Average Current Draw

My team uses several robot test boards to test code on, and to practice wiring before the end of build draws near. Does anyone know how much current the robot electronics draw, on average? We are hoping to be able to just plug the test boards directly into the wall so that we can save on battery use. Obviously we need 12 Volts, but how many Amps does the board use?

Depending on what you have connected it can spike to hundreds of Amps however it appears for your uses if you keep it to just the Crio and possibly a CIM it should be under 50A (if the CIM is free spinning)

Are you asking about all electronics? I would guess that the Crio, Radio, camera, DSC, and several no load speed controllers will likely draw as much as 20 amps peak but typically much less. A typical ham power supply ought to do the trick. If you add the compressor or some motors, most power supplies will trip off on current overload.

I measured current for an idle control system last year at under 1 amp. Later that same season I learned that the main circuit breaker has a resistance that is very close to providing 1mV per ampere of current going through it. I briefly considered making a small circuit that would allow the main program to monitor its own current use. The team wasn’t interested, so I never pursued the legality of the simple wire connections. This wouldn’t prevent you from making measures of a running machine while it is not in actual competition to find out what current is being drained. I may make a symbiotic NXT robot with data-logging to ride along just for curiosity’s sake alone. If I knew more about arduinos I might be trying to use one of those to do it.

We won’t have anything connected to the board that will be drawing a lot of power. (motors, pneumatics, etc.), it will be just the control components.

Thanks for the posts, that helped a lot!

How much power does a CIM draw? At what voltage? Also if you know the weight of the motor and Jag/Spike/Talon that would be helpful for me to know.

That is the current for just a barebones Crio, right?

Slartibartfest, the stall current on a CIM is 131 amps at 12 volts.

Yes. I think there were four jags, but no motors running. No compressor and I don’t think the radio was powered either. The team was just leaving the board powered while they made programming changes and I wondered how long they could expect a battery to last. We develop a control board in parallel with mechanical fabrication. The current hungry parts are in the other room for most of the early fabrications.

A couple years ago we built an electrical board that hooks to a track on the ceiling I pull side to side. We put about 8 motors on speed controlers, 2 spikes 1 for compressor (not hooked up just for code visual) one for motor and a bunch of limit switches and the crio and PD and side car and a potentiometer. I hook up one battery and this usually will last me running motors and things for a week or more.