UPS and Surge Protection for the UK market

[Anonymous user]

Hi guys,

I'm in the process of researching for purchasing a UPS unit and two Power Distribution Units (PDU) to be installed in a new office in London. I called the APC sales department and talked to an APC sales rep that recommended SMX3000HVNC based on the load I provided, but it only has 2 IEC320 C19 output outlets and I would like to power 4 PDUs.

We have two 16A wall outlets of type IEC 309 2P+E of which I will use one wall outlet to power the SMX3000HVNC using an IEC 309 2P+E to IEC 320 C19 for the input connection, and then I would like to use the other wall outlet to connect other PDUs that have surge protection, which APC does not provide on most of their PDUs. 

My dilemma is that I seem to have forgotten my electrical foundations and how to know how much current my equipment needs if only power in Watts and voltage operating ranges are provided. I'm not so sure that the second 16A outlet would support connecting a PDU that has multiple C19 output outlets and then daisy-chain/in sequence and still be able to support 16A for the PDU at the end of the daisy-chain without worrying about the first PDU in the chain. If I know that the nominal operating voltage a device needs and its maximum power draw in Watts, is it as easy as I = W/V and then I just add all calculated max currents to know if a cable or PDU will be able to support the current draw and not trip or overheat?