User guide

eWON 500-2001-4001-4002 User Guide - IO Servers Configuration
eWON 500®2001®4001®4002® Version 4_3_0 - User Guide - 10/5/05 - ©ACT'L sa - Page 111
6.10.2.3.2 PT100 input AI5 and AI6
These two entries measure a Resistance value in Ohm.
As you can see, the slope is negative, and if you need to read the tag value converted in Ohm,
you can set a factor of -0.02014774 = -82.505/4095 with an offset of 162.13.
Figure 63: Tag’s configuration: reading the tag value in mA
If you need to convert in °C: temperature = AI * (-0.0394075) + 161.376.
The default range of PT100 in eWON is -50°C to 150°C.
Full range of ADC is: -52.92°C to 161.376°C (79.625 Ohm to 162.13 Ohm).
Note:
• eWON4002 prior to S/N 0517-xxxx-89 have a PT100 range from 0°C to 131.9°C and must apply the following formulas:
Ohm = IOValue * (-0.012402) + 150.8
°C = IOValue * (-0.0322) + 131.9
• eWON4002 from S/N 0517-xxxxx-89 to S/N 0521-xxxx-89 have a PT100 range from -56°C to 151°C
and must apply the following formulas:
Ohm = IOValue * (-0.0195068) + 158.2
°C = IOValue * (-0.050677) + 151.2
AI# Ohm
0 162.13
4095 79.625