Signal definitions, Continued – Alpha Technologies USM2.5 Status Monitor User Manual
Page 19
4. Signal Definitions
19
704-683-B0-004, Rev. D
4.1 USM2.5 Signal Definition,
continued
Name:
Output Fail Alarm
Pin:
J4-10
Signal Type:
USM2.5 Discrete Output
Referenced to:
Common (J4-1, J4-12)
Description:
This USM2.5 signal indicates the state of the AC output. A non-
latching signal, the Output Alarm will match the state of the
power supply output in real-time.
Active Means:
The XM2’s AC output has failed.
Active State:
LOW
Inactive Means:
The XM2’s AC output is OK.
Inactive State:
HIGH
NOTE:
Removing the output fuse will result in a loss of power to the cable system (load).
Do not attempt this test without first transferring the load to a Service Power Supply
How to Test:
Remove the XM2’s AC output fuse; verify J4-10 is LOW. Return
the XM2’s fuse; verify J4-10 is HIGH.
Name:
Test/Reset
Pin:
J4-11
Signal Type:
USM2.5 Discrete Input
Referenced to:
Common (J4-1, J4-12)
Description:
This USM2.5 input controls remote test of the XM2’s inverter and
allows reset of a latched USM2.5 Equipment Fail Alarm. This
control signal originates from the transponder.
Active Means:
An active Test / Reset pin indicates that the XM2 has been
commanded to initiate and hold a remote inverter test.
Active State:
LOW, a transition from HIGH to LOW will indicate to the USM2.5
that the Test/Reset pin has been activated. The pin will be
considered active by the USM2.5 for the duration that the pin is
held LOW.
Inactive Means:
The XM2 is not commanded to perform or hold a remote inverter
test. Any previously held test will be ended when the input is
transitioned from active to inactive.
Inactive State:
HIGH
How to test:
To perform a test at the XM2, disconnect the transponder from
the USM2.5. With line and battery applied to the XM2, carefully
short and hold the Test/Reset J4-11 to ground (J4-1), the XM2 will
immediately start inverter test mode. Wait at least 1 minute then
release J4-11 from ground and the inverter test mode will end,
and any latched Equipment Fail Alarm should clear.
Resetting a latched Equipment Fail Alarm:
If a USM2.5 Equipment Fail Alarm is latched when the Test/
Reset pin is made active and a successful inverter test is
completed, the Equipment Fail Alarm will be cleared (i.e. J4-6
change to inactive).