Hej Mikkel!

You have to fix several things:

Get a decent powersupply, and separate micro and relay supply.

Get a propper supervisor ic, and use it for both micro and latches

Use a diode - 1N4148 - over each relay, to kill the noise at the source.

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Steve Taylor wrote:

0.1uF 100R across them works wonders for reducing ringing.

You answered:

I would like to avoid adding more parts than nescessary to save board space if possible. The circuit seems to work well without any extra parts.

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PCB real estate is expensive; we all know that. But it could easily becomme a lot more expensive to have a product fail due to lack of care.

BTW - is this a one of, or is it a thing to go in production? If so remember that the product must pass a EMC test!

Ha' en god søndag

Per Guldmann