Evaluating Temperature Channels - Siemens Sinamics S120 Function Manual

Monitoring and protective functions
8.5 Thermal motor protection
The calculated values from group 1 are available in the following parameters for
interconnection:
● r4112[1] = maximum
● r4113[1] = minimum
● r4114[1] = average value
NOTICE
Forming groups of temperature channels
Only form groups of continuously measuring temperature sensors. The switching
temperature sensors PTC and bimetallic NC contacts are only assigned two temperatures -
50°C and +250°C, depending on the state. Within a group with continuous temperature
actual values, the calculation of the maximum/minimum/average value temperature is
significantly falsified by taking into account switching temperature sensors.
8.5.11.4

Evaluating temperature channels

For each of the individual 12 temperature channels, an alarm threshold and a fault threshold
can be set in p4102[0...23]. The even parameter indices contain the alarm threshold and the
uneven parameter indices, the fault threshold. The temperature thresholds can be set
between -99°C and +251°C for each channel.
If the evaluation of the temperature actual value from p4105[0...11] exceeds the alarm
threshold set in p4102[0...23], then an alarm is output at r4104.0...23. Timer p4103[0...11] is
started at the same time.
If, after the timer has expired, the temperature actual value is still above the alarm threshold,
then an appropriate fault is output. This fault can be acknowledged as soon as the
temperature actual value is again below the alarm threshold.
If the evaluation of the temperature actual value from p4105[0...11] has exceeded the fault
threshold set in p4102[0...23], then the corresponding fault is immediately activated.
Using p4118[0...11], a hysteresis for p4102[0...23] can be set for each channel.
Using p4119[0...11], a filter can be activated to smooth the temperature signal for each
channel.
The time constant of the filter depends on the number of active temperature channels and
can be read in r4120.
Failure of a sensor
Using parameter p4117[0...2], the response to the failure of a temperature sensor can be set
within a group:
● p4117 = 0 is set. The failed sensor is not taken into account.
● p4117 = 1 is set. The group outputs the value -300 °C to the outputs for the maximum
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value, minimum value and the mean value.
Function Manual, (FH1), 01/2012, 6SL3097-4AB00-0BP2
Drive functions