6. Commissioning, operation
6.4 Switching functions
Hysteresis function
GB
If the temperature fluctuates around the set point, the hysteresis keeps
the switching status of the outputs stable. With increasing temperature,
the output switches when reaching the switch point (SP).
Contact normally open (HNO): active
■
Contact normally closed (HNC): inactive
■
With temperature falling again, the output will not switch back before
the reset point (RP) is reached.
Contact normally open (HNO): inactive
■
Contact normally closed (HNC): active
■
Window function
The window function allows for the control of a defined range.
When the temperature is between window High (FH) and window Low
(FL), the output switches on.
Contact normally open (FNO): active
■
Contact normally closed (FNC): inactive
■
When the temperature is outside window High (FH) and window Low
(FL), the output does not switch on.
Contact normally open (FNO): inactive
■
Contact normally closed (FNC): active
■
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WIKA operating instructions temperature switch model TSD-30
Fig.: Hysteresis function
Fig.: Window function