CMU-212 Cabinet Monitor Unit
Operations Manual
Eberle Design Inc.
Page 5
Section 2
MONITOR FUNCTIONS
2.1 CABINET POWER SUPPLY MONITOR
The CMU-212 will sense the C24VDC and +12VDC power supply sources. The
CMU-212 will also sense the C24VDC state in each Output Assembly as reported
by each AMU. Voltages equal to or greater than +22 Vdc and +11 Vdc respectively will not
cause a LFSA. Voltages at or less than +18 Vdc and +9 Vdc for 500ms or longer will cause
a LFSA. If the sensed voltage is less than +22 Vdc or +11 VDC for 200 ms or less, the
CMU-212 will not cause a LFSA. All other timing or voltage conditions may or may not
cause LFSA. A +24VDC failure or +12VDC failure during the programmed Minimum Flash
time or during a CMU-212 Power Failure will not cause a LFSA. The CMU-212 will report
the value of the +24 VDC and +12 VDC power supply sources in the Type 189 response
frame.
There is programming in the Datakey to d12 VDC power supply monitoring.
2.2 CONFLICTING CHANNELS MONITOR
For purpose of conflict determination, an active signal on either of the Green/Walk or
Yellow inputs associated with any of the 32 channels will be considered as that channel
being active. The Datakey will contain the permissive channel pair programming.
When any conflicting channels are detected as concurrently active for less than 200
milliseconds the CMU-212 will not cause a LFSA. When any conflicting channels are
detected as concurrently active for 500 milliseconds or more, the CMU-212 will cause a
LFSA. When any conflicting channels are detected as concurrently active for more than
200 milliseconds but less than 500 milliseconds, the CMU-212 may or may not cause a
LFSA.
2.3 SERIAL BUS MONITOR
The CMU-212 communicates with both Serial Bus (SB) #1 and #3. In SB #1 the CMU-212
is a Secondary device, polled by the ATC Primary device. On SB #1, the CMU-212 will
respond to the Serial Bus #1 Address defined by the ADDRESS 0 and ADDRESS 1 pins.
On SB #3 the CMU-212 is the Primary device, polling each AMU-214 Secondary device.
2.3.1 SERIAL BUS #1 ERROR
The CMU-212 will cause a FSA when a Type 61 or Type 67 Frame has not been received
from the ATC for greater than 1000 milliseconds. The first and second failures in a 24-hour
period will be a NFSA. The third failure in a 24-hour period will be a LFSA-R. If a CMU-212
Power Fail resets the LFSA-R, the SB #1 failure count will be reset to two, such that the
next SB #1 timeout results in a LFSA-R.
A SB #1 timeout failure during the programmed Minimum Flash time or during a CMU-212
Power Failure will not cause a FSA. The SB #1 Timeout function will be disabled if the SB
#1 DISABLE input is at a True (Low) state
2.3.2 SERIAL BUS #3 ERROR
The CMU-212 will cause a FSA when a Type 129 or Type 130 Frame has not been
received from each AMU for greater than 300 milliseconds. The first and second failures in
a 24-hour period will be a NFSA. The third failure in a 24-hour period will be a LFSA-R. If a
CMU-212 Power Fail resets the LFSA-R, the SB #3 timeout count will be reset to two, such
that the next SB #3 timeout results in a LFSA-R.
A SB #3 timeout failure during the programmed Minimum Flash time or during a CMU-212
Power Failure will not cause a FSA.
