how to wire to relay

Printed From: the12volt.com
Forum Name: Relays
Forum Discription: Relay Diagrams, SPDT Relays, SPST Relays, DPDT Relays, Latching Relays, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=132762
Printed Date: May 06, 2025 at 9:38 PM

Topic: how to wire to relay

Posted By: jsxmike
Subject: how to wire to relay
Date Posted: November 23, 2012 at 6:40 PM

I am trying to connect a Raspberry PI to a relay to control a 12V output.

I have a OMRON G5LA-1 relay.

This is a 5 pin relay. each corner has a pin and one end has a pin in the middle.

The vendor diagram shows them PINS 1-5.

The output driver needs to supply 12V constant output and have a short ground pulse returning back to 12V constant.

I found this diagram for a pulse output: posted_image

Can someone let me know what pins to connect to what?

This is the instructions from the Raspberry PI site that shows good informatin - except what pins to connec to what from the relay:

https://www.susa.net/wordpress/2012/06/raspberry-pi-relay-using-gpio/

posted_image

Replies:

Posted By: kreg357
Date Posted: November 23, 2012 at 7:43 PM

Here is a link to the OMRON Relay spec sheet : https://components.omron.com/components/web/PDFLIB.nsf/0/4F7D9D9CA026C97E862573930070AC4F/$file/G5LA_E_0911.pdf

The way they have them numbered, looks like pins 2 and 5 are the relays coil.

Relay Pin 2 to Raspberry +5V
Relay Pin 5 to Q1 collector
Relay Pin 3 to AC1
Relay Pin 1 to Motor
Relay Pin 4 not used - insulate

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Soldering is fun!

Posted By: jsxmike
Date Posted: November 23, 2012 at 7:55 PM

Thank you very much.

Posted By: jsxmike
Date Posted: November 23, 2012 at 8:53 PM

I have drawn up what I think is the right way to merge the two diagrams (inputs and outputs) -- to have the output drive a sustaining 12V until the relay is pulsed, then it will drive GND and revert back to the 12V.

The Raspberry PI is trying to control a driveway gate motor for remote control to activate the gate to open or close. The INPUT line on the Gate Sensor will activate the motor when it detects a GROUND pulse input.

posted_image

Is this right?

Thank you

Posted By: howie ll
Date Posted: November 24, 2012 at 1:21 AM

Your last diagram is correct.
That Omron unit is the standard SPCO format for PCB relays.

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