I searched but I couldn’t find anything on the voltage of the new controller. We were driving in high gear on a low battery yesterday, and the radio link was fading in and out. The one thing I noticed, though, was the controller never reset at such low voltages. So did FIRST lower the minimium voltage, or will we still lose controllers.
PS: I saw the battery voltage down to 5.7v
In the IFI RC Ref Guide it says:
The +12V and GND connectors on the Robot Controller are intended to accept power from a +12V
battery. The current draw for the Robot Controller is typically between 0.75A to 1.5A. The maximum
voltage allowable is +15.0V. Exceeding the +15.0V limit may damage internal voltage regulators and
will void the warranty. The minimum required voltage is +8.0V.
So I’m assuming at below 8.0V the RC should reset and require a reset to turn on again…like in previous years.
It didn’t need it, but I think they could have wired it in with the auto-reset of the robot when you download the code
Well, if the controller automatically resets itself when it gets power, losing the controller shouldn’t totally kill the robot (like what happened to us at the Midwest regional last year)
*Originally posted by Ricky Q. *
So I’m assuming at below 8.0V the RC should reset and require a reset to turn on again…like in previous years. **
Below 8V, the RC will just shut down. Because of the shutdown, the light will turn off, thus reducing current draw out of the battery. This, in turn, means there will be enough juice to power the RC again. Unfortunately, this also means the light will turn back on, causing the voltage to drop again and the whole cycle to repeat itself. You shouldn’t need to press the reset button unless it comes up with a basic run or basic init error.
The controller will reset below 8 volts if the low voltage continues for a length of time. This time seems to have improved over last year’s controller. I would guess that Innovation First added or beefed up the power supply capacitor to hold up the controller during power sag. You gotta love those Innovation First guys for listening to their customers. However, if you are seeing voltage dropping below 8 volts (you do know how to set the OI to read robot power?) then assume the controller is going to reset and take some appropriate action. RC reset/initialize is a couple of seconds of no play.