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Unfortunately, it is not possible to keep the relay contact open when the Power is off: the RevPi connect is equipped with a relay that is normally closed by default. See here: (8) Relay contact is closed when a device power is off - Revolution Pi Forum
How to configure output relay behaviour on Connect SE
Have a look at the following link: https://revolutionpi.com/forum/viewtopic.php?t=4111
How can I check whether a digital output has taken over the written value?
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