46131-0598 <90-00018>
P
AGE
5
R
ESPONDER
P
ORTS
Responder ports send alarm information to alarm reporting
equipment.
All options
Ports 1 and 2 can be either an RS-422/485 or RS-232 interface.
The RS-422/485 receive input can be terminated with 182 ohms
(switch option).
If RS-232 is used on ports 1 or 2, RTS/CTS handshaking can be
used. RTS/CTS handshaking enables communication through an
external modem on ports 1 and 2.
Port 3 is not used.
Options -20 and -21
Port 4 communicates through a optional 202 Modem subassem-
bly that plugs into the main circuit board. The modem operates
as a Bell 202 full-duplex tone modem. It has a data rate of
1200 baud. The modem provides:
♦
Test points to measure the transmit and receive signal levels.
♦
A potentiometer to adjust the transmit level.
♦
An LED to indicate when the carrier signal is present.
The test points and potentiometer are accessible through a
window in the back panel of the APU.
All the responder ports communicate with either DCP, DCPF,
TBOS, or TABS protocol.
C
ONFIGURATION
P
ORT
To program the APU to operate, connect a programming paddle
or dumb terminal to the RS-232 configuration port. The paddle
plugs into the RJ-11 connector on the front panel. The dumb
terminal connects to C1 on the front panel or at P3 on the back
panel.
L
OCAL
A
LARM
AND
A
CKNOWLEDGEMENT
Wire external audible or visual devices, such as a bells or lights,
to the APU for local alarm monitoring. When there is an alarm,
a relay in the change-of-state (COS) circuit operates the device.
If the alarm device is operating and another alarm occurs, the
relay will pulse once.
Depending on how the APU has been programmed, the relay
returns to its non-alarm state either (1) when all the alarms
clear or (2) when a timer expires after 15 minues. Manually
reset the relay either by applying a ground at the ACK COS
input or by pushing the front panel acknowlege button.
CIRCUIT DESCRIPTION
UPDATED
