Specifications

Galaxy 5000 technical specifications
MGE UPS SYSTEMS SPTC5 500 UK – 09/2005 page
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2. Technical specifications
2.1 Operating principle
Purpose
These technical specifications present the Galaxy 5000 three-phase uninterruptible power system (UPS),
implementing sixpack IGBT modules and installed in series between the distribution system and a set of
critical loads. This type of system is designed to supply the application with high-quality energy (precise
tolerances) that is available without interruption (no outages or micro-outages) whatever the conditions on the
distribution system.
The Galaxy 5000 UPS configuration may comprise a single or parallel UPS units, with or without redundancy.
Operating modes
Galaxy 5000 UPSs are the double-conversion type (VFI as per IEC 62040-3/EN 62040-3), that regenerate the
output voltage and frequency. This ensures consistently high-quality voltage to the critical loads and an
isolation from the distribution system disturbances.
UPS operating modes are presented below (fig. 2).
Normal
(AC power present and within tolerances)
The load is supplied via the double-conversion line (rectifier/charger and inverter).
The rectifier is supplied by the normal AC input. It in turn supplies the inverter with the necessary DC current
and the charger with the DC current required to maintain the battery-charge level. The inverter supplies the
critical loads with a precisely defined, high-quality voltage that is free of outages.
Operation on battery power
(AC power has failed or is outside tolerances)
When AC power fails or its characteristics are no longer within set tolerances, the inverter automatically
disconnects from the rectifier and operates independently on power supplied by the parallel-connected
battery. The battery is also disconnected from the charger.
Recharging
(AC power present and within tolerances, following operation on battery power)
When AC power returns to within tolerances, the rectifier supplies the inverter and the charger recharges the
battery. The inverter supplies a voltage identical to that under normal operating conditions.
Automatic bypass
(Automatic transfer to the bypass AC input)
In the event of overloads exceeding UPS capacities or shutdown (voluntary or not), the static switch makes
possible no-break transfer of the critical loads to the bypass AC input. Load transfer back to the inverter takes
place automatically when the UPS is turned back on. Load transfer can also be forced by the user via the
user-machine interface (UMI), following confirmation of the order.
Manual bypass (maintenance and tests)
(Voluntary transfer to the bypass AC input)
The manual bypass switch isolates the inverter output and the static switch for maintenance operations. It is
then possible to test or repair the UPS without interrupting the loads, which remain supplied directly with AC
power.
ECO mode (single-UPS configurations)
(Optimum efficiency when bypass AC power is within tolerances)
ECO mode, configured by the user, is a means to increase UPS efficiency when bypass AC power is within
tolerances. The load is supplied with bypass AC power via the static switch. If bypass AC power fails or goes
outside tolerances, the load is transferred (no break) to the inverter. When normal conditions are restored, the
load is again transferred without a break to the bypass AC input. The user can, at all times, force transfer from
ECO mode to normal mode.