OMNIGRID Connect
Kamstrup A/S · 5512-2065_A1_GB_BSI
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8.
Extension modules
8.1
RS-485 multi-drop bus
Extension modules are interconnected using the RS-485 duplex multi-drop bus with following static
configuration:
•
Baud rate:
19200 bps
•
Data bits:
8
•
Parity:
Even
•
Stop bits:
1
Communication is based on MODBUS RTU.
Key parameters:
•
Network topology:
Star or daisy-chain
•
Termination resistors:
No (not required)
•
Cable length of RS-485 network:
< 5 m
•
Galvanic isolation:
Yes
•
Terminal block:
137 A/- and 138 B/+
Every connected extension module (i.e. MODBUS device) uses static address. Only Kamstrup ap-
proved extension modules are allowed.
Static MODBUS address map must be programmed into the extension module before/during instal-
lation.
MODBUS address
Type
Manufacture/product
Reference
1
Power Analyzer (PA)
IME / Nemo D4-Le
Section 0
2
PLC
Allen-Bradley / Micro820
Section 8.3
3
Power Analyzer (PA)
Circutor / CVM-MINI
Section 8.4
4
Reserved
-
-
