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User's Guide ______________________________________________________________________
120 _________________________________________________________________ M210482EN-B
External Connector J4 - Maintenance Line
Maintenance line is intended for on-site maintenance and can be used
with a Ceilometer Maintenance Terminal, PC, or other terminal.
Table 25
Maintenance Line
Property
Description / Value
Connector (J4)
Female five (5) pin M12 connector
(e.g.
Lumberg RKF 5 / 0,5 M)
Mating connector type
Male five (5) pin M12 connector (e.g.
Lumberg RST 5-644)
Baud rate
9600 default and standard
300, 2400, 4800, 9600, 19200, 38400,
57600 bps available
Distance to operate
300 m (1000 ft) at 2400 baud with typical
communication cables
Standard character frame
1 Start Bit
8 Data Bits
No Parity
1 Stop Bit
Standard character code
USASCII
Pin connections
See Figure 25 below (RTS/CTS not used).
Figure 25
Pin Connections of Connector J4
Overvoltage protection in
each circuit
Primary Noble Gas Surge Arrester
Secondary VDRs, Transient Zener Diodes
or normal Diodes