810-1734-00 Rev A GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide Table of Contents Introduction................................3 Product Symbols..............................4 Operation ..................................5 Calibration ................................5 Alarm Settings..............................5 New transformers or transformers with no previous gas data:................. 6 Transformers with a stable gassing history: ......................... 6 Gassing Transformers which have been degassed: .....................
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GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide 810-1734-00 Rev A Table of Tables Table 1: Product Symbols ............................4 Table 2: Recommended caution/alarm settings for transformers with no previous gas data.....6 Table 3: Recommended caution/alarm settings for transformers with a stable gassing history....6 Table 4: Recommended caution/alarm settings for gassing transformers after degassing......7...
GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide Introduction The Siemens GAS-Guard is an on-line laboratory-grade gas chromatograph. The GAS-Guard detects and measures fault gases found in the cooling oil of power transformers. The GAS-Guard is designed and constructed to operate under those environmental conditions typical of a power substation or generating facility.
GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide 810-1734-00 Rev A Product Symbols The following symbols are used throughout the GAS-Guard or accessories. They are defined by the International Electrotechnical Commission, IEC 878 and IEC 417A. It is important for safety reasons to have an understanding of their representation.
PPM in Gas’ graph in GAS-Guard View (Graph Tools→Maintenance→Verification Data). A manual recalibration should not be required unless a new certified verification cylinder is installed, approximately once every three years. If Siemens has connectivity to the GAS-Guard during the standard warranty period (12-months from date of shipment) Siemens will periodically confirm calibration of the GAS-Guard as well.
GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide 810-1734-00 Rev A New transformers or transformers with no previous gas data: Set the GAS-Guard caution level to 50% and the alarm level to 100% of the low-end CAUTION ppm limits proposed by IEEE PC57.104 Draft 11, published April 21, 2004; except acetylene, as noted below.
GAS-Guard to run for thirty (30) days to establish gassing trends and baseline measurements. After this data has been collected, you should consult with Siemens (support@serveron.com) to determine the appropriate caution and alarm settings for the transformer.
810-1734-00 Rev A Front panel lights (Indicators) The Siemens GAS-Guard has three colored lights (LED’s) located on the front panel. These lights are described in the following Table as they appear on the front panel, from top to bottom. Light...
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.
810-1734-00 Rev A Manual DGA Sampling A manual DGA sample port is installed in-line with the GAS-Guard oil supply tubing. Siemens recommends this port for correlation of GAS-Guard data to manual DGA data. The location of the sample port will vary by installation. The sample port provided with the GAS-Guard is a ¼-in locking valve with a 1/4-in FNPT fitting.
810-1734-00 Rev A GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide Maintenance The Siemens GAS-Guard has been designed to keep maintenance to a minimum. The following will help you determine the best service plan. Helium and Verification Gas Helium Gas The helium gas cylinder will last greater than four (4) years based on the default four hour sampling interval.
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GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide 810-1734-00 Rev A Carefully support the regulator to prevent any damage to the 1/8-in helium line or regulator. CAUTION: It is extremely important that no water or other foreign contaminates be allowed to enter the open regulator fitting or tubing.
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.
GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide 810-1734-00 Rev A For Serveron Monitoring Service users, please complete and return the Verification cylinder data sheet to Technical Support (support@serveron.com) after the Verification cylinder is replaced. Figure 4: Installed verification cylinder Leak Check Fittings After the first month of continuous use, all regulator, gas and oil fittings should be checked for leaks.
810-1734-00 Rev A GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide Oil Filter Service The GAS-Guard uses two inline screen type oil filters. Under normal operation, no filter maintenance is required. If service is require, the filter consist of three main parts: the filter housing, filter screen and the filter cap.
GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide 810-1734-00 Rev A Customer Replaceable Units (CRU’s) Customer Replaceable Units (CRU’s) are defined as customer replaceable parts onsite without decommissioning the GAS-Guard. Part # Description 270-0004-XX Helium Dryer 290-0020-XX Regulator, CAL,...
810-1734-00 Rev A GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide Return Shipping Instructions Prior to returning parts to Siemens a Return Material Authorization (RMA) number must be obtained from Siemens technical support: Technical Support: +1 (866) 273-7763 E-mail: support@serveron.com).
GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide 810-1734-00 Rev A Forms Verification Cylinder Data Sheet Upon successful installation of your verification cylinder; please complete and fax or e- mail this Verification Cylinder Data Sheet to Technical Support at: +1 (503) 924-3290 fax or support@serveron.com e-mail...