Don’t know if it is reccomended Dave, but to be honest I use one for the surface and another for the mix rack. I just got two cheap stand alone units cost me about £35 each, just in case some fool kicks a plug out somewhere. saves waiting for a re-boot. I know another owner has 2 fancy rack-mount UPS units one installed in the rack with the iDR10 (non standard rack) the other in a rack at FOH with the fibre switch he uses for comms between the rack and the surface.
Can’t do any harm now can it.

HI Wolfgan I believe it only makes sense if the units are “On Line” as you need seamless changeover to back-up.
The cheap units I use are by a company called Trust, these units I believe are made in Holland.(www.trust.com/14938) The model number is PW-4095T 950VA UPS. I believe this unit has sufficient capacity to run a rack with two supplies or a surface + back up PSU
I know other guys use APC and they all work fine I am sure.
I purchased my units (I have them on the office PC’s as well)through CPC/Farnell but again I am sure the same or simmilar units are available through local suppliers. The down side of these particular units is they are NOT rack mount but I live with that.
Mr. B