Hi All,
I need a little help designing a basic light sensing relay to turn on and off a welding fume extractor whilst welding.
I believe a fast acting photo diode, controlling a simple timer relay is probable the best approach.
The fan has a 5KW - 3 phase contactor to run it with a 24v dc coil, so ideally I would like to use that 24v dc supply to also power the photodiode circuit. ( if that's easy, otherwise I can put in a second power supply to suit )
I am fine with the ac side of things and an off delay relay to allow the fan to run on for a while after the welding stops, but need a little help with the dc side.
Can any of you electrical Wizards suggest a little circuit that would detect the light from the welding torch and engage a small timer relay to power the 24v dc starter ? ( possibly with a some form of sensitivity adjustment, so I can prevent it false triggering in sunlight. )
I need a little help designing a basic light sensing relay to turn on and off a welding fume extractor whilst welding.
I believe a fast acting photo diode, controlling a simple timer relay is probable the best approach.
The fan has a 5KW - 3 phase contactor to run it with a 24v dc coil, so ideally I would like to use that 24v dc supply to also power the photodiode circuit. ( if that's easy, otherwise I can put in a second power supply to suit )
I am fine with the ac side of things and an off delay relay to allow the fan to run on for a while after the welding stops, but need a little help with the dc side.
Can any of you electrical Wizards suggest a little circuit that would detect the light from the welding torch and engage a small timer relay to power the 24v dc starter ? ( possibly with a some form of sensitivity adjustment, so I can prevent it false triggering in sunlight. )