Runtime error
Original instructions
Status word
The following messages are displayed in the status word:
Bit
Description
Bit 4 = 1
The following behavior is displayed:
  • The SP input lies outside the area [pv_inf, pv_sup]: for calculation the function block requires the values pv_inf or pv_sup.
  • The kp or dband parameter is negative. the function block uses the value 0 outside the incorrect parameter value.
  • The outbias parameter lies outside the area [(out_inf - out_sup), (out_sup - out_inf)]. For calculation, the function block uses the value (out_inf - out_sup) or (out_sup - out_inf).
Bit 5 = 1
The output OUT has reached the lower threshold out_min (see Note)
Bit 6 = 1
The output OUT has reached the upper threshold out_max (see Note)
Bit 7 = 1
The thresholds pv_inf and pv_sup are identical.
If an error occurs during floating point processing, it will also be displayed on the Statusoutput. For the list of possible floating point error codes, see Common Floating Point Errors.
Note on output OUT
NOTE: In manual mode these bits stay at 1 for only one program cycle. When the user enters a value for OUT which exceeds one of these thresholds, the function block sets the Bit 5 or 6 to 1 and blocks them from the user entered value. With the following execution of the function block the value of OUT no longer lies outside the area and the Bits 5 and 6 are set to 0 again.
Error message
An error is displayed when a non-floating point is recorded at an input, when a problem occurs during a calculation with floating points or when the limit values pv_inf and pv_sup are identical. The outputs OUT, OUTD, MA_O and DEV remain unchanged.
NOTE: For a list of all block error codes and values, see Controller.
Warning Message
In the following cases a warning message is given: