MGE UPS Systems GALAXY PW 225KVA - Manual (Page 18)

1.6 Electrical Parameters for Selecting Protective Devices
1.6.1 Normal AC Source
The parameters given in Table 1-1 can be used to determine the required rating of the upstream protective circuit
breaker on the normal AC input for one single-UPS or parallel-UPS unit.
Normal and Bypass AC Input:
number of conductors 3 phases
rated voltage and tolerances 480 V ± 10% (adjustable to ± 15%)
rated frequency and tolerances 60 Hz / ± 10%
IMPORTANT It is essential to choose the type of circuit breaker according to its breaking
capacity and the prospective short-circuit current at its place of installation.
This choice must also be made so as to protect the static-switch semicon-
ductors with respect to the maximum permissible currents and ensure
discrimination between the UPS output fuses and the downstream
protection devices.
Table 1-1: Electrical Parameters for Normal AC Source.
Electrical parameters for the normal AC source
rated current normal AC source
UPS rated current In for unit: for 25% for 50%
output with battery at start without battery (2) overload (3) overload (3)
in kVA of charge cycle (1)
100 166 159 199 239
130 214 205 256 308
150 245 236 295 354
180 295 283 354 425
200 328 316 395 474
225 332 320 400 480
(1) The rated normal AC source currents (In) have been determined for a rated phase-to-phase voltage of 480 V,
a battery with a 10 minute backup time at the beginning of its charge (412 x 1, 2 = 494 Volts) and full rated load
with a power factor of 0.9.
(2) The rated normal AC source currents (In) have been determined for float charging voltage and full rated load
with a power factor of 0.9
(3) The normal AC source currents given for an overload of 25% or 50% are maximum values. They have been
determined for a battery with float charging voltage and a load power factor of 0.9. When choosing the circuit
breaker rating, use the "rated current" column and check that the circuit breaker tripping curves are compatible
with the values in the overload columns.
Galaxy PW™ UPS 100 to 225kVA
Introduction 1 — 6 86-133060-00 A00