DPS Telecom BVM 48 User Manual page 28

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Fig. 10.20
7. Log back into the unit and click User Analogs from the (blue) Monitor menu. Now you should be
able to view the live voltage reading.
6. High/Low Ref: Example, this temperature sensor
is a current loop sensor that outputs 4-20mA. The
BVM uses a 250 Ohm resistor to convert current to
voltage measurement. Ohms law says:
4mA X 250 Ohms = (0.004 X 250) = 1VDC
20mA X 250 Ohms = (0.020 X 250) = 5VDC
The documentation that came with this sensor
explains how 4 - 20 mA translates temperature. In
this case:
4mA (or 1VDC) = 32º F
20mA (or 5VDC) = 131º F
Therefore, my reference values are 1 = 32 and 5 =
131.
Fig. 10.21
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