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SITRANS RD300
A5E31917845
SITRANS RD300 – OPERATING INSTRUCTIONS
Page 9
Voltage Input Connections
The meter is capable of accepting any voltage from -10 VDC to +10 VDC.
Modbus RTU Serial Communications
Serial communications connection is made to an RJ45 connector
labeled M-LINK. For interfacing to the RD300, use the 7ML19306AF for
RS-232 or the 7ML19306AG for RS-485. The same port is used for
interfacing with all expansion modules (
e.g.
external relays, digital I/O).
Relay Connections
Relay connections are made to two six-terminal connectors labeled
RELAY1 – RELAY4. Each relay’s C terminal is common only to the
normally open (NO) and normally closed (NC) contacts of the
corresponding relay. The relays’ C terminals should not be confused
with the COM (common) terminal of the INPUT SIGNAL connector.
Relay Connections
C
NO
NO
NC
NC
C
RELAY4
RELAY3
4
3
6
5
2
1
C
NO
NO
NC
NC
C
RELAY2
RELAY1
4
3
6
5
2
1