MKS Granville-Phillips Mini-Convectron 275 series, Инструкция по эксплуатации

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Chapter 4
40
Mini-Convectron Module with RS-485
Instruction Manual - 275545
Atmosphere Adjust
1. Allow the system pressure to rise to atmospheric pressure of air.
2. Use Table 4-1 to determine atmospheric pressure in torr for your area.
For sea level, send TS7.60E+02.
4.2 Use with Gases Other
Than N
2
and Air
Before using the Mini-Convectron gauge to measure the pressure of other
gases make certain the TS adjustment is correctly set for air.
It is important to understand that the indicated pressure on a
Mini-Convectron gauge depends on the type of gas in the tube, the gas
pressure in the tube, and on the orientation of the tube axis.
Mini-Convectron gauges are supplied calibrated for N
2
within the accuracy
of the instrument. With certain safety precautions, the Mini-Convectron
gauge may be used to measure pressure of other gases.
Mini-Convectron gauge tubes are thermal conductivity gauges of the Pirani
type. These gauges transduce gas pressure by measuring the heat loss from
a heated sensor wire maintained at constant temperature. For gases other
than N
2
and air, the heat loss is different at any given true pressure and thus
the indicated reading will be different.
Table 4-1 Altitude and Atmospheric Pressure
Altitude in feet
above sea level
Pressure in
Torr (N
2
or air)
Pressure in
mbar
0 760 1013.25
1000 733 977.25
2000 707 942.59
3000 681 907.23
4000 656 874.59
5000 632 842.60
6000 609 811.93
7000 586 781.27
8000 564 751.94
9000 543 723.94
10,000 523 697.27