68
UPS
INTERNAL PROTECTIONS
The table below shows the sizes of the UPS isolators and the battery fuses (SWBATT) which are all accessible from the front of
the UPS. Moreover, the table shows the maximum input and the nominal output currents.
Fuses must be replaced with ones of the same type and of the same rating, as shown in the table.
Isolators and currents
UPS
Mod.
Non-automatic switches
Battery isolator
Currents
[kVA]
UPS input / Separate bypass
UPS output / Maintenance
Battery fuse
Input
current
[A]
Output
current
[A]
SWIN / SWBYP (optional)
SWOUT / SWMB
SWBATT
Max
*
Nominal
30
63A(4P)
63A(4P)
80A gG 400V (22x58)
54A
46A
40
100A(4P)
100A(4P)
100A gG 400V (22x58)
70A
61A
*
The maximum input current refers to a nominal load (PF = 0,9), to a 346V+ input voltage, and battery charger under a 7A
charge.
SHORT CIRCUIT
If a fault occurs on the load, the UPS protects itself by limiting the value and the duration of the current supplied (short circuit
current). These values also depend on the UPS operating status at the time of the fault, which can be either:
UPS in NORMAL OPERATION: the load is instantly commutated to the bypass line (UPS 30kVA I
2
t=20000A
2
s; UPS
40kVA I
2
t=25000A
2
s): the input line is connected to the output with no internal protection (locked after t>0.5s)
UPS in BATTERY OPERATION: the UPS protects itself by supplying an output current which is about 1.5 the nominal
current for 0.5s, after which it shuts down.
BACKFEED
This UPS is also equipped with an internal protection against backfeed through metal separation devices.
An optional output on the relay board is available for activating a release device to be installed upstream from the UPS.
This UPS has an internal device (redundant bypass power supply) which, in case a fault occurs, activates the bypass
automatically, thus maintaining the load powered with no internal protection and with no limit on the power supplied
to the load.
Under such emergency conditions, any disturbance on the input line will affect the load.
Please see the paragraph “Redundant auxiliary power supply for automatic bypass”, in the “USE” section.
