RevPi Connect+ relay not working properly

albertobueno · Post by **albertobueno** » 10 Jan 2024, 13:22

Hi,

I have been trying to use the on-board relay of the RevPi Connect+ to open the circuit of an emergency stop chain. When I activate the RevPiLED bit 6 I can hear the relay Latching. The problem is that I get always continuity between the relay terminals. It doesn't matter if the bit is on or off. I opened the RevPi and I measure the voltage across pin 1 and 12 of the EE2-5NU relay and I have 0 V even it the bit is True.

What I think it is happening is that the relay is just being activated by a Pulse and not a constant 5 V. Is that the normal operation? How can I get the relay to stay in the energized position?

Best regards

Post by **dirk** » 10 Jan 2024, 14:11

Hi albertobueno, the relay is in the normally closed state. I have taken the information from the RevPi Connect circuit diagram, see here:
https://revolutionpi.com/tutorials/down ... haltplaene

: Relay; msedge_5ZdBhMCNgZ.png (24.38 KiB) Viewed 15781 times

I can't imagine what you describe, that it appears that there is only one pulse because it is a mundane relay.
Here is the tutorial for the relay, and it should be possible to open and close the contact:
https://revolutionpi.com/tutorials/uebe ... kt-connect

The states are also shown here in the tutorial on the status bytes 0=Relay closed 1=Relay open

: Status Bytes

The relay may be defective. This is because it is a mechanical component that wears out due to the number of switching operations.
I had the experience myself once and switched the relay on and off on the RevPi Connect in an endurance test over the weekend.
When I examined the test results on Monday, I noticed that the relay was no longer working.

albertobueno · Post by **albertobueno** » 15 Jan 2024, 17:57

Hi Dirk,

Thanks for the reply. I am 100% the relay is working and I have already connected an oscilloscope to the relay coil and it receives a 5 V pulse when the bit is activated. I guess there is something in the software/hardware besides the relay that is malfunctioning. I haven't updated the Connect+ since around 2020.

Form the moment I am using a DO from another module.

Best regards

Post by **dirk** » 18 Jan 2024, 15:27

Hi albertobueno, So it seems strange to me and my recommendation is that you update your system that has not been updated since 2020 using the following checklist created with great attention to detail:
https://kunbus-gmbh.atlassian.net/servi ... /836468748

albertobueno · Post by **albertobueno** » 19 Jan 2024, 15:35

Hi Dirk,

Yes, updating the image to the latest resolved the issue.

Thanks!

Post by **dirk** » 26 Jan 2024, 09:09

Hi albertobueno, thank you very much for your positive feedback.