Siemens SIMATIC ET 200SP F-AI 4xI 0(4) 20mA 2-/4-wire HF Series - Page 31

Parameters/address space
4.3 Explanation of parameters
Analog input module F-AI 4xI 0(4)..20mA 2-/4-wire HF (6ES7136-6AA00-0CA1)
Manual, 08/2018, A5E41448857-AB
31
"Tolerance window %, relative" parameter
The tolerance window is calculated as a percentage of the
smoothed
process value that
represents the MIN or MAX value (depending on the parameter assignment of the standard
value) in this instant.
You can calculate the relative tolerance window using the following formula:
Calculate the maximum deviation of the current using the following formula:
With
● I
EW
= Process standard value (min./max.)
● I
MA
= 0 mA for measuring range 0 ... 20 mA
● I
MA
= 4 mA for measuring range 4 ... 20 mA
● T
rel
= Tolerance in %
● ΔI
rel
= Maximum deviation of current (+/-)
You can assign a value of 2.0 to 20.0% for the "Tolerance window %, relative" parameter for
each channel pair.
Figure 4-4 Relative deviation in % of the nominal range for measuring range 0 to 20 mA or 4 to 20 mA