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Low trigger relay issues

1 Views - Created 15 days ago

15 days ago

Posted by:
nicusor.stoica

nicusor.stoica Avatar

I am using a low level trigger relay board and when the power is lost the pins go low for a small period of time then everything goes back to normal, why is that happening? Or should I switch to a high level trigger relay board?

15 days ago

Posted by:
nicusor.stoica

nicusor.stoica Avatar

I meant to say when the power is lost and the system boots back up. I could post the code if necessary.

15 days ago

Posted by:
andrew

andrew Avatar

Location:
United Kingdom

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Hello

If the power is lost the MCP23017 IO chip will reset to its default state with the pins set to inputs, so any pin that was outputing a high level voltage will go to 0V.

Using a relay board with high level triggering or putting an inverter between the outputs on the IO Pi Plus and your relay board should fix the problem.

15 days ago

Posted by:
nicusor.stoica

nicusor.stoica Avatar

Quote from andrew
Hello

If the power is lost the MCP23017 IO chip will reset to its default state with the pins set to inputs, so any pin that was outputing a high level voltage will go to 0V.

Using a relay board with high level triggering or putting an inverter between the outputs on the IO Pi Plus and your relay board should fix the problem.


Thank you so much !

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