG80-2, a secondmicroswitch is positioned parallel to the first microswitch.After the housing cover has been removed, the secondset value can be finely adjusted at the microswitch leverusing a screwdriver. The switch point of the secondmicroswitch is connected to the switch point of the firstmicroswitch. The switch distance (neutral zone) can beset from 0% rel. humidity to +15% rel. humidity.

The fan shaped measuring element is protected by aperforated sensor tube and is exposed to the housing.The hygrostats are designed for pressureless systems.The mounting position should be chosen such thatcondensed water cannot get into the interior of thehousing. The preferred mounting position is with the„sensor vertically downwards“ or „sensor horizontal“(see diagram on the reverse). In the mounting positionsdescribed above, a blanking plate in the sensor tube witha 0.8mm diameter hole will prevent water getting in.

ApplicationThe hygrostat type HG80 is used as an on-off controller tocontrol the relative air humidity in air ducts of air conditioningunits and climatic cabinets, and to control air humidifiersand dehumidifiers. Other areas of use are storage of food-stuffs and luxury foods, cooling rooms for fruit and vegeta-bles, greenhouses for gardening use, the textile industry,the paper and printing industry, film industry and hospitals.

The hygrostat HG80 can be used almost anywhere that airhumidity has to be regulated or monitored.

D-42607 Solingen P.O.Box 10 07 08D-42659 Solingen Ritterstr. 87-89Phone +49 212 81 40 45 Fax +49 212 81 55 00eMail: mail@juchheim-solingen.deInternet: www.juchheim-solingen.de

Connection diagram

Dimensions diagram

Accessories

Console for wall mounting order no. 20.009

gauze protector order no. 20.014

protection tube for exterior mounting withoutventilation fan order no. 20.011

HG80-2HG80

Fx rel. humidity of the air (process value)Fw adjusted humidity at the set value

generator (set value)

If the rel. humidity Fx falls below the adjusted set valueFw, then contact1/2 opens and contact 1/4 closes.

Adjusting the 2nd set value

The hygrostats HG80-2(i) are set by the factory such that the2nd set value is 6% rel. humidity higher than the 1st setvalue.The neutral zone (distance between the 1st and 2nd setvalue) can be adjusted after removing the housing coverusing a screwdriver. If turned to the left, the 2nd set valuegoes up (from 0%rh to +15%rh relative to the 1st set value).The neutral zone can be read using the rotary knob.

30

40

50

6070

80

90

100

% r.F.

2

4

1

2

4

1

1

<

Fx>Fw Fx<Fw

230VAC 15A

2 4

1

<

Fx>Fw Fx<Fw

230VAC 15A

2 4 2 4

1

ON

OFF

ON

OFF

30

40

50

6070

80

90

100

% r.F.

2

4

1

set value adjusting knob set value relativeto adjusting knob

approx. 5%rh

Fx Fx

approx. 5%rh approx. 5%rh

Set value regulatorleft-hand rotation >+range1 rotation = 2%rh

1. Microswitch

2. Microswitch adjustable from 0...+15%rh

30

40

50

6070

80

90

100

% r.F.

2

4

1

2

4

1

170 di 1

6,1

Ø

da 1

6,8

Ø

50 80

43

19 Ø 7 Ø

200

30 Ø

24 Ø

adjustable zonebetween the steps

120

228

300

16

30

BohrbildGabarit de perçageMounting drawing

80

107

68

5

5

20 35,3

7

Galltec

M20x1,5Cable gland

2nd changeover switchrelative to adjusting screw

1st changeover switchrelative to set value

regulator

JUCHHEIM GmbH & Co. KG • Ritterstr. 87 - 89 • D-42659 Solingen Datasheet 510 Page 2/4

Operating instructions for channel hygrostat HG80 and HG80-2

Mounting

The hygrostats must not come into direct contact withwater (e.g. splashed water when cleaning the climaticchamber etc.)The mounting location should be chosen so that arepresentative measurement of the air humidity canbe guaranteed, i.e. the humidity readings at themounting location should correspond to those in theroom as far as possible.The hygrostat should be exposed to the flow of air.

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Operating information:Note that, with restrictions in the upper range of operation,the possible tolerances (measurement accuracy,switching difference and temperature coefficient) shouldbe observed when adjusting the switch point.

MaintenanceThe measuring element is maintenance-free in pureambient air. Aggressive media containing solvent cancause measuring errors and failure, depending on the typeand concentration. As with almost all humidity measuringelements, deposits which eventually form a water-repellentfilm over the sensor are harmful. Such substances areresin aerosols, lacquer aerosols, smoke deposits etc.The water-resistant property of our measuringelements allows cleaning to be carried out in water. Solventscannot be used for this purpose. A light-duty detergent isrecommended, but any residue should always be washedout thoroughly.A special process ensures that our sensors havegood long-term stability. Regeneration is not necessary,but is also not harmful.

Equipment with our hygrostats is correctly set by thefactory at a room temperature of 23°C and 50% rel. humidity,relative to the average air pressure of 430m NN.

If, however, subsequent adjustment should be necessary,the following procedure should be observed.

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Exterior mounting

Preferred mounting positions

Ventilated sensor tube forimproved aeration order no. 20.022

Canvas blind for exterior mounting without solar cell order no. 20.024 with solar cell order no. 20.025

Condensed water must not get into the housing interior.

NOTE:Contact with the inner parts nullifies the guarantee.

Important. The water absorption capacity of the air isinfluenced, amongst other things, by the temperature. Thisis a physical law (which can be seen from the hx diagramof Mollier). The higher the air temperature, the greater thevolume of water vapour that can absorbed up to saturationpoint (100%rh). If a hygrostat is now calibrated at fluctuatingair temperature, there is an irregular, non-homogeneousmeasured medium and there are automatically calibratonerrors. The table below shows the influence of the airtemperature on air humidity. If, for example, calibrationoccurs at an air temperature of 20 °C and 50%rh, and at atemperature fluctuation of just ±1 °K, then there will be ahumidity fluctuation in the measured medium (air) of±3.2%rh.

Note:

Moving the adjuster screw nullifies the guarantee.

Ensure that the ambient humidity and the ambienttemperature are constant.

If possible, use a psychrometer for checking (no checkingequipment with capacitive sensors).

Leave the equipment to be checked for at least 1 hour ina constant checking climate.

The adjuster screw is at the end of the sensor - fixed withscrew securing lacquer. After removing the lacquer, theadjuster screw can be moved. A right-hand rotationmeans that the measured value goes down, and with aleft-hand rotation the measured value goes up. Aftercalibration, the adjuster screw should again be secured.

Calibration

50°C

±0,5%rh

±2,6%rh

±4,6%rh

30°C

±0,6%rh

±3,0%rh

±5,4%rh

20°C

±0,6%rh

±3,2%rh

±5,7%rh

10°C

±0,7%rh

±3,5%rh

±6,3%rh

10%rh

50%rh

90%rh

JUCHHEIM GmbH & Co. KG • Ritterstr. 87 - 89 • D-42659 Solingen Datasheet 510 Page 3/4

Maintenance regulationfor humidity measuring equipment with "Polyga®"humiditymeasuring element.

Impact of dirt

The measuring element is maintenance-free in pure ambientair. Aggressive media containing solvent can causemeasuring errors and failure, depending on the type andconcentration. As with almost all hygroscopic humiditymeasuring elements - and these include particularly thecapacitive measuring elements, resite measuring elementsand fibre measuring elements (Polyga) - are sensitive if awater-repellent film forms on the surface of the elements.Such sensors and hygrostats cannot be used for exampleduring wood drying as, depending on the type of wood to bedried, resin aerosols in the surrounding air are depositedon the measuring element. The same applies to lacquerdrying equipment where there are paint aerosols in thesurrounding air. Here, the psychrometer sensor (typeFEP3) has advantages in spite of the heavy maintenanceinvolved.The water-repellent property of our humiditymeasuring element allows cleaning to be carried out inwater. An important benefit33.

Cleaning instruction

for humidity sensors, hygrostats in channel design as wellas all shaft equipment, FG80.., TFG80.., HG80, HG80-2.

The humidity measuring equipment is designed with aperforated sensor tube. The humidity and temperaturemeasuring elements are in the interior of the sensor tube.The humidity measuring element is arranged axially and thetemperature measuring element is seated sideways at thetop or bottom between the perforation holes.Measuring equipment with Pt100 glass measuring resistorscan be immersed in water. Other temperature sensors, inparticular semi-conductor sensors or customer-specifictemperature sensors should not come into contact withwater. Enquire if in doubt.The measuring elements are designed for use inpressureless air (gases). The measurement accuracydepends on the degree of pollution of the element. Thehumidity measuring element, in particular, loses itshygroscopic properties if the surface is covererd with grease,soot, smoke deposits, paint, resinous substances etc. Bycleaning the elements, their function can be reproduced, butonly if no damage is caused by acids, alkaline solutions orother aggressive substances.

Cleaning process1. Dip the sensor tube into a receptacle containing cleanwater (20°C) and, with a gentle rotating motion, disperse thedirt deposits. If the dirt contains grease deposits, it isrecommended that a mild detergent be added to the water.

Do not brush or treat with any other cleaningutensils. Only the sensor tube should beimmersed - not the housing.

The sensor tube is open to the housing interior (0.8mmhole)

2. As mild detergents are known to contain chemicalsubstances, rinse carefully after cleaning. Cleaning residuewill impair the measured result.

3. Air drying. Where a measuring element is moistenedwith water, the device indicates 100% relative humidity. Ifnecessary, it is possible to carry out sensitive recalibrationat the adjusting spindle at the end of the sensor. Thisshould only be done where there are large deviations.Slight movement of the adjusting spindle of a wet elementcauses the measured value in the dry area to be badly out.Here, there is an intensifying effect of the linearisation(factor 6).Indications of 98..100% relative humidity at the wet elementare adequate.The accuracy in the dry area must be determined undernormal climatic conditions.

The measuring element must not be dried usingwarm or hot air (hair dryer).

Cleaning should be carried out for no longer than someseconds.

Cleaning instruction

for humidity sensors in room design, FG120.., TFG120..,HG120(-2), HGMini and equipment with an interiormeasuring element.

The units described above also apply to this equipment.

1. Unscrew the cover. Clean the cord shaped measuringelement using a soft brush and clean water. Do not use adetergent as it cannot be dispersed.

It is important that no water Is allowed to getonto the other components, particularlymicroswitches, terminals, printed circuit boards,potentiometers.

2. Air drying.Do not use warm or hot air (hair dryer).

Affects recalibration. See also the section for duct equipmentheaded Cleaning Instruction.

Installation Advises

On installation ensure that there is sufficient overcurrentprotection (e. g. fuse). Also a separation device (e. g. plugor switch) has to be installed.

December 1978 - revised December 2001

JUCHHEIM GmbH & Co. KG • Ritterstr. 87 - 89 • D-42659 Solingen Datasheet 510 Page 4/4