Models 947, 948 and 960 Leak Detectors Operations and Service Manual
2-11
2.3.3 Host Serial Port J123 Pinouts
The Host Serial Port is used to interface the 947/948/960 to a PLC or host computer via an
RS-232 connection. Table 2-4 provides details about the connection.
J123 connections are referenced to the chassis ground and are not isolated. Electrical
characteristics comply with EIA/TIA Standard EIA/TIA-232-E.
18
MSD D
Active High
BCD Leak Rate
20, 21
+24 VDC for Output Sourcing
24, 25
Ground for J121
Table 2-4
J123 Pinout Summary
Pin on
J123
Signal Name
Description
1
Shield
Shield for J123, System Ground
2
RXD
RS-232 Data
3
TXD
RS-232 Data
4
CTS
RS-232 Flow Control
5
RTS
RS-232 Flow Control
6
DTR
RS-232 Flow Control
7
Data Ground
Signal Return for J123
20
DSR
RS-232 Flow Control
Table 2-3
J121 Output Summary