MGE UPS Systems GALAXY PW 100, Installation And User Manual

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4.7.1 Steady State Voltage Regulation
For stable or slowly varying load conditions, the inverter output voltage is regulated to within ±0.5% in amplitude.
The frequency of the output voltage can theoretically be regulated to within 0.1% of the rated value, however the
output frequency range may be intentionally extended to a maximum of ±2 Hz so that the inverter can remain
synchronized with the bypass AC source and its inherent frequency fluctuations, thus enabling transfer of the load
to the bypass line at any time.
When the bypass AC source frequency returns to within the specified tolerances, the inverter is gradually re-
synchronized to the bypass line at a rate of 0.5 Hz to 2 Hz/s (as per the value personalized by the after-sales
support department), thus avoiding exposing the load to sudden frequency variations.
4.7.2 Transient Voltage Regulation
The inverter output voltage is not notably affected by instantaneous major variations in load characteristics.
This is made possible by the PWM (Pulse Width Modulation) chopping technique and the microprocessor-based
regulation system that instantly compensates for any variation. In particular, the inverter output voltage remains
/- 2% of the rated voltage for load step changes of 0 to 100% or of 100 to 0%.
The battery charge cycle takes place in two steps:
step 1: The battery is recharged at a constant current limited to 0.1C10 (i.e. 1/10th of the battery capacity specified
for a 10 hour discharge). The DC voltage increases with the battery charge until the charge level is reached.
step 2: The battery is recharged at constant voltage equal to the charge level. The charging current gradually
decreases until reaching a specified low value (floating current).
For vented lead-acid batteries, the rectifier/charger supplies the charging voltage for 0 to 255 hours (parameter
defined by the after-sales support department) and then the floating voltage. For sealed lead-acid batteries, the
charging and floating voltages are the same.
Galaxy PW ™ UPS 100 to 225kVA
Operation 4 — 10 86-133060-00 A00