Vaisala Drycap DMT152, User Manual

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Figure 6 Nokeval 301 Loop-Powered Display
1 3
4 2
DMT152
Analog connector
4 ... 20 mA output
4 Ch2+ (black)
2 Ch1+ (white)
3 GND (blue)
1 VDC+ (brown)
Power supply
21 ... 28 VDC
301/302 Nokeval
-
+
1
2
mA+
mA-
301/302 Nokeval
1
2
mA+
mA-
Figure 7 DMT152 Nokeval 301/302 Wiring Diagram
4.5 Sampling from Process
Sampling is needed when direct measurement of the air or gas is not possible or desirable.
This may be related to, for example, a high process temperature, protecting the sensor from
water spikes, the need to easily detach the instrument from a pressurized process without
running the whole process down, or wanting to make the measurement at a more convenient
location. To get a representative sample of the process gas and avoid error sources caused by
the sampling system, the following aspects should be considered:
DMT152 User Guide M210865EN-J
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