Next Step Alternator RegulatorInstallation and Operating Instructions

Ample Power Models NEXT-12P and NEXT-24P July 24, 2000

Mounting the RegulatorThe regulator is protected against ambient humidity, but must bemounted in a dry location free of moisture, dust and other environ-mental insults. The regulator will operate in temperatures to 70 C(158 F).

Wiring DiagramThe wiring diagram above is the only way to wire the Next StepRegulator. Do not wire in any other way, such as combining groundwires or battery positive wires. Use fuses where shown. Failure todo so may result in fire.

Signal Names and FunctionsBattery voltage set-points are specified for each voltage system, 12or 24 volts, as 12 / 24 volts, respectively.

PARALLEL, (optional) . . . a grounding signal that is assertedafter 30 seconds and when the regulator detects that thehouse battery is being charged.. Maximum load is 0.75Amps.

ON / OFF, (required) . . . a positive voltage that turns on theregulator. Typically it is connected to the ignition switch oroil pressure switch. Typical draw is 0.03 Amps.

NOTE: On gasoline engines DO NOT connect at thespark coil . . . connect at the ignition switch.

GROUND, (required – connect this wire first) . . . the refer-ence ground for the regulator. All battery voltages are refer-enced to this wire.

B , (required) . . . The source of power for the alternator fieldcurrent. Amperage draw on this wire is rated at 15 / 8 Ampsmaximum.

FIELD, (required) . . . the wire driven positive by the regula-tor to make the alternator charge. Voltage at this point de-pends on how much current is being produced by the alter-nator, and varies from zero to battery voltage.

ALT.GND, (required) . . . the return line for field current.WARNING: Do NOT jumper this wire to the GROUND

tab. Absence or loss of this connection will damage theregulator.

LOCK, (optional) . . . if connected to battery voltage, the reg-ulator is locked at battery gassing voltage, typically 13.8 /

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27.6 V. Used to prevent higher voltages when halogen lightsare used. The first activation and then removal of the LOCK

signal causes the regulator to go to the float set-point. Thesecond cycle causes the regulator to go to the absorption set-point. This cyclic behavior repeats.

BAT.VOLTS, (required) . . . the sense wire for battery voltage.Any erroneous voltage drop in this wire from the battery cancause overcharge.

T- (BLK), (optional) . . . ground side of the temperature sensorwhich is supplied with the regulator.

T+ (RED), (optional) . . . positive side of the temperature sen-sor. Voltage at T+ (RED) is 2.98V at @ 25 C (77 F), andvaries plus and minus with temperature at the rate of 0.01Vper degree C.

ABS, (optional) . . . a positive voltage at ABS will lock the reg-ulator at the absorption set-point. Typically used with theAmple Power Energy Monitor/Controller.

LAMP, (optional) . . . a ground going signal that providestroubleshooting information identical to the Red Error LED. . . see the Error Indicator section. Maximum current permittedfrom this output is 0.75 Amps.

State IndicatorThe green LED shows at which set-point the regulator is presentlyoperating. Status is shown by flashing the green LED with On andOff time in seconds as shown below.

Table 1. Green Status LEDStatus On Off

Bulk Charge 2 1Absorption Charge 1 1Absorption Charge & OK to Adjust continuous N/AStep to Float 3 3Float Charge 2 2Gas Lock 3 1ABS Hold 1 3

Error IndicatorAbnormal conditions are reported with the Red LED, and the ex-ternal lamp/alarm, if wired. Errors are identified by On and Offtimes of the Red LED as shown below.

Table 2. Red Error LEDError On Off

Can’t turn field off 1 1Can’t turn field on 1 3Bat. Volts disconnected 3 1Over Temperature 3 3Voltage Runaway 6 3Bad Temperature Sensor 6 6

Voltage AdjustmentThe factory setting is 14.4 / 28.8 Volts. The float voltage is 0.8 / 1.6Volts less than the absorption set-point. Before adjusting absorp-tion voltage disconnect the T+ (RED) connection from the regulator.

Absorption voltage can be adjusted by turning the small screw onthe potentiometer behind the hole in the cover marked ABSORP-

TION VOLTAGE. The potentiometer is 20 turns. Turn in small incre-ments and wait at least 3 seconds for the adjustment to take effect.Do not adjust the potentiometer unless the green LED is oncontinuously.

Absorption Time AdjustmentHow long the regulator stays in absorption state is factory set atone hour. It can be changed from 0 to 255 minutes by turning thepotentiometer behind the hole in the cover labeled TIME. To makethis adjustment convenient, a multi-meter can be used. Place thepositive lead in the TIME TEST POINT located within the regulatorcover, and the negative lead on ground. Time is read on the multi-meter voltage scale where every 0.02 Volts is equal to 1 minute ofabsorption time. Factory setting is 1.18 Volts.

What You Should SeeWhen the regulator is first turned on, the red LED will glow for 5to 8 seconds before extinguishing. The alternator should start tocharge after the red LED goes off. Then the green LED will startto flash status information. For example: 2 seconds on, 1 secondoff, (bulk charge).

Alternator RequirementsThe alternator must be an externally regulated model with onebrush connected to ground and the other brush fitted with a con-nection to make the field connection, (P-type). Be advised thatalternators not hot rated for continuous operation at high cur-rent and temperature may fail when driven by the regulator.

TroubleshootingFirst, look at the Signal Names and Functions section above and makesure that all required wires are in place and properly connected.We have found that moving a wire such as BAT.VOLTS or GROUND

a few feet away from a good Battery Positive or Negative Distri-bution could result in undesirable regulation due to voltage spikesin the system. To help diagnose voltage set-points, remove the T+

(RED) connection to prevent a faulty temperature sensor from af-fecting the system.Second, if the problem still exists, obtain a copy of the NextStep Troubleshooting Guide which is available from the followingsources:Regulator Service Center

Web: http://www.amplepower.com/support/

E-mail: support@amplepower.com

Phone: (206) 789-4743 or Fax: (206) 789-9003

The troubleshooting guide was designed to help isolate a majorityof the installation problems. Fill out the Troubleshooting Guide todetermine if all measurements meet the specified requirements.

Finally, if you are unable to remedy the problem, contact the reg-ulator service center with the Next Step Troubleshooting Guidecompleted for referencing.

Ample Power products are manufactured by Ample Technology, 2442 NW Market St., #43, Seattle, WA 98107 – USA

Visit http://www.amplepower.com

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