MKS Stabil-Ion 370 Series, Инструкция по эксплуатации, Страница: 87 / 122

4 Preparing the Stabil-Ion System for Operation
4-29
Series 370 Stabil-Ion Instruction Manual - 370119
4.9 Adjustment of Convectron Gauge Zero and Atmospheric Pressure Indications
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 or the gauge becomes
contaminated and does not read correctly. 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
or Air pressure with any gauge when properly installed
with the gauge axis horizontal.
For accurate readout, the vacuum and atmosphere adjustments must be made in the following
order.
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 4-16) 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 gauge display A indicates the local
atmospheric pressure in the pressure units you have selected.
6. Repeat the above steps for Convectron Gauge B.
NOTE: 1 atmosphere normal at sea level = 7.6 x 10
2
Torr = 1.0 x 10
3
mbar = 1.0 x 10
5
Pa.
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 4.7.1 on page 4-19 before
using with other gases.
Figure 4-16 Control Unit Front Panel (with Door Open) Showing
Convectron Gauge Zero and Atmospheric Adjustments
O
I G 1
O
Degas
O
Power
O
I G 2
Data Port
IG1 L F1
N2 TORR
▲
▼
Cancel
Select
IG-1 AUTO
SET OFF
ATM
VAC
IG-2 AUTO
SET OFF
ATM
VAC
CONVECTRON ELECTROMETER Process Control RS-232
Off SP On
▲
▲
▲
▲
▲
▲
Off SP On
1
2
3
4
5
6
3
Set