I discovered what appears to be a battery temperature monitor for the charger/inverters. I haven't been able to find any documentation on this device. As you can see the two connectors are disconnected and the eltrotlyte level light is illuminated. I have no idea how an electrical device can determine whether the electrolyte levels are high or low, assuming that's what this light means.

Does anyone have documentation on this device?
Temperature-Control.jpg

Thanks,