If we are talking about drill motors, i.e. 12-18V cordless drill motors, they pull a lot more than 8 amps. I am not speaking from data sheets here, I am talking from my actual set-up. My motors draw around 8 amps with the wheels in the air, spinning freely. At start-up, they can draw 15 to 20. If you were to actually stall a motor (this is not easy to do) you can actually reach 80 or 100 amps. Seriously. If using drills, I would not use anything smaller than a 20amp x 2 controller. Bigger the better. Also, a fuse is manditory. I run a 40 amp “slow-blo” fuse and it has saved me many times.
When used in a drill, they usually use a clutch so they never really stall. If there is no clutch or set to “drill mode”, the user normally lets off the trigger when the thing stops spinning. If one were to continue to stall the motor, it does pull upwards of 50 or 60 amps --all the way up to 100 or more (depending on the drill) and either a thermal shut-down happens or an internal, self-resetable fuse kicks in.
Look, all I am saying is that I have melted traces on the PCB and “welded” my relays shut. Easy solution is A) don’t let them stall and B) use a fuse, period.
I am sure it won’t handle 110 A as said, but maybe it could handle the current of the drill motors? I just realize that it would be nescessary to buy 2 of them, 1 for each motor, and it means it will be more expensive than designing oneself…
I have some old drill motors (but useless because without gearbox) and I have tried to measure the current, but it seems my multimeter don’t work in amp mode (maybe the fuse) but I powered it with an old PC alimentation:
It works on the 5V channel, wich is limited to 16A, but in doesn’t works (my alimentation power down for saving itself) on the 12V channel, wich is limited to 7A. So I guess it use between 7 and 16 Amps, wich is quite big for no efforts current! with the gearbox it will be more, and with 2kgs of robot to move it will be much more ^^
And by the way, I have a good news! I succesfull installed jmyron, controlp5 etc… and I am testing TheBox’s sketches and trying to adapt them to my robot (we don’t have the same way to send orders) and I will give you a feedback soon.
Yes I understand now, I am searching for a termical or electromecanical security shutdown, and I think I won’t remove the cluch (is this what I think it is, some mecanical part who limit the torque?), and use weaker drills than you: I just need to move a small robot.
