Series 360, Granville-Phillips, Stabil-Ion, Ionization, Vacuum ...

4 Preparing the Stabil-Ion System for Operation
4.9 Adjustment of Convectron Gauge Zero and Atmospheric Pressure Indications
Using the N 2 calibration to pressurize a vacuum system above about 1 Torr
with certain other gases can cause dangerously high pressures which may
cause explosion of the system. See Section 4.6.1 on page 4-12 before
using with other gases.
Each Convectron Gauge is individually computer calibrated for N 2 . Adjustment of the zero should
not be necessary unless readout accuracy is required below 1 x 10 -3 Torr. Adjustment of the
atmospheric indication should not be necessary unless compensating for long cables or variations
in mounting orientation. The Convectron Gauge has a stable, temperature compensated design and
each controller is also calibrated to provide accurate readout of N 2 pressure with any gauge when
properly installed with the gauge axis horizontal.
RS-232
ELECTROMETER
CONVECTRON
IG-1 AUTO
PROCESS CONTROL
Off SP On
Data Port
IG2 Scale
IG1
Factor
Adjust
Pressure
Range
L HL H
Cathode
1 21 2
IG1 IG2
OFF SET
ATM
VAC
IG-2 AUTO
OFF SET
ATM
VAC
1
2
3
4
5
6
3
▲
Set
▲
C
H
A
N
N
E
L
IG1
O
Degas
O
IG2
O
On
O
Remote
Figure 4-20
Control Unit Front Panel (with Door Open) Showing Convectron Gauge
Zero and Atmospheric Adjustments.
1. Evacuate Convectron Gauge A to a pressure known to be less than 1x10 -4 Torr.
2. With power on and at vacuum less than 1 x 10 -4 Torr for at least 15 minutes, adjust VAC for
gauge A (see Figure 4-20) until display A indicates 0.0 0 Torr/mbar or 0.0 0 Pa, not 1.0 -4,
1.0 -2, or 0.0 -0.
3. Let the pressure in the gauge increase to the local atmospheric pressure.
4. Read the local atmospheric pressure on an accurate barometer nearby.
5. With the power on, adjust ATM adjustment A until display A indicates the local atmospheric
pressure in the pressure units you have selected.
6. Repeat the above steps for Convectron Gauge B.
Series 360 Stabil-Ion December, 2001
4-24