Specifications

CDA70 MODEM DESCRIPTION
13
Circuit example of the meter with modem CDA70 with data length less than 10 m:
Circuit example of the meter with modem CDA70 with data length more than 10 m:
At RS485 data cable more than 10 m it is need to use over-voltage protection on
CDA 70 modem side!
External or internal power supply of expansion port RS485 it is can evoke by wiring
of the jumpers. For details see chapter 2.8.
DC
Meter
SGND
RS485 (-)
RS485 (+)
Meter
SGND
RS485 (-)
RS485 (+)
Modem CDA70
Pin 1 – SGND
Pin 2 – SGND
Pin 3 – RS485 (-)
Pin 4 – RS485 (+)
Pin 5 – RS485 (-)
Pin 6 – RS485 (+)
Pin 7 – +12V EXT
Pin 8 – +12V EXT
+
1X
2X
1Y
2Y
OVPM-21
DC
Meter
SGND
RS485 (-)
RS485(+)
Meter
SGND
RS485 (-)
RS485(+)
Modem CDA70
Pin 1 – SGND
Pin 2 – SGND
Pin 3 – RS485 (-)
Pin 4 – RS485 (+)
Pin 5 – RS485 (-)
Pin 6 – RS485 (+)
Pin 7 – +12V EXT
Pin 8 – +12V EXT
+