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Information on Online and On Battery operation of 3:1 Symmetra UPS systems


Where can I find information on the Online and On Battery operation of 3:1 Symmetra UPS systems?

Product Line

Symmetra Power Array
Symmetra LX


3:1 (International) UPS systems only


This document is designed to provide Information on Online and On Battery operation of 3:1 Symmetra UPS systems


When a Symmetra 3:1 is operating On-Line it is drawing balanced power from all 3 phases, i.e., it is drawing the same current from each of the 3 phases. This is typically 25 amps per phase with a maximum 16KVA load. The 3 phase power is fed to all the Power Modules where it is filtered and converted to single phase and sent to the output. The nominal input voltage range is 380 or 400 or 415.

(220 x 1.7 = 380; 230 x 1.7 = 400; 240 x 1.7 = 415. Where 1.7 = square root of 3)

The Symmetra 3:1 will run On-Line for inputs between 290 VAC and 480VAC. The output voltage can be set to either 220 / 230 / 240 VAC at 50 or 60 Hertz.

If any one of the phases fails, the Symmetra will still operate On-Line but will pull more current from the other 2 phases. In this case it will draw no more than 60 amps per phase . If phase A or B fails, then the PowerView will report "Bypass Out of Range". If phase C fails, there is no notification message on PowerView. You will manually have to check the PowerView and read the input voltages.

If a second phase fails, then the Symmetra will go to On Battery operation and report "Bypass Out of Range" on the PowerView. Likewise, if all 3 phases fail it will go to On Battery operation.

When Symmetra 3:1 is On Battery it will provide single phase output power. The output voltage can be set 220 / 230 / 240 VAC. The output frequency can also be set to either 50Hz or 60Hz.

Please Note: While current is evenly distributed across all three phases while Symmetra 3:1 is on-line, all current will draw from phase 1 if the UPS is in bypass unless the optional Symmetra Bypass Transformer is in use.

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