Approximate Guide to Socomec UPS Sizing:
Determine Wattage for each device then calculate the total. Wattage can be found on the product specifications sheet for the device.
Example 55w, rounded up to 60w | for 1 NVR4PRO3 + 3 VSIPC-4BIRMG + 2TBHDD
Check load column W. This shows the load for certain UPS and how long you can expect.
If we use the UPS1000VA, NETYS-PE 1000, at 20% load it would get over the 45 minute at 120w as we are using half of that. It is not directly linear but you can expect it last longer.