Ground sparking (in tow) when removing cable

[GolfMechanic]

2011 Club Car Carryall 2 (48V)
S/N: QB1117-190607

I'm trying to remove the negative battery cable off of battery 8 but when I try to remove the cable I get lots of sparks until I tighten back down the cables again. Key switch is in "off" position and run/tow switch is in "tow." The Drok step down converter is also attached to this same negative battery terminal. My 12 Volt circuit is working fine. Do these Drok converters break often or should I suspect the tow/run switch is to blame? Or is there somewhere else I should look?

[Mooncarter]

Hook the neg. cable up without the converter cable and see what happens.

[Mooncarter]

Some sparking is normal when you hook up the voltage reducer.

[GolfMechanic]

Originally Posted by Mooncarter

Some sparking is normal when you hook up the voltage reducer.

So after closer inspection of the converter, it turns out the converter is always powered (meaning converter bypasses run/tow: battery power -> converter -> battery negative). This is different from all our other club cars. Our other converters have a sensor wire to tell it to turn on/off but this one doesn't :/ I'm thinking about either tying the power lead from the converter to the run/tow switch or just putting in a separate toggle switch on the converter's 48V ground to turn the converter off.

[Mooncarter]

Toggle will work. I don't know about the run/tow.

[Mooncarter]

BTW, a lot of people hook the neg. to B- on the controller so the OBC can monitor the voltage reducer usage.

[Tom47]

Originally Posted by Mooncarter

BTW, a lot of people hook the neg. to B- on the controller so the OBC can monitor the voltage reducer usage.

This is the correct way to do it. And a doublepole, single throw toggle switch will disconnect the Pos and Neg at the same time.

[GolfMechanic]

Thanks for the quick advice you guys! Much appreciated.