Siemens SIMATIC S5 Manual page 324

Glossary
T
Z
U-batt
Watchdog
Wind-up effect
Zone control
9–8
Filter time for damping the influence of the derivative action.
Back-up voltage at the bus connector of the module to supply the
RAM memory if there is a power failure.
If the operating program of the IP 244 runs normally, a pulse signal
is generated. If this signal is not detected, an error has occurred in
the program.
If a manipulated variable is calculated which is greater than 100%,
the integration (I action) is interrupted to allow the controller to
ensure that the controller becomes effective quicker to adapt
the control variable to the setpoint.
The controller only operates within the specified control variable
range, specified by zone upper and zone lower limits relating to
the corresponding setpoint value. If the control variable is out of
range, the module operates with the manipulated variable
of + 100%, – 100% or 0%.
IP244
C79000–Y8576–C858–02