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APPENDIX D – ANALOG OUTPUTS (IF EQUIPPED)
If the instrument is equipped with the analog output option, there will be a five-
pin connector on the bottom of the instrument. Also, an analog output cable will
be included with the instrument. This cable will have a five-pin connector on
one end and four tinned wires on the other end.
The instrument will output a Voltage between 0 and 5 Volts that corresponds to
the Air Velocity measured by the instrument. The output range, pin
assignments, and wire colors are given in the table below. Also shown is a
block diagram of the analog output circuit.
Corresponding
Wire
Analog
Output
Measurement
Equation* to convert
from
Color
Pin
#
Function
Voltage
Range
Range
Volts (
V
) to Measurement
Value
BLK
1
Ground
--- N/A ---
--- N/A ---
--- N/A ---
GRN
2
Air Velocity
0 to 5
Volts
0 to 10,000
FPM
Air Velocity = 2000×
V
GRY
3
--- Not Used --- --- N/A ---
--- N/A ---
--- N/A ---
WHT
4
--- Not Used --- --- N/A ---
--- N/A ---
--- N/A ---
*To convert from Volts to Air Velocity in Feet per Minute, multiply by 2000.
►
For example, an analog output of 2.375 Volts means that the instrument is
measuring an air velocity of 4750 feet per minute (FPM).
► 2.375 Volts
×
2000 = 4750 FPM
Note:
When using analog outputs, there is an
additional ±1% error
in the
analog output voltage. This is in addition to the normal measurement error.
►
For example, an air velocity reading of 500 FPM would normally have an
accuracy of ±1% of reading ±1 digit (±6 FPM) when the data is viewed
on the LCD display.
►
With the additional error associated with the analog output voltage, the
effective accuracy of the analog output for this air velocity measurement
will be ±2% of reading ±1 digit (±11 FPM).
Custom Analog Voltage Outputs are also available – contact Omega for details.