Thermal Shock Protection (Tss) - Siemens RWF50.3 User Manual


Interlocking
Function
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Building Technologies Division
Infrastructure & Cities Sector

5.7 Thermal shock protection (TSS)

Note!
Functions Cold start of plant and Thermal shock protection (TSS) are interlocked.
Only one function can be activated, but never both at the same time.
The controller comes with thermal shock protection (TSS) deactivated; it can be
activated at the configuration level.

Reference!
See chapter 8.3 Thermal shock protection (TSS) rAFC.
The function is automatically activated when the actual value drops below the
adjustable limit value rAL (exceeds the adjustable limit value with the cooling controller).
In that case, the setpoint is approached via a ramp function.
Gradient and slope of the ramp
symmetrical tolerance band toLP. If, during the startup phase, the actual value leaves
the tolerance band, the setpoint ramp is stopped until the actual value returns to a level
within the tolerance band. The startup phase is ended when the setpoint of the ramp
function reaches the final setpoint SP1.
Note!
When thermal shock protection (TSS) is active, the controller operates in low-fire
operation. The response threshold (q) is active.
Temperature
SP1
rAL
toLP
t1
t2
Figure 15: Thermal shock protection (TSS)
Key
Setpoint (w)
Actual value (x)
User Manual RWF50...
5 Operating modes
rASL
are adjustable. The setpoint ramp has a
t3 t4
t
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CC1U7866en
25.07.2014