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: 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.
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.
In the following cases a warning message is given:
-
One of the kp or dband parameters are negative. the function block uses the value 0 instead of 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).