810-1734-00 Rev A GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide
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Turning the GAS-Guard On/Off
CAUTION: Always ensure helium is being supplied to the analyzer. Never leave the helium
inlet to the GAS-Guard exposed to atmosphere.
CAUTION
: The GAS-Guard is designed to operate continuously. When powering down the
GAS-Guard for extended periods of time (more than 24 hours), always close the oil supply and
return valves to the analyzer.
To isolate (shut off) the oil inlet and oil outlet ports, close the transformer oil supply and return valves
or close the Siemens manual DGA (sample port/oil shutoff) valve as well as the Siemens oil return
valve located on the bleed fixture.
The figure below is a typical example of one of these valves. There are at least two valves per
installation, one for the inlet and one for the outlet. The exact location and number of these valves will
vary by installation. The valve is shown in the ON position in the following figure.
Figure 2: Oil shut off valve
For whatever reason, if the GAS-Guard is consistently unable to complete its sample runs, Siemens
recommends powering down the GAS-Guard and closing the supply and return valves (described
above) until the exact nature of the problem is understood and/or corrected. This will ensure no
damage is caused to the GAS-Guard.