Frame Voltage?

[DanGoneWild]

Looking for a little insight from you electrical gurus. So my Alltrax XCT48500 controller is reading 55 Volts coming from my battery pack on the monitor page of the software but the B+ side of the controller reads 42 Volts with a handheld voltmeter. Problem is it's a 36 Volt battery pack. The most frustrating part is on occasion, it will go in to safe mode giving me the over voltage alarm even when setting the max volts receivable as high as it will go (62).

I contacted Alltrax and they said "there has to be something wrong with the controller, or you have standing voltage on the frame of your cart (which I haven’t seen affect XCT controllers before but it’s possible)."
They've been very helpful up to this point and they have offered to do testing... which looks like the direction I will go since it's still under warranty. That said, before I send the controller to them, if I were to assume the problem is standing voltage, how would I test that? I put the - probe of my voltmeter on the - battery terminal and + probe to the frame and get nothing.

[JohnnieB]

Make the voltage measurements with the black test lead on the XCT's B- terminal to duplicate what the XCT is seeing.

Do you have a "Regen Diode" installed between the solenoid's large terminals,or is there a 250Ω resistor installed instead? (Should be the diode)

Is the cable that goes to the motor's A2 terminal connected to B+ at the controller's B+ terminal or at the solenoid's controller side large terminal? (Should be on XCT's B+ terminal)

[DanGoneWild]

Originally Posted by JohnnieB

Make the voltage measurements with the black test lead on the XCT's B- terminal to duplicate what the XCT is seeing.

Do you have a "Regen Diode" installed between the solenoid's large terminals,or is there a 250Ω resistor installed instead? (Should be the diode)

Is the cable that goes to the motor's A2 terminal connected to B+ at the controller's B+ terminal or at the solenoid's controller side large terminal? (Should be on XCT's B+ terminal)

It appears the Regen Diode is installed between two small screws next to the large terminals and the 250 ohm resistor is installed between the large terminals. Unfortunately I'm not 100% sure at what I'm looking at though. Still a newbie. I'll try to send a picture as soon as I can.
As for the motor's A2 terminal to B+ controller terminal, yes that is the way it is wired.
EDIT- I put the black test lead to the XCT's B- and the red to the frame and got no voltage reading.

[JohnnieB]

Originally Posted by DanGoneWild

It appears the Regen Diode is installed between two small screws next to the large terminals and the 250 ohm resistor is installed between the large terminals. Unfortunately I'm not 100% sure at what I'm looking at though. Still a newbie. I'll try to send a picture as soon as I can.
As for the motor's A2 terminal to B+ controller terminal, yes that is the way it is wired.
EDIT- I put the black test lead to the XCT's B- and the red to the frame and got no voltage reading.

There should not be a resistor between the solenoid's large terminals.

There should be a diode between the small terminals (Suppression diode) and a second diode between the large terminals (Regen diode). See the attached schematic.

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Remove the 250Ω resistor and try it.

[scottyb]

It should have a diode on both small and large posts... like this document attached