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EC6ST - 6 PORT CALIBRATION SYSTEM
Features & benefits
• Enables manufacturers to comply with quality standards such as ISO 9000
• Calibration from 1000 mbar to 10-6 mbar by direct comparison with
master reference gauges, traceable to national standards
• Simple operation
• Simultaneous calibration of a number of gauges
• Fitted with baking facility to reduce cycle times
BOC Edwards gauge calibration systems are designed to enable gauge users to comply with quality standards, such as ISO 9000, which areincreasingly specified by commercial, military and government establishments.
These standards call for regular calibration of measuring equipment used in production processes. Most vacuum processes are carried out within the pressure range 1000 mbar to 10-6 mbar and the instruments most frequently requiring calibration are capsule gauges, thermal conductivity types (for example, Pirani and thermocouple gauges), magnetron and hot cathode ionization gauges |
The calibration system consists of a six-port chamber fitted with a liquid
nitrogen cold trap. The chamber can be isolated from the turbomolecular pump by means of a manually operated isolation valve.
The chamber is ‘roughed’ by a rotary pump which is connected to the chamber through an electrically activated valve. When the pump is not ‘roughing’ the chamber it is used as a ‘backing’ pump for the turbo. Calibration gas is admitted into the system through a narrow pipe, discharging gas onto the domed top of the chamber. The flow of gas is controlled by a manually operated fine-control needle valve, to which the gassupply is connected.
Calibration is performed by connecting the test gauges to the chamber and evacuating it to a base pressure at least a decade and a half below the lowest point to be calibrated. The calibration gas inlet valve is then used to increase the pressure, noting readings on the test gauge compared to that of the reference master gauge. |
