PS_ON usage
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Hi!
I would like to use the PS_ON signal to be able to power on/off my 24V supply, which is not a PC supply. So, I will need to use a little relay.
How is PS_ON signal wired, on Duet side? How can I use it to drive my relay? Does it need some special protection?
Thanks,
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PS_ON is connected to an open-drain N-channel mosfet. You can use it to drive an SSR directly by connecting the negative control terminal to PS_ON and the positive control terminal to +3.3V or +5V. If you use to drive a mechanical relay, you must connect a flyback diode in parallel with the relay coil.
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Perfect!
Thanks.
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One of this can work? I use with raspberry pi for led lights
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Looks like there is an optocoupler? Do you have a link?
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Search some like arduino relay module.
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If you use the flyback diode, as its still a mechanical relay with a magnetic coil which can shunt a whack of voltage back when de-energised. Check the coil voltage you'll need to supply the positive side of the coil with the right voltage for the duet to switch the negative side of the coil. 5v or 3.3v coil probably makes sense in terms of being able to get the supply easily.
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The above boards seems to have an optocoupler, so no need to use a flyback diode on the Duet side. It is already included on the board, after the optocoupler, on the relay side (I think it is D2).
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Do you use the board finally?
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Non, I don't control my power supply yet…
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I will try to use the same for emule a button connected to one rpi gpio. Waiting the script now
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the whole fly back diode is confusing to me. I am using this relay http://modtronix.com/mod-rly2-5v.html and on that page it looks like the schematic has a diode. I have a 1N4001 diode on hand do i want to add it. If so where.
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That's a relay module, not just a relay, so you don't need to use a flyback diode with it.