An example using a meanwell LDD-1000
a set of 2 wired in series - 24v
both sets of 2 wired in parallel - 24v
max current - 500ma
4x of those wired in series for all 4 is 48v fv. While an LDD can handle that you will need a power supply that can do at least 52v which can be expensive. Best bet is doing the above as you will only need 1a out of a 32v power supply. Then you could easily add up to 4 more with another LDD-1000 and still only need 2A.