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Relay module to db9 wiring - Printable Version

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Relay module to db9 wiring - Rayzzfish - 10-16-2020

[attachment=440][attachment=441]I've been having trouble with wiring the 8 relay module to the db9. Any help would be great. I will attach a couple photos to show what I'm working with. Thanks...


RE: Relay module to db9 wiring - Rob F - 10-16-2020

(10-16-2020, 11:27 AM)Rayzzfish Wrote: I've been having trouble with wiring the 8 relay module to the db9. Any help would be great. I will attach a couple photos to show what I'm working with. Thanks...

Is that plugging into the controller, as in is it male?

The only pin that really matters is Ground and VCC. The signal pins can be sorted out in reef-pi.

On the right side of image you can see the pin out. There's so many different standards I don't really trust pin numbers anymore so use your continuity meter and touch what I have marked as Ground pin and see which screw terminal it goes to, then add the ground wire to that screw terminal.

I'm guessing the screw terminal marked "GND" goes to the outer casing of DB9, verify if it does. If so you can use that for +5v or +12v to power up the relay module. However on the controller board behind power bar 1 DB9 you'll need to solder a pad to send +5v or +12v.

[attachment=442]


RE: Relay module to db9 wiring - Rayzzfish - 10-17-2020

(10-16-2020, 12:30 PM)Rob F Wrote:
(10-16-2020, 11:27 AM)Rayzzfish Wrote: I've been having trouble with wiring the 8 relay module to the db9. Any help would be great. I will attach a couple photos to show what I'm working with. Thanks...

Is that plugging into the controller, as in is it male?

The only pin that really matters is Ground and VCC. The signal pins can be sorted out in reef-pi.

On the right side of image you can see the pin out. There's so many different standards I don't really trust pin numbers anymore so use your continuity meter and touch what I have marked as Ground pin and see which screw terminal it goes to, then add the ground wire to that screw terminal.

I'm guessing the screw terminal marked "GND" goes to the outer casing of DB9, verify if it does. If so you can use that for +5v or +12v to power up the relay module. However on the controller board behind power bar 1 DB9 you'll need to solder a pad to send +5v or +12v.

Okay I got everything so far. As ground goes to 5 pin, and vcc goes on the ground connection of the db9. So now the question is what pad and where would I get the +5v or +12v. Thanks Rob for the help. I think my second power bar I will order one. This weekend makes it a little easier...


RE: Relay module to db9 wiring - Rob F - 10-17-2020

No problem, glad you got it. I think your board has the solder pad but it might not, here's where it would be.

[attachment=443]

If you don't have it you can solder a wire from the +5v or +12v points I marked out to the DB9 housing.

2nd power bar would be easier but I have some if you need.


RE: Relay module to db9 wiring - Rayzzfish - 10-17-2020

(10-17-2020, 09:23 AM)Rob F Wrote: No problem, glad you got it. I think your board has the solder pad but it might not, here's where it would be.



If you don't have it you can solder a wire from the +5v or +12v points I marked out to the DB9 housing.

2nd power bar would be easier but I have some if you need.
Thanks for the help Rob. I order my second one today...


RE: Relay module to db9 wiring - Rob F - 10-17-2020

(10-17-2020, 11:11 AM)Rayzzfish Wrote:
(10-17-2020, 09:23 AM)Rob F Wrote: No problem, glad you got it. I think your board has the solder pad but it might not, here's where it would be.



If you don't have it you can solder a wire from the +5v or +12v points I marked out to the DB9 housing.

2nd power bar would be easier but I have some if you need.
Thanks for the help Rob. I order my second one today...

Thanks, I appreciate it! I'll get it out on Monday and email you a tracking number.