This is another board to be used in connection with a parallel port of a pc or using a microcontroller. It is a simple board-driver for 8 relays. The board is protected by optocouplers and it uses standard, very common, relays (G5LE - 10A - 220V).
It has the same schematics of the three relays board (available for downloading in the repository) for a cnc machine except for the driver (ULN2803). Very simple and efficient.
The position of the optocouplers allows the use of 8 PC817 or 4 PC827. The power supply is strictly connected with the relays, therefore if 12V relays are used the board must be powered at 12V, otherwise 5V.
TO BE CAREFUL - HIGH VOLTAGE INVOLVED
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8 relays | 3 relays |