CDX800 DESCRIPTION
2.6.4.
Connection of PORT2 connectors (M-BUS)
Panel socket RJ45.
Pin
No.
Signal
mark
Description
Data flow
direction
1
SGND
Signal and supply ground
2
SGND
Signal and supply ground
3
TxRx-
M-BUS B (-)
Input/Output
4
TxRx+
M-BUS A (+)
Input/Output
5
TxRx-
M-BUS B (-)
Input/Output
6
TxRx+
M-BUS A (+)
Input/Output
7
+12V EXT External power 10,8 ÷ +15,6V
8
+12V EXT External power 10,8 ÷ +15,6V
ATTENTION! External supply is for converter M-BUS!
The converter must have external power supply because of galvanic separated.
Circuit example of the meter with modem CDX 800 with data length less then 10 m:
17
Pin 1 – SGDN
Pin 2 – SGND
Pin 3 –
M-BUS
(-)
Pin 4 –
M-BUS
(+)
Pin 5 –
M-BUS
(-)
Pin 6 –
M-BUS
(+)
Pin 7 – +12V EXT
Pin 8 – +12V EXT
Modem CDX 800
SGND
M-BUS (-)
M-BUS (+)
Meter
SGND
M-BUS (-)
M-BUS (+)
Meter
DC
+
