Emax Lightning BLHeli ESC

Hi Guys,

Quick question. Is it necessary to fit a good quality electrolytic capacitor directly across the power feed into these ESC’s? (As some other ESCs already have fitted)

I have some 470uF 16V handy and am only hesitating as they’ll be a tight tight fit…



(EDIT) Just to add: I always prefer if there’s a contact telephone number for a quick question like this. Relying on tech support forums as the only means of support is (a bit lazy - sorry!) as forums can often be so sloooow…

I’m left wondering whether I should order some more of these (I have another three drones to build) or go for something entirely different? Alex? What’s your considered opinion please? Anyone else with experience of this particular ESC?
I’m particularly concerned about possible noise being fed back onto the battery power rail.

It really depends on your setup, as sometime if you are using beefy motors with active breaking on a 4S setup sometimes the voltage spikes can cause damage to something like your VTX. However if you are already using an LC Filter on the fpv power line then you should not need to add an extra cap which is abit neater than a capacitor on each esc, but of you got space, why not :stuck_out_tongue:

As for phone support, we did have this as I know that it’s great from a customer point of view. But with only two of us working we had no time to order stock, send orders and add new products and write guides, market products etc… so we find it more productive to offer email/forum support only so we can allocate and plan time dedicated for this. I know it’s abit annoying but hopefully soon we can offer a dedicated support line as we get bigger :slight_smile:

Many thanks Alex!

I’ll shoe horn the caps in. They’ll be a tight fit. I’m kinda of a belt and braces guy and like to over-engineer the stuff I build. It’s always preferable to try and nip the interference at it’s source, rather than to try and filter it out further down the line. Voltage spikes propogating back and frying the VTX case in point :slight_smile: -)

As an aside, I’m not entirely certain that an electrolytic cap (by itself) may entirely absorb all the HF rubbish generated. But it’d go some way to taming it… wonder why they don’t put them in? Perhaps it’s a cost thing…

Re: phone support. Ok - I didn’t realise there was just two of you. In which case, I completely understand! I hope unmannedtech grows big!

All the very best, Chris.