12v into a 24v bed will take for ever to heat up (and probably never get over 60c)
You can't convert a 24v heated bed to 12v unless it was deigned to do so.
You can still use it, if you buy a 24v power supply and a external mosfet.
It might be worth looking at upgrading your entire system to 24v. Depends what it is and how much work is involved....
Edited 4 time(s). Last edit at 02/19/2021 03:50AM by Dust.