Running an ESC with a blown Capacitor.

[Hardcoretam]

I posted a comment about this in another thread that was huge so wanted to try and get some more ideas / opinions on stuff.

I've a Hobbywing ESC, with a built in capacitor.
I had a bad bump in my truck the other day and for one reason or another, after the bad bump, i heard a loud and short "hiss" like a tyre going down rapid.

On inspection, the capacitor on the ESC had swollen slightly at the top (bevelled outwards, rather than inwards), and had leaked a little fluid.
Truck still appeared to drive and perform fine. ESC, battery and all other components were cool to the touch.


My question is, as i can't replace it and i can't afford a replacement at the moment, is there any danger from running the truck? (provided there is no shorts anywhere ) or is the capacitor required for long term "safe" use?

[JatoTheRipper]

You posted this elsewhere. Did you contact HobbyWing? They might even replace the ESC if it's new.

[mikemcE]

So the quick question is how long before something roasts ?
Not long I suspect as once a cap has failed, no filtering spikes and the next one could cook things. Your rig call the mfgr , replace it , or keep your fingers crossed it's only the esc !


Hang up and Drive

[Hardcoretam]

Originally Posted by Hardcoretam

I posted a comment about this in another thread that was huge so wanted to try and get some more ideas / opinions on stuff.

Originally Posted by JatoTheRipper

You posted this elsewhere. Did you contact HobbyWing? They might even replace the ESC if it's new.

As above, that was just a comment within a thread and thought a specific thread would get some more opinions.

It's a few months old now, but no warranty as i've changed the standard XT-60 connector so i'd imagine that voids it.
I'd bought it via Hobbyking as well via a UK warehouse, rather than Hobbywing direct.

Originally Posted by mikemcE

So the quick question is how long before something roasts ?
Not long I suspect as once a cap has failed, no filtering spikes and the next one could cook things. Your rig call the mfgr , replace it , or keep your fingers crossed it's only the esc !

Is the capacitor to prevent voltage spikes to the BEC?
I've emailed Hobbywing, but awaiting a reply still.

[JatoTheRipper]

Originally Posted by Hardcoretam

As above, that was just a comment within a thread and thought a specific thread would get some more opinions.

It's a few months old now, but no warranty as i've changed the standard XT-60 connector so i'd imagine that voids it.
I'd bought it via Hobbyking as well via a UK warehouse, rather than Hobbywing direct.

I'd contact your local HobbyWing rep first or maybe HobbyWing directly. If they say no I'd still try with HobbyKing. You'll probably get nothing out of it, but it's worth a shot.

If the capacitor is done either attempt to solder a new one on by yourself which is difficult by itself and might be impossible with the waterproofing material.

Or run it until it pops. It's dying anyway.

[Hardcoretam]

Originally Posted by JatoTheRipper

I'd contact your local HobbyWing rep first or maybe HobbyWing directly. If they say no I'd still try with HobbyKing. You'll probably get nothing out of it, but it's worth a shot.

If the capacitor is done either attempt to solder a new one on by yourself which is difficult by itself and might be impossible with the waterproofing material.

Or run it until it pops. It's dying anyway.

Sadly Hobbywing don't have local reps in the UK (or if they don,t find any) so i need to deal directly with China.
Hobbyking where i bought it from does though so will give them a contact as well and see if they can help.

I can handle the ESC dying i guess, but if it took out the servo light controller, lipo etc that would be annoying.

[JatoTheRipper]

Originally Posted by Hardcoretam

Sadly Hobbywing don't have local reps in the UK (or if they don,t find any) so i need to deal directly with China.
Hobbyking where i bought it from does though so will give them a contact as well and see if they can help.

I can handle the ESC dying i guess, but if it took out the servo light controller, lipo etc that would be annoying.

Warranty explanation:
After-sales Service Policy_After-sales Service Policy_HOBBYWING | Welcome to Brushless System Trends -

UK distributor per this link:
Distributors_Distributors_HOBBYWING | Welcome to Brushless System Trends -

United Kingdom
Schumacher Racing Products Ltd.
Rob Foster
+44 (0) 1604 790580
info@racing-cars.com
Schumacher RC Racing - World leading manufacturer of R/C Cars | Trucks.
Ezrun,Xerun

[Hydrocarbon92]

With it gone it will increase the load on the ESC, but it's really up to the ESC's design to tell if it will last or not. The large external caps (by that I mean not on the PCB) are generally for easing the load on the ESC. The battery may provide a lot of amps but a big cap still helps with momentary inrush demands, sort of how a suspension still benefits from a pneumatic tire.

First I'd recommend you remove the blown cap. If it's waterproofed into it, you have to decide if you can remove it completely or not. Usually you can pull it like a loose tooth. If it's the cap connected to the battery leads, which is likely, you can get almost any "glitch buster" cap and wire it to the battery leads in it's place. Ideally you'll use a "low ESR" cap, but it's not imperative if you intend on replacing the ESC eventually.

[Ninomaniac]

If you pull the cap like a tooth, there's a possibility that the leads will stay behind, sticking out of the board. In that case they can be used to connect the new cap.

[Hardcoretam]

Originally Posted by Hydrocarbon92

With it gone it will increase the load on the ESC, but it's really up to the ESC's design to tell if it will last or not. The large external caps (by that I mean not on the PCB) are generally for easing the load on the ESC. The battery may provide a lot of amps but a big cap still helps with momentary inrush demands, sort of how a suspension still benefits from a pneumatic tire.

First I'd recommend you remove the blown cap. If it's waterproofed into it, you have to decide if you can remove it completely or not. Usually you can pull it like a loose tooth. If it's the cap connected to the battery leads, which is likely, you can get almost any "glitch buster" cap and wire it to the battery leads in it's place. Ideally you'll use a "low ESR" cap, but it's not imperative if you intend on replacing the ESC eventually.

With my gearing and my truck and wheels etc, the ESC has never even got luke warm before when running it hard on 3s so i'm hoping as i don't draw many amps with my set up and running, that it will last a bit longer if i just keep an eye on the heat whilst there is no cap. I'm a conservative driver and don't get in binds or the likes.

Originally Posted by Ninomaniac

If you pull the cap like a tooth, there's a possibility that the leads will stay behind, sticking out of the board. In that case they can be used to connect the new cap.

It's an awkward case. Someone tried to remove the casing and it's virtually impossible without cutting it off and destroying it and the heatsink.




Unless i maybe pull that one off,seal the hole that's left with rubberised silicone to prevent any shorts from left over capacitor bits then just solder in another capacitor where the XT-60 is soldered.

Funny enough the 1080 ESC in the picture above, uses a different capacitor to mines.

[CoolRunning]

You might want to be careful running it without a cap. From what I've read, the cap is there is filter and protect the FETs and brushed relies more heavily on the cap than brushless for this filtering.

I've ready you can add capacitance by running (taping) your battery to ESC wires close which helps there. If by any chance you have long wires here and they are not close together this can work the cap harder. It may simply be a failure though the above can make a difference especially with the voltage spikes a brushed motor might generate in a bind etc.