PowerWalker VFI 30000TP 3_3 BE - Manual (Page 53)

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EN
9. Procedures of DC switch-on:
Activate DC switch-on function set under UPS bypass mode
Make sure that “+”, “-” and “N” wires of batteries are properly connected to UPS
Switch on batteries
Lightly touch ENTER
Manually conduct switch-on order within about 1min after LCD self-inspection
7.2 Parallel machine operation
Redundancy introduction
N+X is currently the most reliable power supply structure, in which N indicates the minimum
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 registers
55kVA, we can use 20KVA for N+X design. With N taking up 3, X can be selected in ac-
cordance 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 almost 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 sys-
tem 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 reli-
ability is always a focus.
PowerWalker VFI 30000TP, 40000TP 3/3 BE/BI 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).
Note!
UPS will be switched off automatically if there is no operation within 1min after LCD
self -inspection is completed!