
Two-channel Grove relay module with SPDT contacts, controlled by a 5 V GPIO signal. Switches up to 250 V AC or 110 V DC per channel; connects via standard 4-pin Grove cable.

Grove control-side supply for the relay module; Seeed lists operating voltage as 5V
Grove control-side ground/common reference
Digital input controlling relay K1; Seeed states SIG1 high turns Q1 on, energising K1 so COM1 connects to NO1
Digital input controlling the second relay channel; Seeed lists the module input interface as Digital SIG1/SIG2
Common terminal for relay channel 1; default connects to NC1, energised relay connects COM1 to NO1
Normally-closed terminal for relay channel 1; connected to COM1 when K1 is not energised
Normally-open terminal for relay channel 1; connected to COM1 when K1 is energised
Common terminal for relay channel 2, matching the second SPDT relay output channel
Normally-closed terminal for relay channel 2, matching the second SPDT relay output channel
Normally-open terminal for relay channel 2, matching the second SPDT relay output channel
| Pin | Type | Function | Voltage |
|---|---|---|---|
| VCC | Power | Grove control-side supply for the relay module; Seeed lists operating voltage as 5V | 5V |
| GND | Ground | Grove control-side ground/common reference | 0V |
| SIG1 | GPIO | Digital input controlling relay K1; Seeed states SIG1 high turns Q1 on, energising K1 so COM1 connects to NO1 | 5V logic per Seeed relay schematic explanation |
| SIG2 | GPIO | Digital input controlling the second relay channel; Seeed lists the module input interface as Digital SIG1/SIG2 | 5V logic per module operating voltage |
| COM1 | Unknown | Common terminal for relay channel 1; default connects to NC1, energised relay connects COM1 to NO1 | load side, Seeed rating up to 10A 250VAC / 10A 30VDC |
| NC1 | Unknown | Normally-closed terminal for relay channel 1; connected to COM1 when K1 is not energised | load side, Seeed rating up to 10A 250VAC / 10A 30VDC |
| NO1 | Unknown | Normally-open terminal for relay channel 1; connected to COM1 when K1 is energised | load side, Seeed rating up to 10A 250VAC / 10A 30VDC |
| COM2 | Unknown | Common terminal for relay channel 2, matching the second SPDT relay output channel | load side, Seeed rating up to 10A 250VAC / 10A 30VDC |
| NC2 | Unknown | Normally-closed terminal for relay channel 2, matching the second SPDT relay output channel | load side, Seeed rating up to 10A 250VAC / 10A 30VDC |
| NO2 | Unknown | Normally-open terminal for relay channel 2, matching the second SPDT relay output channel | load side, Seeed rating up to 10A 250VAC / 10A 30VDC |
Grove control-side supply for the relay module; Seeed lists operating voltage as 5V
Grove control-side ground/common reference
Digital input controlling relay K1; Seeed states SIG1 high turns Q1 on, energising K1 so COM1 connects to NO1
Digital input controlling the second relay channel; Seeed lists the module input interface as Digital SIG1/SIG2
Common terminal for relay channel 1; default connects to NC1, energised relay connects COM1 to NO1
Normally-closed terminal for relay channel 1; connected to COM1 when K1 is not energised
Normally-open terminal for relay channel 1; connected to COM1 when K1 is energised
Common terminal for relay channel 2, matching the second SPDT relay output channel
Normally-closed terminal for relay channel 2, matching the second SPDT relay output channel
Normally-open terminal for relay channel 2, matching the second SPDT relay output channel
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