HiLetgo 12V 1 Channel Relay Module with Optocoupler Isolation

The module features a compact size of 50mm x 26mm x 18.5mm (L x W x H) and four fixed bolt holes (3.1mm diameter, 44.5mm x 20.5mm spacing). It includes a power indicator (green) and a relay status indicator (red).

The interface includes the following: Input: - VCC: Relay power supply + - GND: Relay power supply - - IN: Signal trigger input (selectable high or low level signal via jumper)

Output: - NO: Relay normally open - COM: Relay common pin - NC: Relay normally closed

The module is packaged with a 12V 1-channel relay module with an optocoupler isolation.

To provide an auto shut-down for Prusa i3 Mk2S, you can follow these steps: 1. Wire the module in parallel with the power switch. 2. Use the hotend fan power as the trigger. 3. When you start the printer and the hotend fan turns on (at around 50°C), you can turn off the power switch. 4. The printer will continue to run until the print is finished and the hotend cools down below 50°C. At that point, the relay will no longer be powered, and the printer will shut itself off.

The module uses a genuine, high-quality relay with a maximum load of AC 250V/10A or DC 30V/10A for the normally open interface. It employs an optocoupler chip for isolation, providing strong drive capability and stable performance. The trigger current is 5mA.

The module can be set to high or low trigger mode using a jumper. It has a fault-tolerant design, so even if the control line is broken, the relay will not move.

The interface design is user-friendly, with all connections available through direct terminal leads, making it very convenient to use.

product information: