Servomex NanoTrace DF-760E, Инструкция по эксплуатации

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Service DF-760E 129
Calibration systems are supplied with a 3000 ppm-hr purifier. Replacement purifiers can
be ordered from Servomex.
NOTE
The gas purifier supplied by Servomex has a finite life that is
greatly affected by the source gas oxygen level, flow rate, and
duration of sampling. Always minimize the time sampling from the
purifier and ensure that the source gas is below 50 ppb for optimal
life expectancy.
9.3.7.1 Determining When to Change the Purifier
In time the active component in the purifier becomes depleted and oxygen breakthrough
occurs.
There are two observable signs of breakthrough:
1. When no decrease in the oxygen reading is noted after switching to zero gas. (This
assumes that the process gas contains some low level of oxygen.)
2. When the zero reference value increases after each successive zero calibration, see the
Troubleshooting section in this manual.
The following verification test lets you know if breakthrough is occurring, and that the
purifier needs to be replaced:
1. Establish a stable oxygen reading by diverting the low ppb process gas through the
gas purifier at a flow rate of 0.5 slpm.
2. Increase the flow rate to 2.0 slpm. If after several minutes, there is an increase in
the analyzer’s reading, replace the purifier.
9.3.7.2 Preparation for Gas Purifier Installation or Replacement
NOTE
Read the installation instruction and prepare all tools and parts for
a quick installation. The new purifier must be installed rapidly to
minimize exposing the purifier to ambient oxygen levels. Tools and
supplies must be readily available and all preparations to the
calibration system must be done before removing the new purifier
from its packaging.
Removal and installation requires the following tools and parts:

5/8 – inch open end wrench (for plumbing caps on initial installation)

1 3/8 -inch open end wrench (for purifier body)

3/4 -inch open end wrench (for VCR fitting on calibration panel)

Two VCR-type gaskets and retainers Servomex P/N 210431 or Cajon P/N
SS-4-VCR-2-GR