Signal definitions, Continued, 3 usm2 signal definition – Alpha Technologies USM2 User Manual
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©2000
™
704-587-B0-003 Rev.D
4. Signal Definitions
4.3 USM2 Signal Definition,
continued
Name:
Output Fail Alarm
Pin:
J3-10
Signal Type:
USM2 Discrete Output
Referenced to:
Common (J3-1, J3-12)
Description:
This USM2 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.
Active State:
HIGH
How to Test:
Remove the XM2’s AC output fuse; verify J3-10 is LOW. Return the XM2’s fuse;
verify J3-10 is HIGH.
Name:
Test/Reset
Pin:
J3-11
Signal Type:
USM2 Discrete Input
Referenced to:
Common (J3-1, J3-12)
Description:
This USM2 input controls remote test of the XM2’s inverter and allows reset of
a latched USM2 Equipment Fail Alarm. This control signal originates from
the transponder.
Active Means:
An active Test / Rest 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 that the Test/
Reset pin has been activated. The pin will be considered active by the USM2
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. Disconnected from a transponder the USM2-SEG input defaults
to the inactive state.
Inactive State:
HIGH
How to test:
To perform a test at the XM2, disconnect the transponder from the USM2.
With line and battery applied to the XM2, carefully short and hold the Test/
Reset J3-11 to ground (J3-1), the XM2 will immediately start inverter test
mode. Release J3-11 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 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., J3-6 change to inactive).