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Wire
Color
BLK
GRN
GRY
WHT
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, Temperature, and Humidity 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
Analog Output
Measurement
Equation* to convert from
Pin#
Function
Ground
2
AirVelocit
3
% Relative Humidit
0 to 5 Volts
Oto 100%RH
4
Tern erature
0 to 5 Volts
-20
°
C to 80
°
C
Tern erature [
0
C] =
20xV
- 20
*To convert from Volts to Air Velocity in Feet per Minute, multiply by 2000.
►
For example, an analog output of2.375 Volts on the green wire means that
the instrument is measuring an air velocity of 4750 feet per minute
(FPM).
►
2.375 Volts x 2000 = 4750
FPM
*To convert from Volts to Percent Relative Humidity
(%RH),
multiply by 20.
► For example, an analog output of3.722 Volts on the gray wire means that
the instrument is measuring a relative humidity of74.44
%RH.
► 3.722 Volts x 20 = 74.44
%RH
*To convert from Volts to Temperature in degrees Celsius (
°
C), multiply by 20
and subtract 20.
►
For example, an analog output of 3.458 Volts on the white wire means that
the instrument is measuring a temperature of 49.16 °C.
►
3.458 Volts x 20- 20 = 49.16 °C
Rev 1.8, 1 0-Jun-2008
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