I would be interested to hear how members of this group are carrying out COC's for UPS feeds. I seem to be getting more of these all the time now. All of them are in industrial environments and sometimes involve the UPS feed to a DB or a feed from the UPS DB to 230V instruments in the filed.
My biggest concern is the PSCC and ELI.
There aren't any fault levels marked on the UPS. I presume that this would in any event change according to the amount of batteries installed.
I have heard people say that in the event of a fault the inverter will switch back to mains so therefore test the mains circuit to get the values however, this still presents problems in getting the readings.
Second question is testing of 525V feeds from MCC's to motors etc. I have one at the moment where I am to issue a COC for a 525V feed from MCC to 0.4KW motorised valve. My tester cannot test this voltage even though it will be 303V phase to earth. I am trying to get the engineers to give me the PSCC at the MCC but from previous experience they will give me the main switch kA rating and not the actual PSCC. Anyone else had these problems.
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