2.6 Controller Board : Max Current Supported to Motor?


#1

I am interested in adding these new waterproof thrusters however I don't know the max current limit the board supports.

http://www.bluerobotics.com/store/thrusters/t200-thruster/

There are two models with ESC that max at 11A (10lb trust) vs 25A (10lb thrust).


#2

(Disclaimer: I'm a software guy talking electronics!)

The board does not have any explicit current limit to the ESCs. It's more a function of how much current the Batteries can source. For reference, the model of the OpenROV kit that ships right now uses 18A ESCs.

-Brian


#3

Well, while Brian is correct in that the controller board doesn't have any current limit mechanism, there are definitely things on it which will melt if you draw too much current.

The main power switch to the motors (Q3) is a Si4425 mosfet that is rated for 20A of continuous load. I think you're probably OK with three of the T100 thrusters if you run them off of LiFePO4 batteries at 9.6V or so- they will draw less current at that voltage. T200 thrusters are not going to work at all. The next revision of the Controller Board will support a little more power, but it's still not enough for an ROV that uses the T200 thrusters.

What you can do, of course, is design an alternative battery buss that diverts ESC power around the Controller Board. Just make sure your batteries can support the higher current as well.

If you do decide to go that route, please post your design ideas so that others can see what you're doing too.

-W