810-1734-00 Rev A GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide
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Verification Gas
The verification gas certification is three (3) years and the cylinder holds enough gas for over 4 years
worth of verification runs based on the default ‘every three days’ sampling interval. It is important that
the gauge on the regulator be checked quarterly and a leak-check solution applied to fittings bi-
annually to insure no leaks have developed. The verification cylinder should be replaced when the
high pressure gauge reads less than 25psi (1.72 bar).
CAUTION: Use of verification gas that does not meet Siemens specifications will VOID
the GAS-Guard warranty.
Verification Gas Cylinder Removal and Replacement
WARNING: When full, the verification gas cylinder is pressured to greater than 500psi (34 bar).
Verification gas is regulated to 8psi (0.5 bar), nominal, before entering the GAS-Guard. Always
follow Compressed Gas Association (CGA) guidelines when handling and transporting
compressed gases.
The verification gas cylinder is used to automatically verify and calibrate the GAS-Guard. The cylinder
contains a certified NIST-traceable concentration of the eight-transformer fault gases measured by the
GAS-Guard.
1)
Turn off power to the GAS-Guard by opening the GAS-Guard door and toggling the power
switch located in the upper right hand corner to the OFF position.
2)
Turn the verification cylinder tank valve to the fully OFF (clockwise) position.
3)
Using a 9/16-in wrench loosen the verification cylinder to regulator union.
WARNING: A small amount of high-pressure verification gas will be released upon loosening
the fitting.
4)
While supporting the verification cylinder release the Velcro strap retaining the verification
cylinder in the bracket.
5)
Install the new verification cylinder into the mounting bracket and secure using the Velcro
strap.
6)
Connect the cylinder to the regulator union and tighten.
7)
Turn the knob on the top of the verification cylinder counterclockwise until it is fully open.
The regulator requires no pressure adjustment.
8)
Confirm that the bottle to regulator connection is leak-tight by applying a leak-check
solution to the fitting. Wipe away any excess leak-check solution.
Note: The leak check is very important, as even the smallest leak can substantially reduce the
life of the verification cylinder.