Xtreme Power Conversion Corporation
P91, TX91, TX91L, TXVR Service Manual
Page 12
Uninterruptible Power Supply
5.2 CNTL board (Control Board)
The CNTL board is the core of the UPS system. It controls the actions of the semiconductors and other mechani-
cal switches, the display of the LED/LCD, the sound of the buzzer, the communication with the computer, and
other important tasks.
5.3 Communication board
The Communication board provides RS232/USB interface to the users, and it also provide one EPO port
to cut off the output immediately.
5.4 EMI board
The EMI board can prevent the UPS from external electronic/magnetic noise generated by other electronic
systems, and also prevent other systems from the noise generated inside of the UPS system. And the MOV is also
on the EMI board which can absorb the surge to protect the UPS system.