Now, if i plug in more than 4 digital pins the relay starts to click (its losing connection) Seems like not enough power to energise the coils? I am within the current rating of the digital pin outs as far as i can tell, and this happens after 30 seconds or less (sometimes just a few seconds)
If i leave 4 and only 4 of the relays it'll work depending on load, if the fans are going this becomes intermittent though. i have heating pads, LEDs and CFLs and many fans. I have even tried adding a new 4 channel relay board but the same issue (coils click losing connection )happens as soon as i connect the pins from arduino uno to relay
Symptoms indicate, to me, a power problem. Please post a schematic of your wiring and photos that clearly show where all the wires go. Post the specifications of all the power supplies.
I have followed dlloyd schematic here (i hope its ok, i'm not sure how to draw them up) 8-channel relay board code - #5 by aarg
The jd-vcc 5V supply is coming from a breadboard psu https://www.diyelectronics.co.za/store/prototyping/37-breadboard-power-supply.html?search_query=psu+breadboard&results=4 which is being supplied 12v 4amp adapter
The arduino uno is being powered by a 9v 2amp adapter
And realising the power requirements of the breadboard psu now, i swapped the adapters around (now running 9v instead of 12v) and i went from 4 digital pins to 6 being able to be plugged in without malfunction
I'm sorry, i've answered my own question here. The easiest option here would be to get a 6.5/7v adapter, annoyingly i bought the 9v only today
