ELEGOO Relay Module 4 Channel

Very neat little piece of kit. I'm using this module interfaced with IR detectors for train detection on hidden model railway storage loops. The IR detectors have an output which goes low when an object is detected and this module requires an input which goes low to activate the relay, so they work together a treat, all running off 4.5 - 5V. Also comes with a tiny screwdriver for the terminals and a ribbon cable for connecting up - very useful! I can't comment on the life expectancy of the relays though.

Compact, easy to use, well laid out and fair value for money.

Like others the board is very good, but the relays have a tendancy to latch in a closed state if they have been energised for a period of time. I switched out the relays for OMRON G5LA-14-5VDC - you can't buy them here anymore as OMRON have discontinued them, but ebay has plenty of listings still from China (i used the seller smallpartsbigdifference) and they have been rock solid since.

This is a solidly built module, well constructed, great soldering and very nicely finished. I feel it inspiring enough to buy another when I need as, although I could make my own, it wouldn't be as good and would be for no real financial saving either. It's being used as a mute function within balanced line studio desk audio outs. Thank you.

Easy to control and does exactly what I wanted it to do - control a 12v pump and double water/Solenoid Valve for an irrigation system

Nice that it comes with a screwdriver

I have both the 4 and 8 relay boards from elegoo and although they both look very similar as far as component layout, the 8 channel board has become unreliable after only a few weeks of use.

Beware that there is no documentation, and the relays operate when their associated control pin is driven to ground, not when it is driven high. I didn't realise this at first and assumed the unit was faulty. It isn't. Its a good system because it draws very little current from the associated microcontroller.