How do I Connect Loads to My UPS Power Supply?

UPS mains power and load connections is reasonably straight forward. In the UK, UPS power supplies up to 3kVA are supplied as standard with power cords to plug into a BS 1363 wall sockets. Hardwired versions are available for some models as a special order and are connected to a fused spur. Above 3kVA, UPS systems are hardwired with some UPS models up to 10kVA offering a mixture of hardwired and local output socket connections.

UPS power supplies under 10kVA will offer either C13 or C19 outlets or a mixture of the two. These are the IEC sockets, which in the UK we sometimes refer to as kettle-lead types. C13 outlets are rated at 10A, 250Vac and C19 at 16A 250Vac. Some small UPS below 1kVA may also offer BS1363 UK or Schuko outlets, making it easier to connect plug-in loads.

A UPS system may be installed with a power distribution unit (PDU) which provides additional outlets. The PDU will have a C13 or C20 plug or be hardwired for connection to the UPS. It is important to ensure that the total load on the PDU does not exceed the total capacity of the UPS outlet it is connected to or the UPS itself.

So, to connect the loads to be protected to a UPS system, you ned to list the number of loads and their plug requirements and select a suitable UPS power supply (and potentially PDU) arrangement.

Note, it can be useful to label each load connection, whether direct to the UPS or PDU for later reference, especially in server racks. This can help with load planning and also business continuity testing to ensure every critical IT load is UPS supported.