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6.4.4 Electrical data interface CL0 (CS)
The electrical interface CL0 (galvanically de-coupled) is found at the additional terminal
under the sealable terminal cover (see Figure 3 on page 8).
The CL0 interface conforms to DIN 66348, Part 1. It is a passive two wire interface, i.e.
possesses no own power source. Data is transmitted as mark/space at a nominal current
of 20 mA. For that reason, it is also called a 20 mA current interface.
The voltage drop of the series switched transmitters and receiver in the meter is about
4 V. Thus a maximum of four meter outputs can be switched in series and operated by
one modem. The meters can be addressed and called up specifically. The CL0 interface
can be used for data transmission up to 1,000 m.
General features
Number of connected meters
4
Maximum cable length
up to 1,000 m
Data transmission rate
300 ... 9600 baud
Electrical features
Signal
one
zero
Sender
11 mA
≤ 2.5 mA
Receiver
9 mA
≤ 3 mA
Permitted voltage drops
Sender
max. 2 V
Receiver
max. 3 V
Maximum values
Current
30 mA (short circuit)
Voltage
30 V (open current circuit)
Table 5: Specifications of CL0
6.4.5 raconet radio interface
The raconet radio interface enables a wireless bi-directional communication like data
readout and transmission of commands between meter and data collector.
The data transmission takes places with 868 MHz in the licence free and regulated ISM-
Band.
The antenna of the radio interface can be designed as integrated antenna or as housing
antenna.
Further information for raconet readout system you can find in separately documents.
