Siemens SITRANS P500, Operating Instructions Manual, Page: 163 / 238

Operate
6.3 Description of the operating functions
SITRANS P500 with HART
Operating Instructions, 12/2014, A5E02344528-09
163
Example of an application
The current is to be measured as a voltage drop from 1 to 5 V at a resistance of 250 Ohm +/-
5%. To trim the tolerance of the resistance, set the current simulator so that the voltage drop
at 4 mA is exactly 1 V and at 20 mA is exactly 5 V.
● Trim at 4 mA:
Use the current transmitter trim menu option to instruct the pressure transmitter to output
4 mA. Read the measured value at an ammeter and input it. The pressure transmitter
uses this value for offset correction of the current.
● Trim at 20 mA:
Use the current transmitter trim menu option to instruct the pressure transmitter to output
20 mA. Read the measured value at an ammeter and input it. The pressure transmitter
uses this value for gradient correction of the current. The value for 4 mA is not affected by
this.
Note
If a multimeter is used, it must always be sufficiently accurate.
A Original characteristic
B Characteristic curve after current simulator trim 4 mA
C Characteristic curve after current simulator trim 20 mA
Figure 6-19 Current simulator trim
See also
"2.4.2.5 DA-Converter" (Page 106)