Shelly 2.5 overheating watts < 300

Hi,

I wonder if someone could help me work this one out. I have a shelly 2.5 set up as follows:

Channel 1 toggles 77w of lights.

Channel 2 toggles a night time motion sensitive flood sensor, taking 152 watts when triggered.

The odd thing I can't work out is that is, if channel 2 is on, but drawing no watts (e.g. it is day time so light has not been triggered) my shelly temp creeps up to overheating status.

But, If channel 1 is on and channel 2 is off entirely (as in relay switched off in shelly) everything remains operational.

This is the 2nd shelly I've tried in same location so don't think it's a defective unit.

Channel 2 is the final leg of 2 way switch, with Shelly switch going to common and output going straight to floodlight.

Also have one live into first channel L and then a short loop wire going from that L to second L.

Any thoughts welcome.

Thanks.

Thank you very much @66er! that makes sense.

I think I have just confirmed this by toggling the first of the two way switches and seeing the temperature start to drop swiftly.

This is will be a bit of conundrum on how to wire this. If my initial physical switch and second physical switch 'match', then them common will be live, sending 240v to my shelly to the switch port (in addition to the 240v going to L). If they don't 'match' that switch will have no voltage. Hmmmmm .Any ideas?

@66er Thank you, understood. I think I've figured it out though (in case anyone needs a tip who stumbles across this), one of the two traveller wires from the physical switch one will be live, and the other not, so combining those will give me an L i can use with my common going in the SW, forming a single 240v circuit.

Just tested and temps now down 60 when the both lights are 'on' but flood light not activated.

Appreciate the help thanks very much.