Can you tell us which esc you are talking about?

Fair enough Brian but please understand that without knowing exactly what we are talking about you can't really expect us to provide the comments that you have asked for.

Paul

i disagree brian

electronize which are sold as boat esc are not waterproof

microgyros esc also sold in heat shrink type sleeve open at both ends not waterproof

microgyros were on sale at waarwick boat show lots were sold

also ive been told that if you seal the ends they will pack up as heat needs to escape how true this is

i dont now ive used many many differant esc and dont think ive ever come across one thatss

100% waterproof even mtroniks are not 100% ie submersable as water gets in around the set button splash proof yes

hope this helps

Hello Brian

I have used an alloy clad waterproof esc with great effect by mounting the unit on the outside of the hull so I agree that the term 'waterproof' is very important, I have also done what you have done by sealing a plastic clad unit with silicon (and failed) I can't comment on your unit only to agree with what Neil has said about changes.

With this forum you have access to some of the best model boat builders and also the best advice available but without knowing which esc you are talking about we can only speculate on your problem.

Paul

Ashley

As usual you have injected a note of caution.

But the question still remains that without chucking it in the wet stuff how else would you water cool a esc?

Paul

Brian

I think in all fairness that you are over-reacting a touch ref the water-proof requirements of model boat electronics. You are, after all, intending the model to float and to run with the water on the outside of the hull! If a speed controller has water-cooling pipes then make sure that the flexible pipes you use to connect them to the scoop and outlet are a good tight fit. Also ensure there is a decent coaming all round the radio access "hole" in the deck, and don't mount anything electrical directly onto the bottom of the hull. It's only common sense.

If you are really intent on having fully waterproofed ESCs, servos and receivers then you are going to have a hard time buying equipment. None of our ESCs are waterproof and yet I can't recall having to fix any with water-damage, save those which had been fully submerged when the model sank (and that's maybe half a dozen in five years). Trust me – if you really feel that you need that level of protection then you've clearly little confidence in your building ability.

As regards speed controllers sold with ridiculous claims for continuous current rating (e.g. 150Amps), my only comment would be that sometimes you don't get what you pay for. Buy cheap = buy twice. Silicone? If I had a speed controller sent back which was slathered in this crud then I wouldn’t be able to work on it – warranty or not – so please don't do it.

Dave M

Edited By Dave Milbourn on 29/05/2012 18:44:23

I've always taken the line that unless you are going for ultimate speed regardless then the need for any sort of cooling is an indication of inefficiency in the setup. Heat is simply wasted battery power that would be better employed in driving the boat through the water.

Colin

One of the problems of running electric motors on my models is weight.

As most of you know my models tend to be on the large size and so need quite a bit of power to move them and even at moderate speeds the esc's do build up some heat, I have tried fans and ducting to move cooling air through the hulls with only moderate success so water cooling does have its attractions.

Paul

Dave

A serious question from me (for once)

As you know my knowledge of electronics is stuck back in the 70s and my basic rule of speed control is having a fist full of throttle and enough water to avoid the bank so when it comes to esc's I tend to blow them up.

I don't understand how the esc shown below can be water cooled without chucking it in the drink.

It is listed as a water cooled 60amp Boat ESC

Paul

Hi Trevor

Is it as easy as that?

Can such a small area keep the esc cool.

Paul

Paul

It depends on several factors:

The difference in temperature between the water and the power FETs;
The rate at which the water flows through the tubes;
The area of contact between the FETs and the water tubes/pad.

Frankly I can't believe that such a minimal effort as this to provide cooling in a (supposedly) 60A ESC would equate to a decent-sized and adequately finned aluminium heat-sink, but I guess the proof of the pudding etc etc. The very best solution would be a physical heat-sink which itself is water-cooled. See Fig #8 here **LINK**

Dave M