Delta MCS-1800 - Manual (Page 11)

DELTA MCS-1800 3U Power Sh elf
Installation, Operations and
Maintenance Manual
3-1
3 Power Supply Unit (PSU)
3.1 Description
This rectifier units are rated at full load when operated from high line. For Low operation, the output is
derated to half load. This derating is automatically activated from the Alarm Control Unit (ALU). However,
the rectifier can operate on a stand-alone basis, if this ALU is removed or nonfunctional.
Warning: In the absence of the ALU, the automatic derating of the rectifiers at Low Line is not effective.
Exceeding the 50% load limit at Low Line may damage the rectifiers.
The modular design provides the flexibility to configure and expand the system as the load demand
increases. Each rectifier unit is swappable with front access for ease of maintenance without system shutdown,
providing uninterrupted service.
The rectifier unit has an active power factor correction of greater than 0.99 for maximum AC utilization.
Each module is equipped with an AC switch located at the front of the module. Figure 3 shows a front view of
PSU.
Note: The equipment is only for installation in a Restricted Access Location.
The equipment is used on a stationary equipment/unit only.
3.2 Specifications
Detailed rectifier specifications are provided in the following sections.
3.2.1 Electrical
Detailed electrical specifications for the rectifier are provided in this section.
3.2.1.1 Input
Table 6 displays the rectifier input specifications.
Table 6 Rectifier Input Specifications
Specification Value
Input Voltage
90VAC to 275VAC, Single Phase, (during 176 to 150VAC
derated to 80% Load, during 150 to 90VAC derated to 50% Load)
Input Current 12 Amps at 176 VAC, Full Load
Line Frequency 45 to 65 Hz
Power Factor >0.99, at 220 VAC Input, Full Load
THD <5%, at 220 VAC Input, Full Load
Efficiency
>90%, Full Load (-48V Version)
>88%, Full Load (+24V Version)
Inrush Current <12 Amps (peak), 220 VAC, Full Load, Cold Start
Start Time Delay
(Walk-In)
3 to 10 seconds
Protection Fuse