Repairing ESC Caps

[BHChieftain]

Hi,
I burned the caps on a fairly new seaking 120A ESC. The ESC will run for about 30 sec, then shut off. If I remove power, the unit will reset and will run again for about 30sec. I suspect the caps are now bad.

I want to try to repair the esc, and while I'm at it I want to add a cap board. I am thinking about these options:

1) Leave the damaged cap on the ESC and just install a cap board on the leads
2) Remove the damaged cap on the ESC and just install a cap board on the leads
3) Remove the damaged cap on the ESC, install a jump wire where the old cap was, and install a cap board on the leads
4) Replace the damanged cap on the ESC and install a cap board on the leads

The reason I would not just do #4 is I don't know where to find a replacement cap for the controller, so I was wondering if any of the other 3 options would work. If anyone knows a source for for a replacement ESC on the controller that would be great.


Chief

[Basstronics]

Replace the caps with new and add a few extras. The size isnt important, just the positive and negative legs.

I would get the bad caps off so they dont blow up.

[G-UNIT]

Whats the obvious signs of a bad cap, I have 3 t120 that are bad and just wondering if it is also the caps, 1 esc arms alright with all the beeps ect but no power to
the motor another one you can barley hear the beeps and no power to the motor and the last one starts to get hot when you just hook it up.
the caps look ok from what I can see but not sure.

[Insaniac]

Hi,
I burned the caps on a fairly new seaking 120A ESC. The ESC will run for about 30 sec, then shut off. If I remove power, the unit will reset and will run again for about 30sec. I suspect the caps are now bad.

I want to try to repair the esc, and while I'm at it I want to add a cap board. I am thinking about these options:

1) Leave the damaged cap on the ESC and just install a cap board on the leads
2) Remove the damaged cap on the ESC and just install a cap board on the leads
3) Remove the damaged cap on the ESC, install a jump wire where the old cap was, and install a cap board on the leads
4) Replace the damanged cap on the ESC and install a cap board on the leads

The reason I would not just do #4 is I don't know where to find a replacement cap for the controller, so I was wondering if any of the other 3 options would work. If anyone knows a source for for a replacement ESC on the controller that would be great.


Chief

Remove the old and replace with the bigger ones sold here on OSE...BTW, installing a jumper in place of the cap (option 3) is not a good idea...

cap-35v-1000uf_small.JPG

[BHChieftain]

Thanks, appreciate it!
Chief

[Joe Ford]

Whats the obvious signs of a bad cap, I have 3 t120 that are bad and just wondering if it is also the caps, 1 esc arms alright with all the beeps ect but no power to
the motor another one you can barley hear the beeps and no power to the motor and the last one starts to get hot when you just hook it up.
the caps look ok from what I can see but not sure.

#1 is not caps...it's an issue with the output side of the power board on the ESC. Most likely FET drivers. Or plug in different motor...the only other reason for no power to motor and low audible tone. #2 could be a lot of things, but also not caps. Most likely a connection being made where it shouldn't be. Caps usually have a bulging end, brown syrup-like material sometimes coming out of them (electrolytic fluid), or they're just plain blown open.

BH...you probably already have your answer, but I would be surprised if this were the capacitors. It sounds like a component may be reaching a certain temperature and shutting down.

TECH TIP: Better to use several smaller caps than one large one. They fill and dump faster. Think of it like a battery pack. You can charge it and discharge it faster. It's easier on the electronics (as long as you have enough capacitance obviously).

(Hoping mods don't get mad for offering general tech advice)

[Basstronics]

What about combined ESR?

All caps are 1 time constant discharge and 5 time constant charge.

I guess I dont understand how multiple caps fill and discharge faster than a single larger cap since the time constant formula pertains to all. If anything I would think its a modular situation since none of us want a 1 Farad cap in our boats.