Rockwell Automation T7833 ICS Regent+Plus Math Package for Winternet - Manual (Page 12)

Math Package for W INTERPRET (T7833)
1 2
Industrial Control Services
Table 7. Error Codes.
Error Code Description Example
1 Underflow C = A / B; |A/B| < 1.175494E-38
2 Overflow C = A * B; A * B > 3.402823E38
C = A/B; B = 0
3 Not a number C = SQRT A; A < 0
4 Conversion AO = 3000 + 2000
(where AO is an analog output)
In most floating point equations, the results do not approach
the error limits of floating point math. When equations are
used that can produce floating point errors, the variable on
the left side of the equal sign will not be changed and it will
contain the last valid result. If under error conditions this
last value is not the best answer and a better answer can be
determined by the error code, then the error term should be
examined.
Example:
AO = 300 + AI
where,
AO is analog output (maximum 4095)
AI is analog input (0 - 4095)
if AI > 3795 then an error will occur.
Table 8. Example of Conversion Error, Error Code 4.
Scan AI AI+300 AO Comments
1 3000 3300 3300 No error
2 3200 3500 3500 No error
3 3700 4000 4000 No error
4 3900 4200 4000 Error Code 4, last value used
5 4000 4300 4000 Error Code 4, last value used
6 3780 4080 4080 No error
The most desirable answer for scans 4 and 5 would probably
be AO max = 4095, not the last value of 4000. To alter this
value, you may use the error code to examine the error term
to determine a better value.