Instrutech The Hornet IGM402 User Manual page 48

Instruction Manual
The non-linear S-curve is convenient if you are replacing a Granville-Phillips
and you do not want to change anything in the control system. For new systems, however, the formulas needed
to interpret the non-linear signal are complex and difficult to use. The log-linear signal is generally easier to
interface with today's data acquisition and control systems.
Non-Linear Output
Granville-Phillips first Convectron
®
non-linear output signal of 0.375 to 5.659 Vdc for 0 to 1000 Torr
of N , roughly in the shape of an "S" curve, as shown at right. GP
2
adopted the same output curve for most of their Mini-
Convectron modules and controllers with non-linear output.
®
(though in recent years, some GP controllers produced a different
S-curve)
The non-linear output from InstruTech convection gauges,
modules, and controllers duplicates exactly the original S-curve of
0.375 to 5.659 Vdc for 0 to 1000 Torr.
Non-Linear Analog Output Non-Linear Analog Output
6 6 6
Output - Volts Output - Volts Output - Volts
5 5 5
4 4 4
3 3 3
2 2 2
1 1 1
-3 -3 -3
10 10 10 10 10 10
InstruTech
gauge controllers produced a
®
Pressure - Torr Pressure - Torr Pressure - Torr
-2 -2 -2 -1 -1 -1 0 0 0 +1 +1 +1 +2 +2 +2
10 10 10 10 10 10 10 10 10 10 10 10
Pressure (Torr)
+3 +3 +3
10 10 10
IGM402 Hornet
Convectron which has that output,
® ®
Non-Linear Analog Output
(N /air only)
2
Voltage
0.0000 0.3751
1.0E-04 0.3759
2.0E-04 0.3768
5.0E-04 0.3795
1.0E-03 0.3840
2.0E-03 0.3927
5.0E-03 0.4174
1.0E-02 0.4555
2.0E-02 0.5226
5.0E-02 0.6819
1.0E-01 0.8780
2.0E-01 1.1552
5.0E-01 1.6833
1.0E+00 2.2168
2.0E+00 2.8418
5.0E+00 3.6753
1.0E+01 4.2056
2.0E+01 4.5766
5.0E+01 4.8464
1.0E+02 4.9449
2.0E+02 5.0190
3.0E+02 5.1111
4.0E+02 5.2236
5.0E+02 5.3294
6.0E+02 5.4194
7.0E+02 5.4949
7.6E+02 5.5340
8.0E+02 5.5581
9.0E+02 5.6141
1.0E+03 5.6593
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