Voltage Measurement - WAGO 750-489 Manual

94 Process Image
4.8

Voltage Measurement

Standard Format
In voltage measurements, the I/O module outputs the measured values as
a process value normalized to 25000.The defined measuring range of
−30 mV ... +30 mV for example corresponds to a possible process value of
−25000 ... +25000.
The voltage values are represented at a resolution that depends on the
measuring range:
• 1 digit per 0.0012 mV (±30 mV)
• 1 digit per 0.0024 mV (±60 mV)
• 1 digit per 0.0048 mV (±120 mV)
• 1 digit per 0.01 mV (±500 mV)
• 1 digit per 0.02 mV (±1000 mV)
• 1 digit per 0.04 mV (±2000 mV)
in one word (16 bits).
Voltage values below 0 mV are represented in binary form as the two's
complement. The voltage underranges and overranges relate to manufacturer
range violations.
S5-FB250 Format
For voltage measurements with S5-FB250 format enabled, the I/O module
outputs the measured values for the sensors normalized to 2500.
The defined measuring range of −30 mV ... +30 mV for example corresponds to a
possible process value of −2500 ... +2500.
Note:
Be aware that the status information is represented in bit 0 ... bit 2 and the
digitized measured value in bit 3 ... bit 15. Therefore, the normalized measured
value is shifted by three bits in the process image!
Thus a normalized measured value of +2500 corresponds to a process value of
+20000.
The voltage values are represented at a resolution that depends on the
measuring range:
• 1 digit per 0.012 mV (±30 mV)
• 1 digit per 0.024 mV (±60 mV)
• 1 digit per 0.048 mV (±120 mV)
• 1 digit per 0.1 mV (±500 mV)
• 1 digit per 0.2 mV (±1000 mV)
• 1 digit per 0.4 mV (±2000 mV)
in one word (16 bits).
Manual
Version 1.1.0, valid from FW Version 02
WAGO-I/O-SYSTEM 750
750-489 4AI RTD/TC/Strain Gauge Ex i