Altrax SPM-500 - Pre-charge resistor error code

[klanel]

I am getting 1 green/6 red which supposedly indicates a pre-charge resistor failure. I measured a 2v voltage drop across the resistor but to make sure, I disconnected one side and ohmed it out to .475K so unless the tolerance is too far off of .470k that is not the issue.

Error light does not start blinking until I press the accelerator down about 1/4 of the way. Just the throttle switch closing alone does not cause it to error.

I'm wondering if the controller may have an issue but it will be next week before I can get in touch with Alltrax.

By the way, their software seems to be lacking or its the old computer (XP) I'm trying to run it on. V2.1.8

[scottyb]

Sounds like a controller fault. Just for grins can you try another resistor, off your old system (any value)

[klanel]

Originally Posted by scottyb

Sounds like a controller fault. Just for grins can you try another resistor, off your old system (any value)

Don't have another to try but I decided to program for less current than the default 500a on the motor and battery that was default to see if the controller would still see a pre-charge error. It did but when I changed some other settings for ksi input voltage and low batt voltage then I quit getting the precharge error and got a low batt error.

While monitoring, when I press the accelerator and engage the switch, shutdown becomes active, then if I press down more it shows the precharge coming active.

I did manage to get it to move once in reverse and once in forward. I think my motor/controller/fr wiring is correct. If it wasn't would there be any possibility that it could go forward/reverse at all? I have no expertise with motors. Also don't really know what settings I should be using on the Alltrax, the only ones I initially changed were for the throttle (2w/0-5k) and lowered reverse speed to 20%.

[scottyb]

2 wire 0-5k would be used for a potentiometer throtttle device only - not a Vglide or MCOR

[klanel]

Alltrax says pre- charge failure occurs when B+ voltage is 6v or more below key switch voltage at ksi input on controller. I will look again this evening but I did notice a 1v drop across the solenoid when closed. Seem like a lot of resistance through a closed contact. And the connections are pretty tight. That would account for 1 of the 6 volts.

[scottyb]

Keep us posted

[klanel]

Got the cart running by jumpering across the resistor. However, when I got home today to work on the 'pre-charge' alarm I got a low battery alarm instead except the battery voltage on their software and measured at the b+ and B- on the controller were showing good voltage.

After riding it around the yard a little while with the jumper across the resistor, I took the jumper off and it started giving just the 'pre-charge' alarm again. Plugged my computer back in and when I enabled the throttle switch and pressed the accelerator it started working properly, this time with no jumper.

So to summarize, (or try)

I have been getting various alarms that prevent running when I didn't change anything.
For a couple of days, a 'pre-charge' alarm but the resistor is good and voltages were well within tolerance.
Jumpered across the solenoid contacts to bypass the resistor and it started working.
Quit working when I removed the jumper later began to work without the jumper.

Alltrax says to change the resistor which I will do, but in 35+ years involved with electronics, I have never seen an intermittent resistor. They almost always open but can short if it gets charred enough.

Have a year left on the warranty (took a year to build) so if it is an intermittent issue with the controller hopefully it will get resolved. Either work or die.

Anyone else encountered similar intermittent and unexplainable issues with an Alltrax?

[scottyb]

Alltrax has the best warranty record in the industry period. Humor them, get a resistor & try it.
I think you need to contact your dealer for return authorization. That unit is buggy

[klanel]

They did not offer or suggest me sending it back, just to try another resistor which I have already ordered. If it was always just a pre-charge alarm I'd feel more at ease than with the symptoms changing.

Will see what happens as time goes on but I will be carrying a jumper with me in case it decides to quit somewhere.

PS: You were the dealer. Bought it May 1, 2015 I believe but we can see if the issue clears.

[scottyb]

Originally Posted by klanel

They did not offer or suggest me sending it back, just to try another resistor which I have already ordered. If it was always just a pre-charge alarm I'd feel more at ease than with the symptoms changing.

Will see what happens as time goes on but I will be carrying a jumper with me in case it decides to quit somewhere.

PS: You were the dealer. Bought it May 1, 2015 I believe but we can see if the issue clears.

Well then - Just ask and I will authorize a factory once over for repair or replace. No problem I just can't tell who's a customer and who's not with the usernames....send me a pic of the ID tag in email with your request.