Cold Start Thermal Shock Protection (Cstp); Cstp - Modulating Operation - Siemens LMV5 Series Basic Documentation

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6.8 Cold start thermal shock protection (CSTP)

Thermal shock protection can be activated and deactivated.
A differentiation is made between modulating and multistage control.
The cold start sequence is activated when, on startup, the actual value lies below the
ON threshold).
If thermal shock protection is activated, the manipulated variable on cold start will be
increased in a stepwise fashion using the set load step (or the next stage will be
activated).
The output will be increased as soon as the actual value has exceeded the start value
of the load stage by the setpoint step.
If this switching threshold is not reached within the adjustable maximum time, heating
will automatically be ensured by the next output stage. When the OFF threshold is
reached, the cold start sequence will be terminated in order to switch to normal control
operation.
Parameters: Thermal shock protection on / off
Activation value for thermal shock protection
Deactivation value for thermal shock protection
Load step (only for modulating mode)
Setpoint step, modulating
Setpoint step, multistage
Max. time, modulating per step
Max. time, multistage per step

6.8.1 CSTP - modulating operation

For the output step, any output value in % can be predefined.
100 % divided by the output step gives the number of possible stages.
Setpoint
Spacing of temperature lines
corresponds to the setpoint steps
Output
steps
Burner off, Setpoint step not reached,
actual value but max. time exceeded.
below thresh- Therefore, manipulated
old ON. variable increased by
Burner will be output step
switched on
Basic Documentation LMV51...
6 Temperature or pressure controller (internal load controller LC)
Threshold OFF
Setpoint step is reached
before max. time has elapsed.
Manipulated variable increased
by output step
ColdStartOn
ThresholdOn
ThresholdOff
StageLoad
StageStep_Mod
StageStep_Stage
MaxTmeMod
MaxTmeStage
Actual value
Manipulated
variable
Threshold ON
Actual value reached.
⇒
Threshold OFF
Change to control
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01.10.2003