Hi
I use alot of the mk138 thermostats.
I use a 1 amp dc adapter to power the thermostat along with a 10 watt halogen bulb sharing the power supply. This should use around 900ma.
I’ve been finding that when the relay clicks over, rather than making a clean click some of them make more of a crunching sound.
When I don’t use the bulb or use an adapter with more amp rating (3 amp) they never do it.
Any idea of why this might happen as really the adapters I use should be powerful enough to work with the bulb and thermostat, is there a solution without using a more expensive psu.
Thanks, I ask alot of questions about these mini kits and always appreciate the quick informative reply.
Probably, the adaptor voltage drops at turn on or there is too much ripple.
Using a more powerful adaptor can help.