Electronic Compartment Component Descriptions and
Maintenance Procedures
2
2.1
Power Supplies
2.1.1
Power System Module
Overview
The Power System Module (PSM) is a 110/230 VAC switching power supply that provides 24
VDC operating system voltages. It also provides 110/220 VAC conditioning. The 24 VDC power
supply provides high speed switching with power factor correction and universal input. The
PSM is a stand-alone system consisting of a power supply, filtering, circuit fuse protection and
a power monitor board.
Power
System
Module
Line Voltage Selector Switch
Fuse Holder
Figure 2-1
Power System Module Location in EC
AC Line Input
AC power input to the power supply is from the Power Entry Control Module. A line cord from
the PECM plugs into the front AC receptacle of the power supply. A primary Line Voltage
Selector selector switch (located above the AC receptacle) must be set to match the primary
AC voltage input from the Power Entry Control Module.
Maxum II Reference Manual
Manual, 7/2017, 2000596-001
13
