
Installation Instructions
OS-1933-E3-003
044-05243 Rev A
2-7
External Alarms (EA)
The External Alarm input connections are made at the terminal block located at the rear of the Control Module.
The contacts accept a 28 – 16 AWG wire. The alarm cable connector is shown in Figure 2-4 and the wiring
procedure is detailed in Table 2-9. The external alarm inputs require activation and configuration via the
System/configuration page. The External Alarm channels are default disabled.
Connect the external alarms as instructed in Table 2-9.
MCPA
Install the MCPA as instructed in Table 2-10. The MCPA RF switch, indicator and quarter-turn fasteners are
shown in Figure 2-7 and the 21-pin D-Sub connector is shown in Figure 2-8.
CAUTION:
Do not slam the MCPA into the subrack. Forcing the MCPA into the subrack may cause the
pins on the 21-pin D-Sub connector to become recessed or broken.
A blank panel must be installed in any empty MCPA or RFCU slots before operation of the OS to prevent
overheating and ensure proper system airflow.
Table 2-8 Form-C Alarm Terminal Block Relay Connections and Conditions
Relay Continuity Measurement - No AC Applied or All Rectifiers Faulted
Minor
Major
Critical (All)
NO - C
Closed
NO - C
Closed
NO - C
Closed
NC - C
Open
NC - C
Open
NC - C
Open
Relay Continuity Measurement - System On, No Alarms
Minor
Major
Critical (All)
NO - C
Open
NO - C
Open
NO - C
Open
NC - C
Closed
NC - C
Closed
NC - C
Closed
Relay Continuity Measurement - System On, All Alarms On
Minor
Major
Critical (All)
NO - C
Closed
NO - C
Closed
NO - C
Closed
NC - C
Open
NC - C
Open
NC - C
Open
Table 2-9 External Alarms Connection Procedure
Step
Action
1
To install appropriate wiring, disconnect terminal block from booster.
2
Strip wiring insulation approximately 7 mm (0.3 in).
3
Use slotted screwdriver with maximum width of 2.5 mm (0.1 in) to back out terminal screws enough to
allow wire insertion.
4
Insert stripped wire into terminal and tighten set screw 2 inch pounds maximum.
5
Via the System/Configuration page (see Chapter 3) enable the appropriate external alarm channels.