Convection Gauge Analog Output - Log-Linear - Instrutech The Hornet IGM402 User Manual

Instruction Manual

Convection gauge analog output - LOG-LINEAR

6.3
ANALOG TYPE in SETUP CG1 or SETUP CG2 sub menu of SETUP CGS menu is set to LOG-LINEAR.
1 to 8 Vdc, 1 V/decade (N
This setting provides a log-linear analog output for convection gauges 1 and 2. The analog output is
proportional to pressure measurements from either of the convection gauges 1 or 2 as described below:
A) The log-linear output signal and pressure are related by the following
formulas when units of measurement is in Torr and mbar:
(volts – 5)
P = 10
Where P is the pressure in Torr or mbar, and V is the output signal in volts.
B) The log-linear output signal and pressure are related by the following
formulas when units of measurement is in pascals:
(volts – 3)
P = 10
Where P is the pressure in pascals, and V is the output signal in volts.
The following chart shows the graphical results of table and formulas
above for pressure measurements in Torr. Pressure is plotted on the X- axis
with a log scale; the output signal is plotted on the Y-axis on a linear scale.
9.000
8.000
7.000
6.000
5.000
4.000
3.000
2.000
1.000
0.000
1.0E-04 1.0E-03
InstruTech
/air only)
2
V = log (P) + 5
10
V = log (P) + 3
10
Log-Linear Analog Voltage to Pressure
1.0E-02 1.0E-01 1.0E+00
Pressure (Torr)
1.0E+01 1.0E+02 1.0E+03
IGM402 Hornet
Log-Linear Analog Output
(N /air only)
2
Pressure
(Torr) Voltage
1.0E-04 1.000
2.0E-04 1.301
5.0E-04 1.699
1.0E-03 2.000
2.0E-03 2.301
5.0E-03 2.699
1.0E-02 3.000
2.0E-02 3.301
5.0E-02 3.699
1.0E-01 4.000
2.0E-01 4.301
5.0E-01 4.699
1.0E+00 5.000
2.0E+00 5.301
5.0E+00 5.699
1.0E+01 6.000
2.0E+01 6.301
5.0E+01 6.699
1.0E+02 7.000
2.0E+02 7.301
3.0E+02 7.477
4.0E+02 7.602
5.0E+02 7.699
6.0E+02 7.778
7.0E+02 7.845
7.6E+02 7.881
8.0E+02 7.903
9.0E+02 7.954
1.0E+03 8.000
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