Kelly KLS-S 72v controller wiring

[agniusm]

I have this controller and wiring diagram shows contactor. Would it be ok to wire it without contactor or would it drain the battery? Those chickers ar bulky and i would rather not use it. My intuition tels me that in most cases fuse would suffice?
I do not dischargw through bms and my bms P- drives contactor coil usually. I would like to fit small relay instead to controll ignition wire on the controller.
Also, is there a better android app as stock one is total garbage at least on a smartphone

 

[2WheelsMovesTheSoul]

You can skip the contactor. A fuse is good enough. This is directly from Fany @ Kelly.

You still want to use the big green resistor that came with the controller anytime you connect the battery to the controller. This will help to slowly fill the capacitors in the controller and also help reduce the chances of spark when making the final connection.

You can use a relay to switch on the bike, but beware at 72v most cheap 12v automotive relays won't last too long. Doesn't matter if its rated for 100 amps or 10 amps, the spark will prematurely wear out the contacts or sometimes spot weld them together which could be very bad. Look for high voltage DC relays instead.

As far as the APP goes, I agree. It's garbage, I have a feeling it works best on that overpriced $99 tablet with "pre-loaded software" they keep trying to pawn off. I've tried it on several phones and it's always the same, a big chunk of the info/status bar is cut off. I used the PC version to copy all that missing info from the BT APP so I could make adjustments on my phone. The APP is meant for a full sized PC they finagled the software just enough for it to be semi-functional on BT.

 

[agniusm]

You can skip the contactor. A fuse is good enough. This is directly from Fany @ Kelly.

You still want to use the big green resistor that came with the controller anytime you connect the battery to the controller. This will help to slowly fill the capacitors in the controller and also help reduce the chances of spark when making the final connection.

You can use a relay to switch on the bike, but beware at 72v most cheap 12v automotive relays won't last too long. Doesn't matter if its rated for 100 amps or 10 amps, the spark will prematurely wear out the contacts or sometimes spot weld them together which could be very bad. Look for high voltage DC relays instead.

As far as the APP goes, I agree. It's garbage, I have a feeling it works best on that overpriced $99 tablet with "pre-loaded software" they keep trying to pawn off. I've tried it on several phones and it's always the same, a big chunk of the info/status bar is cut off. I used the PC version to copy all that missing info from the BT APP so I could make adjustments on my phone. The APP is meant for a full sized PC they finagled the software just enough for it to be semi-functional on BT.

Thanks. You can get 72v rated relays no problem. I also thought about using SSR or mosfet. Maybe. I do use resistors on the builds always unless i want black terminals :lol:
I will try the app on a tablet. Perhaps bigger screen will help as its PITA with wires when you cant use BT