The bits of the status words have the following meaning:
Bit
|
Description
|
Bit 0 = 1
|
Error in a calculation in floating point values
|
Bit 1 = 1
|
Recording of an invalid value on one of the floating point value inputs
|
Bit 2 = 1
|
Division by zero during a floating point value calculation
|
Bit 3 = 1
|
Capacity overflow during a floating point value calculation
|
Bit 4 = 1
|
The following error will be shown:
-
One of the following variables is negative: inc_rate, dec_rate.
For calculation, the function block uses the value 0.
-
The parameter Outbias lies out of the area  .
In this case the function block uses a capped value:  or  .
|
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)
|
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 the 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 signaled if a non floating value is detected at an input or if there is a problem with a floating point calculation. In these cases the OUT, OUTD and MA_O outputs remain unchanged.
In the following cases a warning message is given:
-
The parameter inc_rate is negative: in this case the function block uses the value 0 in place of the faulty value from inc_rate.
-
The parameter dec_rate is negative: in this case the function block uses the value 0 in place of the faulty value from dec_rate.
-
The parameter outbias lies outside the area [(out_min – out_max), (out_max – out_min)]. In this case for calculating the value the function block uses (out_min - out_max) or (out_max - out_min).