Always use tubing that is free of oil and dirt. Stainless steel tubing is rec-
ommended.
Figure 3-8. Z-purge setup.
Z-Purge Connections
Connect instrument air to the sensor Z-purge inlet. Maintain the pressure
and flow as directed on the Z-purge warning label.
•
You must provide a protective gas supply with an alarm for a loss of
pressure indication in order to meet NFPA 496 requirements.
•
You must not exceed the maximum temperature rating listed in the
specifications.
•
Process pressure is assumed to always be subatmospheric (vacuum)
unless the High-pressure option is installed.
•
The WDG-IV sensor contains a flame arrestor to prevent it from being
an ignition source to the process for short periods of high combustible
levels (25% of LEL - lower explosive limit) in the process. The flame
arrestor is not, however, intended to protect the process where the
combustibles levels are always high.
Installation | 3-13