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Models 375-31H Area Monitor with Neutron Detector
Section 4
Ludlum Measurements, Inc.
Page 4-3
January 2021
BYTE1
0
x
BYTE2
x
x
BYTE3
x OR
x
BYTE4
x
x
BYTE5
.
.
BYTE6
x
0
BYTE7
Audio Status
=1=on
BYTE8
High Alarm Status =1=on
BYTE9
Low Alarm Status =1=on
BYTE10
Over Range Status=1=on
BYTE11
Monitor Status
=1=on
BYTE12
Error Code
BYTE13
Carriage Return (ODH)
BYTE14
Line Feed (0AH)
The RS-232 data includes the
current radiation readings and the
current condition of the status
lights. The data is presented in the
following format:
RS-232 Output
With the
CAL MODE
dipswitch in the left position, the Model 375-31H
dumps RS-232 data onto pin 4 of the 9-pin connector every two seconds.
9-Pin Remote Data Connector
(female sockets)
The 9-pin connector provides output signals from the instrument and
input voltage to the instrument. The pin assignments are:
pin1-
+BATTERY
pin2-
GND IN
pin3-
FAIL_L
pin4-
RS232 DUMP
pin5-
ANALOG OUT
pin6-
CHASSIS GND
pin7-
HIGH ALARM_L
pin8-
EXT RESET_L
pin9-
+5VDC OUT
The
FAIL
and
HIGH
ALARM
digital signal outputs are open drain 2N7002
outputs, able to sink about 50 mA each.