Need some help with Curtis ET 134 and SPM 72400


I have a question that is going to get quite long winded, I hope y’all have the time to help me out.

Ok, so I am putting an electric motor in my boat to be used in the no wake zones.

Alltrax SPM 72400 motor controller.
Curtis ET 134 throttle.
6x 12v Dual AGM Deep Cycle batteries, 70ah.
Albright Reversing and Main contactor
400amp Fuse
ME 1003 Motor

I have wired the curtis throtte using this URL TAKEN DOWN manal, the last diagram, Making one small change. I have pin 1+7 wired up to battery 1 negative and pin 2 to battery 2 positive. This is to give me 24v (the throttle is 24-48v). When I connected them to B- I got 72v from the ‘‘To system wiring’’

Now the SPM turns on, but I have the following issues with it.

The Main contactor does not engage, but I get 55v at the controller terminals. I’m guessing that it because of the precharge resistor? This then gives me an undervoltage error, I corrected that with the software, lowering the undervoltage limit to 50v.

If I engage the contactor manually, I am able to get 74v at the terminals and the controllers LED lights up with 3 green flashes, indicating a 0-5v throttle. Problem is that if I try to move the throttle I get 2 green and 3 red, High Throttle Over Voltage. When I try use the multimeter on the voltage output on the throttle I get 0-5v (0,01-4.98v) But if I try a at the controller, positive to the plug and negative on the high throttle pin I see 25.2v.! I get the same result if I put the negative prod on the B- on the controller. The throttle indicator within the alltrax software sees 0% throttle when it not moved, but jumps to 100% right away.

BTW, the throttle and reversing contactor get kind of hot. But again, everyting is wired acording to the literature(except for the ones going to B-)

Is there anyone out there who knows how to fix this?



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