Use Of Internal Termination; Address Programming Methods; In The Test Network - Thies CLIMA Hygro-Thermo Transmitter-compact Instructions For Use Manual

6.5 Use of internal termination

The MODBUS sensors have internal DC termination with a resistance value of 135 Ohm. With the
sensors the termination can be activated by bridging Pin 3 and Pin 7 in the threaded bush of the
connecting cable.
Termination is recommended for the following applications:
- Single sensor operation with medium to long cable lengths or
- Operating the network with several sensors using the following parameters
- Pull resistances on cables D0 and D1 greater than 750 Ohm (in the master)
- Number of sensors in the network segment smaller than 10 with poll intervals > 1s
in total network.
To guarantee the accuracy of the measured values, the internal DC termination of sensors is not
recommended for other applications. In this case, the termination resistance needs to be spatially
separated due to heat build-up.
Note:
The interrogation frequency of all sensors in the network is relevant to termination resistance heat
build-up. For short cable lengths (up to 20m), termination can be dispensed with.

7 Address programming methods

7.1 In the test network

- Recommended during incoming goods inspection
- requires PC with RS-485 interface and MODBUS master software (e.g.: MODBUS Poll)
or a MODBUS master system.
PC
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