Micro Motion 2200S, Руководство по конфигурации и использованию

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Configuration and Use Manual 27
Getting Ready to Configure
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Figure 3-1 illustrates the mA measurement point options. As shown:
• If your installation does not include the Micro Motion adapter-barrier, always use 12–20 mA. .
• If your installation does include the Micro Motion adapter-barrier, be sure you know the
location of the measurement device and set the mA measurement point appropriately:
- If the mA measurement device is between the transmitter and the adapter-barrier, use
12–20 mA.
- If the mA measurement device is between the adapter-barrier and the host, use 4–20 mA.
• If you don’t know how to set the mA measurement point, specify Don’t Know. The
Communicator and ProLink II will display data for both output scales.
Figure 3-1 mA measurement point options
3.4.2 Converting between mA output scales
Equations for converting between mA output scales are shown in Table 3-1.
Table 3-1 mA output scale conversion equations
Conversion Equation
12–20 mA to 4–20 mA • X = value on the 4–20 mA scale
• Y = value on the 12–20 mA scale
4–20 mA to 12–20 mA • X = value on the 4–20 mA scale
• Y = value on the 12–20 mA scale
12–20 mA
12–20 mA 4–20 mA
Micro Motion adapter-barrier
DCS
DCS
X Y 10 –
( )
2
×
=
Y
X
2
---- 10 + =