8.3 Remote Calibration
Figure 15 PrimaX with CalGard
The CalGard stainless steel remote calibration adaptor provides reliable operation of remotely installed gas
detectors working under harsh environmental conditions. Additionally, the CalGard allows remote verification
("bump test") or instrument calibration of gases listed later in this section and oxygen via a hose connection
in the presence of wind speeds up to 6 m/s.
In normal measurement operation, the ambient air passes through the air vents into the remote calibrator
directly to the sensor (diffusion operation). During a bump test or instrument calibration, the test gas is
supplied to the sensor via the hose connection at the bottom of the CalGard. An integrated mechanism
prevents the dilution and dispersion of test gas otherwise caused by external influences, such as wind. This
allows a fast response from the sensor to the applied test gas.
Once calibration is complete, the air inlet reopens to allow the monitoring of ambient air for gas without the
need for further user intervention.
8.3.1 Installation
For correct operation, PrimaX and CalGard must be used in a vertical position (hose connection pointing
downwards). The CalGard remote calibration adaptor can be attached to the sensor by screwing on the
thread of the detector.
The tube connector is adapted for tubes with an inner diameter of 5mm.
In general the hose should be as short as possible in order to:
• Minimise the gas volume needed to flush the tube
• Reduce external influences (e.g. temperature shift, pressure, etc.)
• Minimise the lead time
Hose material should be adapted to the applied test gas, have no absorptive or adsorptive properties and
should be made from inert material such as teflon or polyethylene.
When using the CalGard in the hazardous area, a conductive hose must be used.
GB PrimaX 54
8 Accessories
To Next Page
Loading...
