Aros Flexus FM, User Manual

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E
XTERNAL PROTECTION DEVICES
MAGNETOTHERMAL SWITCH
As outlined above, the UPS has devices to protect against faults on the output and internal faults.
To set up the power line install a
magneto-thermal switch
upstream of the UPS with intervention curve C in
compliance with the EN 60947 specification, following the indications given in the following table:
Automatic external protections
Mains input
UPS Model
Single-phase input (P+N) Three-phase input (3P+N)
Separate bypass input (P+N)
Standard Ups
10 – 12 – 15 – 20 kVA
100A 100A N.D.
Ups with separate bypass
15 – 20 kVA
100A 63A 100A
Ups with separate bypass
10 – 12 kVA
63A 40A 100A
If the protection device upstream of the UPS interrupts the neutral conductor, at the same time it must also
interrupt all the phase conductors (quadri-polar switch).
Output protection (recommended selectivity values)
Normal fuses (GI) In (Nominal current)/7
Normal switches (C Curve) In (Nominal current)/7
Ultra rapid fuses (GF) In (Nominal current)/2
DIFFERENTIAL
In the standard version, the neutral from the mains power is connected to the UPS output neutral and the neutral settings
of the installation remain unchanged.
THE INPUT NEUTRAL IS CONNECTED TO THE OUTPUT NEUTRAL
THE DISTRIBUTION SYSTEM THAT POWERS THE UPS IS NOT CHANGED BY THE UPS
The neutral settings are changed only if an isolation transformer is installed or when the UPS operates with a
differential switch located upstream.
Make sure that the input neutral is connected correctly, because errors could damage the UPS
When operating from mains power, a differential switch located at the input intervenes so that the output circuit is not
isolated from the input circuit.
Extra differential switches can always be inserted at the output, and where possible, co-ordinated with the differential
switches at the input.
The differential switch upstream of the UPS must have the following features:
ƒ
Differential current adjusted to the UPS load value; an adequate margin should be kept to avoid delayed
interventions (recommended value: 100mA min. - 300mA)
ƒ type B or type A
ƒ delay greater than or equal to 0.1s