Step 5 Configure Setpoint Relays For The Application; Step 6 Calibrate The Convectron Gauge; Atmospheric Pressure Calibration; Vacuum Chamber Pressure Calibration - HELIX GRANVILLE-PHILLIPS Convectron ATM Instruction Manual

Atmospheric pressure
calibration
Vacuum chamber
pressure calibration
®
Convectron ATM Vacuum Gauge Module Instruction Manual
Step 5
Configure setpoint relays for the application
• To configure setpoint relays for the analog version of the module, see
pages 26–33.
• To configure setpoint relays for the RS–485 version of the module, see
pages 49–53.
If the module will measure the pressure of a gas other than N
must adjust relay setpoints for the process gas. The true pressure of a gas
other than N or air may be substantially different from the pressure that the
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output indicates. For example, outputs might indicate a pressure of 10 Torr
for argon, although the true pressure of the argon is 250 Torr. Such a
substantial difference between indicated pressure and true pressure can
cause overpressurization resulting in an explosion.
Failure to use accurate pressure conversion data for N
or air to other gases can cause an explosion due to
overpressurization.
If the module will measure any gas other than N
connecting relays to system control devices, adjust setpoints for
the process gas that will be used.
Step 6
Calibrate the Convectron gauge
Calibration improves the accuracy and repeatability of the Convectron
gauge.
• To calibrate the Convectron gauge for the analog version of the module,
see pages 34–37.
• To calibrate the Convectron gauge for the RS–485 version of the module,
see pages 56–57.
An atmospheric calibration is performed on the Convectron gauge, using
N , at the factory before the module is shipped. The factory calibration sets
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the atmospheric calibration point to 760 Torr of N
Because performance varies depending on the process gas, you may wish
to reset the atmospheric calibration point if a gas other than N
being used. Periodic resets of the atmospheric calibration point also
improve the accuracy and repeatability of the Convectron gauge near
atmospheric pressure, even if the process gas is N
Periodic resets of the vacuum chamber pressure calibration point improve
the accuracy and repeatability of the Convectron gauge.
WARNING
or air, before
2
.
2
or air.
2
Installation
or air, you
2
2
or air is
2
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