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[funtimefrankie]

Are there any down sides in fitting a higher rated ESC than the motor...

ie a 25amp running a motor that would never draw more than say 10 amps.

[FullLeatherJacket]

Only if you intend to go out and buy one; then it's called a waste of money! Technically, the answer to your question is no. OK?
FLJ

[Martin (Admin)]

 It used to be, the closer the amperage match to the motor, the better the slow speed control,
 but with these new fangled electronical-a-mebobbies it doesn't seem to matter.

[HS93 (RIP)]

Getting a higher rated speed controller can be useful as a higher rated one will go with most boats and motors but a small one can only be used with small motors as there is not a big difference in price i would always go for the higher rated if it only a small difference then I have flexibility for the future to swap about,

    also be aware of Chinese amps they are not the same as UK amps they can be much smaller

Peter

[funtimefrankie]

Thanks for the replies, It's one I already have so the cost isn't a factor, It was the slow running I was wondering about.

[DickyD]

    also be aware of Chinese amps they are not the same as UK amps they can be much smaller

Peter

Are you allowed to say that on here Peter ?

[HS93 (RIP)]

Are you allowed to say that on here Peter ?

    if I put what I was going to put and wanted to put  I would now be banned   


Peter

[malcolmfrary]

Some manufacturers have an optimistic view of the power handling of their creations.  They may be suffering from poor quality control, it could be that the specifications that are published omit the odd pointer, like the need for a liquid nitrogen cooling flow or similar.
Nowadays, any ESC that will handle a large motor will also handled a small one, provided that the motor can handle the voltage from the battery.  Some ESCs have better low speed handling than others, but this applies to whatever size of motor they are working with.

[wombat]

I suspect what happens is that the ESC, especially the mega-cheap ones with the ihgh numbers are rated on what the manufacturer's datasheet says the output transistors can cope with, without considering all the riders that the manufacturers put on them - like duration or size of heatsink.

The reality is much lower - for example the P98 is rated at 30A with the huge heatsinks fitted - the headline figures for the FET are 48A continuous, 144A peak - however to achieve 48A continuous through it you have to increase the heatsinking by at least 100% or water cooling the thing and ignoring the manufacturers recommendations. You can achieve the 140A peak - but do it for more than a small fraction of a second and the unit will be toast.  Rule of thumb - if you cannot touch the heatsink, you need more cooling.

If you see an ESC that rates tiself at 100A or even 50A and it is the size of a postage stamp, tread carefully.

Always fuse the ESC conservatively - absolute minimum value you can get away with - always rate the ESC higher than the motor fuse. Always watch the ESC temperature - no use getting the ESC so it runs OK but gets so hot it melts or burns through the bottom of the boat. SMART fets and trips help to prevent problems but the best policy is to have the thing setup so they are a last ditch protection not a routine one

Wom