Is it possible to run two CIM motors to one motor controller?
Yes, it’s possible, but it’s not recommended and not legal for competition under the 2014 robot rules. Use one controller per motor if you can.
OK thanks, this isn’t for a competition it is for a t-shirt cannon for our school. Is there a possibility the controllers were burn out?
Let me put it this way: CIMs can pull an awful lot of current. Let’s assume that you run 40A per motor, which (can be) low, so 80A for the pair, and send that through your motor controller (Talon, Jag, or Victor). Note that it’ll take a bit for your circuit’s snap-action breaker to trip, and it’ll untrip as soon as it cools off a bit. (Or, you’ll end up with a case where the CIMs are not performing like CIMs due to only getting 1/2 the current they’d like.)
If you get into a situation where those motors are having to work hard, you’re probably going to be buying another speed controller anyways, to replace the one you fried.
That said: Talons, Jaguars, and Victors are not the only speed controllers out there. Some of them might be a bit cheaper; some a bit more expensive. It might be a good idea to do a little research. (Trying to remember a couple of brands I’ve been known to see used in a project–one will safety itself off and refuse to turn back on, one will not.)
Is there a particular reason that you want to run two CIMs off of one speed controller?
Does this mean you’ve already tried this? Yes, speed controllers can burn out if you pull too much current and an extra CIM motor will double* the current draw. Jaguars are the most susceptible to this, but Victors and Talons have their limits as well.
*Not exactly the case if the motors are connected in a gearbox under load, but the current does increase significantly.
For the FRC approved motor controllers, it is quite possible to burn them out by running two CIMs through one. However, if you use one rated to handle the current draw of two CIMs, you will be fine (as far as the speed controllers are concerned, you may have issues with other electronic components).
We have run 2 cim motors on a single Talon WITH Fan and had no issue. I wouldn’t recommend it, but it will work. I think you’d be better off forking out the money for another controller and just using a Y cable rather than potentially nuking one.
You can run the motors in series on one controller if you don’t need the speed.