ESC efficiency and Manufacturer differences

[ray schrauwen]

It might have been Terry Davis (if all fails blame him ) that mentioned some esc's can make a boat be faster than others.

I was curious as to which esc's seem to be better than others?

What makes it better, FET on resistance or something else?

Cap banks when done correctly can reduce ripple so does that add to efficiency?

I don't have any esc needs at this time however, like some others I'm a bit excited to hear Castle is trying another kick at our can.

[Prodrvr]

Just the other day, I was reading either here or somewhere else that someone got 10mph more from just changing the esc. Gonna see if I can find it.

[ray schrauwen]

They said that but I'm not sure if they said which esc it was. Please do!

[NativePaul]

When the swordfish first came out they'd very large throttles and produced several hundred RPM less than other ESCs mine quickly got relegated to the parts bin and at the time there was no PC link available for firmware updates to potentially fix it. I haven't bought one since to see if they have improved or not, in case I am wasting my money again.

There was a while when the Castle Ices were running very inefficiently, but the firmware fix was pretty quick to come out and Castle link makes the process easy.

Marcus ESCs have a very good reputation for efficiency, but I have not used one yet.

There are several things that make a good ESC, more MOSFETs, bigger MOSFETs, or better MOSFETs will all lower the resistance and give more efficiency, as will a better cooling solution, and a lighter ESC will let the boat run more efficiently, but the Castle example of going from an uncompetitive POS (for naviga style endurance racing), to one of the best ESCs available, with just software update proves that there is much more to it than that. The back EMF sensing and automatic timing algorithms are extremely important too.

[Prodrvr]

They said that but I'm not sure if they said which esc it was. Please do!

I can't find it.

[Fluid]

It clearly happens. Some ESCs have a high internal resistance, some a higher switching efficiency, and some a more accurate/appropriate timing adjustment. The latter may be the most important since timing is never fixed, it varies based on how well the ESC reads and meets the motor's demands.

I can't speak for the efficiency of different ESCs as my own experiences have not compared different makes in the same boats. I do know that current Castles are very efficient - throttling a P Hydro to 138+ mph means high efficiency.


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[Prodrvr]

And that's why I think I'll wait until the new Castle marine esc's come out for my next project.

[ray schrauwen]

Interesting stuff.

When I bought a Castle XL2, I have no idea what firmware it came with.

Haven't kept up with Castle since I've used most others until recently.

[Fluid]

I use 200 amp ICE Lites I bough years ago on closeout, so they aren't new. But I update the firmware regularly (most updates are for helicopters). It will be interesting to see what Castle comes up with for a new marine controller. Hope they have learned enough from their past experience.....and that they can base it on on existing platform to keep the cost down. But even if they don't do the latter, a reliable controller will be a good thing even if it isn't "cheap".




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[kfxguy]

I've seen differences in escs. Not much but a measurable amount. The well respected and like seaking 180 I thought was an efficient esc lost to an etti escs. I think by about 3mph. That was the fastest that boat had went at that time. The crappy driving manners of the etti forced me to go back to the seaking.

Something I've noticed:

I've noticed that even though I calibrate the throttle in some escs, it's still not full throttle your getting. What I'll do is (flex shaft disconnected) put the lowest voltage pack the esc will run and hold it wide open for a few seconds. Pull up the data log and note the rpm. Go up a couple percent on my throttle end point travel and repeat. Once you pass the true 100% max rpm your going to get, the rpm will go down. So then you go back. I've gained a couple thousand rpm from doing this on some escs. Attention to detail.

You can only do this on datalogging escs however.

[ray schrauwen]

Interesting indeed. Nice to know.