LORD V-Link-200, Руководство пользователя

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V-Link
®
-200
User Manual
7.2.2 Differential Input Gain and Offset
The combination of the gain, offset, and sensor signal cannot exceed the 0 to 5 V dc input of the
analog to digital converter within the node.
Resolution: Applying gain to the sensor signal can be used to maximize the measurement
resolution. The more of the range that is used, the more digital counts are available to measure
the signal, which typically means higher resolution measurements. Limitations to the gain
adjustment are the sensor's measurement capabilities and the 0 to 5 V input range of the node.
The signal produced after gain is applied to the sensor at full scale must not exceed the input
range of the node.
Offset Scale: The scale setting positions the no-load measurement of the connected sensor
within the 0 to 5 V range of the node input. The range of A/D counts that corresponds with the 0
to 5 V node input depends on the resolution of the node. An 18-bit node will have a full scale bit
range of 262144. A mid-range setting positions the baseline offset in the middle of the range (2.5
V or full scale bits*1/2) and is used for sensors with negative and positive going signals. The low-
range setting positions the baseline offset in the bottom quarter range (1.25 V or full scale
bits*1/4) and is used for sensors with mostly positive going signals. The high- range setting
positions the baseline offset in the top quarter of the range (3.75 V or full scale bits *3/4) and is
used for mostly negative going signals.
Figure 54 - Differential Input Resolution and Offset (18-bit Node)
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