Comtech EF Data SDM-300L - Manual (Page 34)

SDM-300L Satellite Modem Installation
Rev. 2 2–13
Notes:
1. IDR configuration connector pinouts:
a. Backward alarm relay contacts are named for normal no fault
conditions (BWOx-C connected to BWOx-NC if no fault).
b. Backward alarm inputs should be grounded or pulled logic low to clear
the alarm.
c. Signals MF, DF, and DMA are open-collector, high-impedance (if
faulted). MF and DF are used by a backup protection switch if the
modem is used in a redundant system.
d. Relay contacts DF-C and DF-NO are named for faulted condition (DF-
C connected to DF-NO, unless demodulator [Demod] fault).
2. D&I/ASYNC interface connector pinouts:
a. With regard to alarm relay contacts, COMM is connected to NO when
there is no fault. COMM is connected to NC in a faulted condition.
b. Signals MF, DF, and DMA are open-collector, high-impedance (if
faulted). MF and DF are used by a backup protection switch if the
modem is used in a redundant system.
3. The breakout panel provides the external connections between the modem
and the terrestrial equipment when the modem has a 50-pin connection.