Test Jig for NS2 Regulator
Installation and Operating Instructions
12, 24 Volt Models August 28, 2008



The NS2 Test Jig is a special PCB assembly made just to test NS2 regulators. The Test Jig is to be used only by persons who are competent electronic technicians and familiar with the features and functions of the NS2 Regulator.

The Test Jig will test all NS2 regulators. Some restrictions are noted later in this document.

No technical support is provided for the Test Jig.

Power Requirements

The Test Jig is designed to take an input of 12 to 13 Volts ...a typical 12V battery voltage. A DC-DC converter is used to boost the input voltage sufficiently to test the NS2 under usual operating voltage.

The boost converter is not capable of driving external field loads such as an actual alternator. Testing a regulator under full load is not normally required, however, the Test Jig can be wired to do so if deemed necessary.

The output of the boost converter can be selected to be 16, 32, or 40V. A switch is provided to select 12/24 Volts (16/32V B+). To generate 40V to test 32V regulators the switch is placed in the 24V position and a jumper is installed across the 32V header.

A 12/24V NS2 can be tested at 16 or 32 Volts depending on its end use.

Test Points

Test points are provided that accept normal multi-meter probes. The three test points on the middle left of the Test Jig are B+, GND, and Regulator Feedback. B+ is the voltage from the boost converter and depending on the switch and jumper should read approximately 16, 32, or 40 Volts.

The Regulator Feedback test point is the voltage that the NS2 generates when it is regulating.

There are also two test points to measure the signals that drive an Alternator Driver module. They are labelled REG2-Z and REG2-Y.


Five toggle switches are provided. Indications are given for the Up/Down position of the toggle handle.

The switch labelled SENSE is used to disconnect the sense input from the NS2.

A second switch selects whether B1V-IN to the regulator comes from a potentiometer on the Test Jig, or feedback from the regulator field output signal.

A switch labelled IGN1 is used to enable/disable alternator regulation.

Another switch labelled IGN2 is used to enable/disable output to the Alternator Driver module.

The last switch is used to select 16/32 Volts for testing 12/24 Volt regulators.


Two potentiometers are provided. Both are 20 turn pots.

One pot is used to set the temperature read by the NS2 as B1T.

The second pot sets the voltage that the NS2 senses if the Sense Select switch in on the Pot position.

Push Tab Connections

Four push tab connectors are provided to supply power and ground to the Test Jig. Field is also routed to one of the push tab connectors to be used for high current testing.

DB9 Connector

A DB9 connector is provided to facilitate testing NS2 Regulators which have the serial port option. The pins are swapped as necessary to interface directly with a PC, using a straight through cable.

Wiring Diagram

The wiring diagram is shown below.

A fuse and On/Off switch should be installed close to the battery as shown. A fast blow fuse of 1-3 Amps is appropriate.

The Test Jig is connected to the NS2 Regulator with 16 wires that connect point to point across the terminal blocks. Length of the wires is not critical, but allow several inches so that nothing is stressed by the wiring.

A high capacity battery is not required because the total draw is low. The optimum voltage of the battery is about 12.5 Volts. The only thing on the Test Jig sensitive to the input voltage is the voltage fed to the battery temperature input on the NS2 regulator.

Operating the Test Jig

Initial Setup

Toggle the four switches near TB1 and TB2 to the off position so that the handles are toward the DB9 connector.

Before connecting an NS2 to the Test Jig, apply power and verify that B+ is correct for the regulator to be tested ...for example about 16 Volts for a 12V regulator.

Plug in TB1 between the NS2 and the Test Jig and verify that B+ is not changed. If there is a significant voltage drop, the NS2 should be returned to the factory for repair.

Plug in the serial port to the PC if testing a regulator with the serial port option.

Measure the voltage on TB1-6 and adjust it using the B1 Temperature potentiometer to read 2.98 Volts which corresponds to a temperature of 25$^\circ$ C.

On the NS2, and using instructions in the NS2 Installation Manual, adjust the absorption setpoint potentiometer to 1.44 Volts at the absorption testpoint. Adjust the float setpoint to 1.35 Volts and the time setpoint to 1.2 Volts. The NS2 is now ready to test.

Regulation Testing

Measure between the Regulator Feedback testpoint and GND. The meter will display a voltage which is provided by the test jig to represent a deeply discharged battery. It should be less than 12/24 Volts.

Turn the Sense switch on, and the Sense Select switch to the Reg position. Now turn on the Ign1 switch. The meter should now show a gradual increase in voltage as the NS2 ramps up field output. The ramp-up stops when the internal setpoint reaches the float voltage.

After ramp-up is completed, the NS2 should step through float and gassing voltage plateaus until it finally goes to the absorption setpoint.

Setpoint Calibration

Measure the absorption setpoint test point on the NS2 and compare it to the voltage measured on the Regulator Feedback test jack. The ratio should be 10:1.

The float setpoint can be tested in the same way, however, power to the Test Jig and NS2 will have to be cycled to get the regulator to go through the float voltage again.

Sense Testing

With the NS2 regulating, turn off the Sense switch and observe the output. The regulator will generate full voltage for a few seconds until it raises a No Sense error.

The NS2 should recover when the Sense switch is turned back on.

Temperature Sensing Testing

Slowly vary the B1 Temperature potentiometer up or down and verify that the Regulator Feedback changes. There may be some delay between pot adjustment and the change at the output.


Battery Combiner Testing

If the Battery Combiner option is enabled it can be tested.

Shortly after the NS2 output exceeds 13/26 Volts, the orange Battery Combiner LED on the NS2 should illuminate.

Turn off the Ign1 switch to turn off the regulator. The orange LED should extinguish. Now select the Pot input to the NS2. Measure the voltage on TB1-4 and adjust the B1V Adjust pot above 13/26 Volts. After about 30 seconds the orange LED should illuminate.

The B1V Adjust pot can be very slowly turned down to check the drop-out voltage for the Battery Combiner signal.

Two Alternator Testing

The Two Alternator option can be tested using the Test Jig.

Put the meter on the AC scale and insert the leads into the Test Jig jacks labeled Reg2-Y and Reg2-Z. The meter should read essentially zero.

Now turn on the Ign2 switch. The meter should show AC voltage greater than 1.5 Volts.

Testing the Serial Port Option

By providing a DB-9 connector, the Test Jig makes it convenient to test the Serial Port. A straight-thru cable with male/female connectors is necessary.

Place one end of the cable into the Test Jig, and the other into the PC. Activate a terminal emulator program and set it up to operate at 19,200 Baud, 8 data bits, 1 stop bit, no parity, and flow control set to none.

Hit ENTER a couple of times and then type the following string, adding an ENTER at the end of it.

The NS2 should respond with the voltage present a TB1-4.

Refer to the manual for the RAP Protocol as well as the manual covering the NS2 Serial Port for further information.

Testing Under Full Load Conditions

We have yet to see an Ample Power regulator which works with a test jig but fails under full load. However, testing under full load conditions is possible. Disconnect the B+ wire in pin TB1-1 of the NS2. A power supply positive lead can now be wired to the NS2 on TB1-1. The power supply negative is then connected to the other GND push tab of the Test Jig.

A load, such as an alternator field coil, can be connected to the FLD push tab on the Test Jig. The other end of the load must be tied to ground.

With the power supply set at 16/32 Volts the regulator can now be tested as previously described above.

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


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