56
Functions
WAGO-I/O-SYSTEM 750
753-668/000-004 4FAI 0/4-20 mA Diff PROFIsafe
Manual
Version 1.0.0, valid from HW/SW Version 01/01
Figure 14: Tolerance Window and Discrepancy Mode
– Minimum Unit Value
Tolerance settings are made via the “
Tolerance Window
” parameter, which is
described in Section “Commissioning” > … > “Setting Parameters”. The
parameters to be set and the formulas for calculation are listed below.
The following parameters must also be set:
•
Sensor evaluation
•
Relative tolerance and/or
•
Absolute tolerance
•
Discrepancy time
Formula for calculating the absolute tolerance from the process values:
∆𝑃𝑊
𝑎𝑏𝑠
= ±
(𝑃𝑊
𝑀𝐸
− 𝑃𝑊
𝑀𝐴
) ∗ 𝑇
𝑎𝑏𝑠
100
Factor
Value
PW
abs
Absolute tolerance of the process value
PW
MA
Process value for start of measurement range (depending
on measurement range and analog value data format)
PW
ME
Process value for end of measurement range (depending
on measurement range and analog value data format)
T
abs
Set absolute tolerance in %