We have had several reports from our engineers noting RCBOs protecting lighting circuits running at a significantly higher temperature than the rest of the DB or amibient.

One example from today from is a lighting RCBO running at 43 degrees where the ambiet temperature in the riser is 20 degrees.

The engineer has opened the DB up and there is nothing obviously wrong and all terminals are tight.

We've noticed the same thing several times recently and it always seems to be lighting circuits.