Can I connect two of those relays safely?

[Tormek]

Hello!

I want to connect two 8 channel relays (https://tomtop_game.guphotos.com/i/w?u=/images/H/H9449/H9449-4-6a30.jpg) safely to my pi 3. Each one requires about 160mA on 5V. 5V takes the power directly from the supply so should be no problem, there are two 5V pins but I saw this 16 channel relay (https://s3-ap-southeast-1.amazonaws.com ... e1595f.jpg) and it requires 12V power supply, it makes me have doubts about the safety.

So, can I connect two of those relays safely to one Pi board?


EDIT: https://www.ghielectronics.com/download ... elayX1.pdf
This one is SRD-05VDC-SL-C

[RDS]

I have bought the 2 channel version of these boards.
The problem as I see it though is that the GPIO pins of the RPi that I wanted to use as outputs only operate on 3.3v.
I have some of the same form factor relays that are 3v and I thought about changing the relays for my 3v versions.
The 2 channel version when only used with 1 relay takes about 55mA at 5v. However, the opto isolator only takes 1.4mA, so I am currently looking at splitting the Power Supply requirements so that the Pi only sees the 1.4mA required by the Opto Isolator part of the circuit.

(Incidentally, have you any idea what the 'jumper' is for, shown top right of the picture in your first link, because I have the same situation on mine)

[gordon77]

Regards the link take alook here where you'll find a wiring diagram...

https://www.sainsmart.com/8-channel-dc- ... logic.html

The link allows you to seperate the relay supplies. It looks like 2-3 connects Vcc to the relays.

DON'T connect 1-2, as it looks like it will short Vcc to gnd.

Remove the link and connect an external 5v supply to pin 3 (5v for JD-VCC) and 1 (gnd) to power the relays.

[RDS]

@gordon77
Thank you very much. I had tried to find a wiring diagram for my product without success.
(I can confirm that a short would occur if the jumper is moved across)