Wiring 2 x 12v heat beds in series

I have a couple of 12v heat beds laying around from tear downs/ spares and was thinking of combining a couple for a large dual bed. I have seen a number of similar questions answered previously but am still unclear the best way to do this.

Any thoughts on how I can safely wire them ?

I know I could just get a large silicon heater but I want to make use of some the spare parts I have.’

Jay

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Jaymcd0626
I have a couple of 12v heat beds laying around from tear downs/ spares and was thinking of combining a couple for a large dual bed. I have seen a number of similar questions answered previously but am still unclear the best way to do this.

Any thoughts on how I can safely wire them ?

I know I could just get a large silicon heater but I want to make use of some the spare parts I have.’

Jay

You can wire them in parallel to a 12 volt supply if the driver mosfet or relay can handle the current, or you can wire them in series to a 24 volt supply if the mosfet or relay can handle the voltage.

Problem is when they have totally different power ratings, temperatures could differ by a lot. i would rather have each one on its own control circuit, i.e. 2 MOSFETs and 2 thermistors.

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Hfleming
Problem is when they have totally different power ratings, temperatures could differ by a lot. i would rather have each one on its own control circuit, i.e. 2 MOSFETs and 2 thermistors.

Very true. I had made the stupid assumption that both heaters had the same resistance.

Oh OK, hmm. Have to see if my controller can support two separate heat EDS and thermistors. But I like the idea and agree it would probably work out better.