PowerWalker VFI 20000TP 3/3 BX, User Manual

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EN
4.2 Parallel machine operation
1. Redundancy introduction
N+X is currently the most reliable power supply structure, in which N indicates the mini-
mum UPS number required for the total load and X is the redundant UPS number, namely,
the malfunctioning UPS number that the system can simultaneously bear. The larger X is,
the higher reliability of system will be. For instance, if the total load of a customer regis-
ters 55kVA, we can use VFI 20000TP 3/3 BX for N+X design. With N taking up 3, X can
be selected in accordance with reliability degree or cost requirement. Supposing customer
selects X=2 and equalized UPS power supply is 11kVA for each unit, when one set of
UPS breaks down with malfunction, the remaining four sets will provide power with al-
most 14kVA equalized current; if two sets of UPS fail, the remaining three sets of UPS are
supposed to provide power supply with almost 18kVA equalized current. The maximum
allowance of this system is for two sets of UPS going down at the same time, the chances
of which are much smaller than those of one UPS malfunction. Therefore, the reliability
degree can be largely enhanced, making it an optimal mode for application in locations
where high degree of reliability is always a focus.
The Series UPS is capable of direct parallel connection, which only requires the parallel
connection wires (optional) for 2 to 8 sets of UPS in parallel connection in order to realize
power redundancy (N+X).
2. Parallel machine wire connection drawing
Optional kit