The Industrial Raspberry Pi Forum

Hi,
I am working on a project using a Revolution Pi Connect SE that uses the single output relay to control something.
We want this to be "safe", meaning if power is off to the Pi, or the Pi is on but our software is not running, or our software is running but isn't trying to control the relay, then the relay is in the same state. Only if the running program is actively trying to control it, then the relay should change state.

I have observed that when the power is off to the Pi, then the relay is in one state, and when power is applied the relay changes state, then when our program runs it change state again.

Is there a way to configure this relay so that the default state at power on and during boot and when no program is running is the same as when the power is off?

Thanks for any advice.

Hello matthewh,

have a look at the following link :

RevPi Connect Relai

Best regards
Giuseppe Pagano

Thanks Giuseppe.
For future readers, my interpretation of this is:
* The Connect SE follows the rules for the Connect (not the Connect 4)
* When power is off to the Pi, it is as if the relay is open
* As soon as power is applied, the relay becomes closed, and there is no way to change this
* The relay LED on the front of the device indicates closed -- LED off == relay open

I have found that I can use Pictory to set a default value for the RevPiLED variable. By setting this to 64, the default state is open. However, there is still a short period after power comes on that the relay is closed, before the default value is applied.

My use case is the same as the documented example: interrupt the power supply to a wireless router. I have had to go with: when the Pi is off, the router is off.