Format - Siemens Metro 21 M216KA Operator's Manual

Reference
Junction
Reference Junction
None The module records only the temperature difference between the measurement point and the
free ends of the thermocouple.
Dynamic reference Connect a platinum resistance thermometer to the resistance measurement module on slot A
temperature module in order to record the reference junction in the climatic temperature range. Any thermocouple
on A types on the remaining slots can then use this reference temperature.
ET 200L-SC and Smart Connect: The reference temperature refers to slot A on the TB16SC
and applies to all other SC modules.
ET 200L-SC IM-SC and Smart Connect: The reference temperature refers to slot A on the
TB 16IM-SC and applies to all other SC modules. Slot A of the TB16 SC cannot generate a
reference temperature.
Dynamic reference Select this option if the temperature at your reference junction is constant or the temperature
1
temperature at the reference junction is recorded by another module. You can specify the temperature in
the reference temperature parameter and adjust it dynamically in RUN mode.
1
In the case of the ET 200L-SC, the dynamic reference temperature is only possible with S7 masters.
Reference
Temperature
Interference
Frequency
Suppression
Smoothing

Format

ET 200L, ET 200L-SC and ET 200L-SC IM-SC Distributed I/O Device
EWA 4NEB 780 6009-02c
If you have connected a thermocouple, the following options are available to
you for specifying the reference junction:
Here you can enter the reference junction temperature in the climatic temper-
ature range for recording temperatures using thermocouples (in S7 number
o
format: 0.01 C and in S5 number format: 0.05
You can update this parameter using your application program.
You can, for instance, record the reference junction temperature via another
module.
In the case of the ET 200L-SC or ET 200L-SC IM-SC, entering the reference
temperature is only possible with S7 masters.
The frequency of your AC power supply can interfere with the measured
value particularly in the case of low voltage ranges and thermocouples. Enter
the mains frequency of your system.
The various measured values are smoothed by digital filtering. You can
choose between no, weak, medium and strong smoothing for each module.
The stronger the smoothing, the greater the time constant of the filter.
The analog input module supplies its information in S5 or S7 number format,
depending the parameterization.
SC Analog Electronic Modules – Parameters
Notes
o
C).
11-5