Srd-05vdc-sl-c Fritzing -

A yellow wire connected Digital Pin 7 to the relay's trigger.

The SRD-05VDC-SL-C is a 5VDC relay module with a single-pole, double-throw (SPDT) configuration. It features a compact design, measuring just 23mm x 15mm x 10mm, making it ideal for space-constrained projects. This relay module can switch loads up to 10A at 250VAC or 30VDC, making it suitable for controlling a variety of devices, from lamps and motors to valves and solenoids. srd-05vdc-sl-c fritzing

If you design a custom PCB using the raw SRD-05VDC-SL-C (not the module) in Fritzing, you add a 1N4007 diode in parallel with the coil (cathode to +5V, anode to GND). Without it, Fritzing won't show the flaw, but your real-world Arduino will reset or fry. A yellow wire connected Digital Pin 7 to the relay's trigger

(like the 1N4007) to protect your controller from inductive spikes. Isolation: This relay module can switch loads up to

The raw relay has 5 pins: