Keep frying Solenoid at Slow Speed

[Sougentlmn0140]

I have a 36V EZGO...New Batteries. The Volt Meter Drops from above 36+ to mid -20's when under a load....all batteries & cells tested...all good.....Hogh Performance Motor & Alltrax 500A Controller....any ideas?

[DaveTM]

https://www.buggiesgonewild.com/showthread.php?t=3915Do you have a series motor or a Sepex motor....how to tell:

[bronsonj]

First assumption, you are replacing the solenoids with a heavy duty golf cart solenoid, right? A standard duty golf cart solenoid was barely adequate for the stock controller and an automotive duty solenoid is nowhere near what the cart needs.

When you say it drops to mid 20's under load is that just the load of moving the cart or is that pulling something or mashing the throttle trying to go up hill?

That much of a drop tells me you either have a heck of a load or have some issue in the high current circuit. Have you checked for heat buildup in any of the cables after doing a run with a heavy load?

Fully charge the batteries and disconnect them from the charger and let the cart sit for about a dozen hours. Then measure the voltage of each battery. That's your gold-standard at rest voltage measurement. Then measure the full pack voltage before attempting to accelerate to full speed on flat ground. Also measure the voltage while accelerating.

Or, if you have a newer Alltrax controller you can just do a data log and it captures all the pertinent information and more.