blueroomelectronics
Well-Known Member
I'm assuming a low frequency square wave at lets say 40% duty ~ 75Hz would keep a small DC relay energized. Any problems with this approach?
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blueroomelectronics said:Why burn energy if you don't need to.
blueroomelectronics said:I'm assuming a low frequency square wave at lets say 40% duty ~ 75Hz would keep a small DC relay energized. Any problems with this approach?
blueroomelectronics said:I could double the frequency to 150Hz or 300Hz.
k7elp60 said:On a 12V relay and a load I checked the voltage drop across the closed contacts with a 25A DC load the voltage across the contacts was 86.7mV with the normal 12V on the coil. With the coil voltage reduced to 6V the voltage across the contacts was 88.6mV. I figgured this was due to the decrease in pressure created by the magnetic field.
Nigel Goodwin said:I still really fail to see why you're wanting to complicate things by driving the relays using PWM? - relays are designed to be permanently powered - the only reason would be to reduce current consumption, but if it's battery powered you wouldn't be using relays anyway?.