MGE UPS Systems GALAXY PW 100, Installation And User Manual

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4.6.1 Single UPS Unit (On-line mode)
In the event of a UPS shutdown (initiated by the user or by an internal protective device), the load is automatically
transferred to the bypass AC source. If transfer conditions are satisfied, transfer takes place instantly, without inter-
ruption to the load.
NOTE Transfer conditions are not satisfied when bypass AC source characteristics are
outside tolerances (voltage: ±10%. frequency as per personalization. phase sync
with inverter ±3°).
In the event of a major transient overload (greater than 1.65 In), immediate transfer takes place as above, without
interruption to the load.
The return to the inverter is automatic when the overload disappears if the number of possible returns has not been
reached (0 to 255, programmable by personalization). If this number has been reached, the load continues to be
supplied by the bypass AC source. This operating mode allows start-up of load devices causing high inrush currents.
This system requires satisfied transfer conditions. If the conditions are not satisfied, the inverter will current limit to
165% of its rated current for 1 second before stopping.
In the event of a small but extended overload (i.e. a continuous level of power exceeding the full rated load), the
inverter will continue to supply power for a period depending on the magnitude of the overload (10 minutes for a
125% overload, 1 minute for a 150% overload). See the overload curve in Figure 4-11.
◗
In all the above cases, inverter shutdown and supply of the load via the bypass AC source results in the
following on the control panel:
- light 4 goes off,
- activation of the buzzer (continuous beep),
- light 3 shines green,
- the message "LOAD NOT PROTECTED, ON-LINE MODE" is displayed.
4.6.2 Parallel UPS Without Redundancy
WARNING During maintenance operation, when CB1 (MBP) is closed and CB2 (UPS
ISOLATION) is open, each UPS control panel display will show a message
“LOAD PROTECTED” when the UPS is placed in ON-LINE MODE. In this
mode the critical load is not protected because it is supplied by the mainte-
nance bypass power.
Galaxy PW ™ UPS 100 to 225kVA
Operation 4 — 8 86-133060-00 A00