P
AGE
4
46020-1297 <90-00038>
♦
RTS - Ready To Send
♦
CTS - Clear To Send
♦
DCD - Data Carrier Detect
♦
DSR - Data Set Ready
♦
DTR - Data Terminal Ready
Ports are programmed with switches or through the use of
downloaded databases, depending on the firmware being used
on the MAP.
Addressing the remote alarm and control devices is done using a
tri-state octal buffer and a tri-state octal D-type latch that forms
three parallel inputs/outpus. Redundant features of each buffer
and latch provide input/output interfaces for an optional 46019
Summary Alarm Module and a unassigned auxiliary input/
output.
The regulated power supply uses -21 to -56 VDC input power to
12 VDC and +5 VDC to the modules circuit board. The
+5 VDC output also is available at the edge connector for exter-
nal use. In addition, the power supply provides operating power
for an optional communications subassembly.
CIRCUIT DESCRIPTION
INSTALLATION
T
his sections consists of installing the communication subas-
sembly (if necessary), setting the MAP switches, and install-
ing the MAP in the shelf.
Subassembly
The 46020 MAP comes from the factory with a TTL bypass
subassembly installed. Refer to Fig. 2. If a different communica-
tions subassembly needs to be installed, follow these steps:
1.
Remove the hole plug from the front panel of the MAP.
2.
Remove the screws from the subassembly standoffs and remove the
existing subassembly by carefully pulling up on the subassembly.
3.
Install the new subassembly. Examine the connector pins to be
sure that each one goes straight into the socket. The subassembly
should sit down on the standoffs and the front panel should appear
straight in the MAPs front panel opening.
4.
Install the mounting screws.
5.
Set any straps and/or switches according to the subassemblys prac-
tice.