1MRS755225
Transformer Terminal
Technical Reference Manual, General
RET 54_
51
5.1.9.
RTD/analog inputs
The RET 541 and RET 543 transformer terminals equipped with an RTD/analog
module (RTD1) have eight general purpose analog inputs for DC measurement. The
RTD/analog inputs are galvanically isolated from the transformer terminal power
supply and enclosure. However, the inputs share a common ground.
For technical data of the RTD/analog inputs, refer to Table 5.2.1-4 on page 91.
The parameters for the RTD/analog inputs are included in the parameter lists on the
CD-ROM “Technical Descriptions of Functions” (see “Related documents” on
page 9).
5.1.9.1.
Selection of input signal type
The general purpose RTD/analog inputs accept voltage-, current- or resistance-type
signals. The inputs are configured for a particular type of input signal by means of
the channel-specific “Input mode” parameters that can be found in the menu
Configuration/RTD1/Input #
. The default value is “Off” which means that
the channel is not sampled at all, and the IN+, IN- and SHUNT terminals are at high
impedance state.
1) Two-wire measurement
2) Three-wire measurement
5.1.9.2.
Selection of input signal range
For each measuring mode, a separate parameter is provided for choosing between
the available measurement ranges. These channel-specific parameters, which can be
found in the menu
Configuration/RTD1/Input #
, are named “Voltage
range”, “Current range”, “Resistance range” and “Temperature range”. All range
parameters can be set but only one is used. The value of the “Input mode” parameter
determines which range parameter is used. The “Temperature range” parameter also
defines the sensor type to be used, e.g. PT100.
RET 541/RET 543 + RTD1
RTD/analog inputs
RTD1_6_AI1
RTD1_6_AI2
RTD1_6_AI3
RTD1_6_AI4
RTD1_6_AI5
RTD1_6_AI6
RTD1_6_AI7
RTD1_6_AI8
Parameter
Values
Default
Input mode
0 = Off
Off
1 = Voltage
2 = Current
3 = Resistance 2W
1)
4 = Resistance 3W
2)
5 = Temperature 2W
1)
6 = Temperature 3W
2)
