Specifications

MGE UPS SYSTEMS - Galaxy 3000 Specification 6 Effective: September, 2006
7. Temperature Compensated Charging: The battery charger shall be equipped with a temperature
probe to enable temperature compensated charging and adjust the battery float voltage to
compensate for the ambient temperature using a negative temperature coefficient of 3 mV per cell
per degree Celsius at a nominal temperature of 25°C.
8. Battery Capacity: The battery charger shall have sufficient capacity to support a fully loaded
inverter and fully recharge the battery to 95% of its full capacity within 6-8 hours.
B. Inverter
The UPS output shall be derived from a Variable Frequency Pulse Width Modulated (PWM) IGBT inverter
design. The inverter shall be capable of providing the specified precise output power characteristics
(specified in section 2.2.C) while operating over the battery voltage range. The inverter assembly shall be
constructed as a modular assembly to facilitate rapid maintenance.
C. Static Bypass – 100% Rated, Continuous Duty
The static bypass transfer switch shall be solid-state, rated for 100% continuous duty operation without
mechanical contactor device in parallel for higher reliability and consistent response time and shall
operate under the following conditions:
1. Uninterrupted Transfer: The static bypass transfer switch shall automatically cause the bypass
source to assume the critical load without interruption after the logic senses one of the following
conditions:
a) Inverter overload exceeds unit's rating
b) Battery protection period expired and bypass current is available
c) Inverter failure
2. Interrupted Transfer: If the bypass source is beyond the conditions stated below, the UPS will make
an interrupted transfer (not less than 100 msec. in duration).
a) Bypass voltage greater than + 10%, -10% from the UPS rated output voltage.
b) Bypass frequency greater than + 2 Hz from the UPS rated output frequency.
3. Automatic Uninterrupted Forward Transfer: The static bypass transfer switch shall automatically
forward transfer power, without interruption, after the UPS inverter is turned "ON" after an
instantaneous overload-induced reverse transfer has occurred and the load current returns the UPS’s
nominal rating or less.
4. Manual Transfer: A manual static transfer shall be initiated from the UPS Control Panel by turning
the UPS inverter off.
5. Overload Ratings: The static bypass transfer switch shall have the following overload characteristics:
a) 1000% of UPS output rating for 0.016 seconds (one cycle)
b) 150% for 1 second
c) 130% of UPS output rating for 1 minute
D. Output Static Switch – 100% Rated, Continuous Duty
UPS output shall be equipped with a 100% rated output static switch without mechanical contactor device
in parallel for higher reliability and consistent response time of 16.66 msec.
E. Microprocessor Controlled Logic
The full UPS operation shall be provided through the use of microprocessor controlled logic. All operation
and parameters are firmware controlled, thus eliminating the need for manual adjustments or
potentiometers. The logic shall include a self-test and diagnostic circuitry such that a fault can be isolated
down to the printed circuit assembly or plug-in power assembly level. Every printed circuit assembly or