I love the idea of using a 5v micro controller to control my 110v 10 amp outlets. My only concern is the high voltage frying my board and burning my house down. Any thoughts?
Hi Zachary, Without knowing your experience level I would definitely approach this with caution and the fact that you ask the question indicates that this might not be a good idea. The board you show has relays rated at 10 amps but they are very marginal for switching house lines. What is to keep someone from plugging in a hair dryer or a space heater? The design of the board also brings the switch main lines into close proximity. Here in the USA mains are split off a power feed with 110 volts on either side of a neutral. This means that the 110 lines are out of phase with each other and actually represent a voltage of 220 volts across them. Unless you are careful you could easily have 220 volts on the relay board separated by a very small distance and held by a header that isn't designed for this purpose. The board looks like it would be fun to experiment with but the voltages that are appropriate would best be under 50 volts and isolated from the mains. If I had to use this board for this purpose I would put individual 24 volt contactor relays on each outlet line in proper code enclosures and use the relay shield to switch the 24 volts needed to drive the contactors. This would be safe and you could increase the current handling above the level of the circuit breakers on the individual lines.
Hi Zachary, Without knowing your experience level I would definitely approach this with caution and the fact that you ask the question indicates that this might not be a good idea. The board you show has relays rated at 10 amps but they are very marginal for switching house lines. What is to keep someone from plugging in a hair dryer or a space heater? The design of the board also brings the switch main lines into close proximity. Here in the USA mains are split off a power feed with 110 volts on either side of a neutral. This means that the 110 lines are out of phase with each other and actually represent a voltage of 220 volts across them. Unless you are careful you could easily have 220 volts on the relay board separated by a very small distance and held by a header that isn't designed for this purpose. The board looks like it would be fun to experiment with but the voltages that are appropriate would best be under 50 volts and isolated from the mains. If I had to use this board for this purpose I would put individual 24 volt contactor relays on each outlet line in proper code enclosures and use the relay shield to switch the 24 volts needed to drive the contactors. This would be safe and you could increase the current handling above the level of the circuit breakers on the individual lines.
If I had to use this board for this purpose I would put individual 24 volt contactor relays on each outlet line in proper code enclosures and use the relay shield to switch the 24 volts needed to drive the contactors.
Fully agree! This is how I ALWAYS approach interface with mains electricity. I would highly recommend keeping the relay interface card in a separate enclosure and running 24V cables into your contractor housings.
This drastically reduces the chances of a stray mains wire from making contact with your arduino/touchscreen/fingers.
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