Robot loosing comms to major voltage drops

We were driving, and our robot suddenly lost comms. Looking at driver station, voltage dropped to like 7. We went to web dash and noticed that when turning, the drive base drew 13A on one side but I think thats normal right? What should we do next to check?

One property of the batteries we use in FRC is that they can degrade over time and show a good “float” voltage (ie not loaded) but severely drop when current is drawn (using motors, etc.)

If you have a battery beak, it’ll show the “health” of the battery by synthetically loading the battery, but isn’t going to be a full FRC robot. Therefore if the battery beak shows absurd voltage drops under relatively low induced currents, your battery is probably toast.

This must be a new battery given that you’re a rookie, but I hope you have more than one…

No this is a battery we’ve used throughout this season. First time this happened. It also happened across two different batteries so I don’t think the batteries are toasted.

Check out the Driver Station Log to see the battery voltage graph from when it began to dip.
You can compare your recent robot performance with any time in the past to see if things have changed a lot or not.
In this example log the yellow plot is the robot battery voltage.

You should also double check all of your power wiring (especially the wires between the battery and PDP) to make sure everything is tight. If you can wiggle it, it’s too loose. Loose connections in the main power wiring increase resistance there, which can lead to high voltage losses from normal current draws.

Thanks guys but figured out. Battery just not charged enuff

For future reference, there’s a good list of troubleshooting steps here: