Gas Guard 3Online dissolved gas analysis sensor

usa.siemens.com/assetservices

The Siemens GAS-Guard® family of products offers transformer owners advanced field-based dissolved gas analysis (DGA). DGA is the single-most comprehensive tool for transformer condition assessment. As transformers age, they endure various stresses that can contribute to a variety of failure mechanisms. Whether applied on a new or older transformer, appropriate online DGA monitoring and diagnostic tools can help utilities avoid unplanned failures, lower maintenance costs and extend transformer useful life.

GAS-Guard 3 is designed for straightforward installation and requires very little maintenance. Customers can individually program one caution and one alarm set point for the level (ppm) as well as rate of change (ppm/day) measurements of each gas. Additionally, the system incorporates one programmable alarm level relay contact closure and a status relay contact closure. GAS-Guard 3 can store up to two years of data in memory and can communicate the data through many major communication protocols including TCP/IP, DNP3 and Modbus (RTU and ASCII).

Gas Accuracy1 Repeatability2 Range3

Hydrogen H2 +/- 5% or +/- 2 ppm <2% 2-3,000 ppm

Oxygen O2 +/- 5% or +30 / - 0 ppm <1% 30-5,000 ppm

Methane CH4 +/- 5% or +/- 10 ppm <1% 10-5,000 ppm

Carbon Monoxide CO +/- 5% or +/- 3 ppm <1% 3-10,000 ppm

Carbon Dioxide CO2 +/- 5% or +/- 5 ppm <1% 5-30,000 ppm

Ethylene C2H4 +/- 5% or +/- 3 ppm <1% 3-5,000 ppm

Ethane C2H6 +/- 5% or +/- 5 ppm <1% 5-5,000 ppm

Acetylene C2H2 +/- 5% or +/- 1 ppm <2% 1-3,000 ppm

NOTES: All specifications are independent of oil temperature and gas pressure level.1 Percent of ppm - whichever is greater2 At gas calibration level3 Gas-in-oil

DGA tolerances of the GAS-Guard 8

Accuracy is commensurate with traditional lab results. The sensor continually collects oil samples as often as every two hours. GAS-Guard 3 can also measure moisture in the oil, oil temperature and ambient temperature. DGA results and other measurement data are time/date stamped and can thus be correlated to transformer load.

The software package included with GAS-Guard 3 sensor allows the user to graphically display continuous gas evolution for each of the three critical fault gases as well as moisture, load and ambient temperature. The software package also allows the user to trace changes in fault severity over time through dynamic plots created using the Duval Triangle and Rogers Ratios analysis tools.

Online DGA data populating diagnostic tools deliver new insights. This displays Rogers Ratios (IEEE PC57.104.D11d) and basic gas ratios (IEC 60599-1999-03).

The Duval Triangle (IEC 60599-199-03) provides a diagnostic outcome for combinations of three fault gases.

The Siemens GAS-Guard 3 provides accurate and repeatable measurement of three critical fault gases found in transformer oil.

Comprehensive data requires powerful analytical tools

GAS-Guard 3: Facts and figures

Moisture-in-oil and oil temperature option

Parameter Accuracy1 Range

Moisture-in-oil ±2% 0 – 100% RS2

<10% of reading for oil temperature >30° C

0 to 803 ppm

<18% of reading for oil temperature <30° C

0 to 803 ppm

Oil temperature ±0.1° C (typ.) -40° C to +180° C1 Includes nonlinearity and repeatability2 Relative saturation3 Upper range limited to saturation

Environmental specifications

Operating temperature –50° C to + 55° C

Cold-start temperature –20° C

Operating humidity 5% to 95%, RH noncondensing

Oil inlet pressure 0 to 45 psi, to 3 bar

Storage temperature –40° C to +75° C

Storage humidity 5% to 95%, RH noncondensing

Physical specifications and weights

Height 22.0 in (55.9 cm)

Width 20.0 in (50.8 cm)

Depth 11.2 in (28.4 cm)

Weight 65 lb (29.5 kg)

Enclosure rating IP 66, NEMA 4

Packaged dimensions 26.4 in x 26.4 in x 15.9 in (67 cm x 67 cm x 40.3 cm)

Shipping weight (monitor only) 70 lb (31.8 kg)

Certifications/standards

Electromagnetic compatibility

Specification Test method

EN 61326 Class A: 2002 EN 61326: 2002 radiated emissions,

2002 conducted

emissions

EN 61000-3-2: 2000 EN 61000-3-2: 2000 current harmonics

EN 61000-3-3: 2001 EN 61000-3-3: 2001 voltage

fluctuations

EN 61326 Annex A: 2002 IEC 61000-4-2: 2001 ESD

IEC 61000-4-3: 2002 radiated immunity

against HF field

IEC 61000-4-4: 2004 EFT

IEC 61000-4-5: 2001 surge

IEC 61000-4-6: 2004 conducted RF

immunity

IEC 61000-4-8: 2001 magnetic field

immunity

IEC 61000-4-11: 2004 voltage dips and

interrupts

Safety

IEC 61010-1, IEC 61010-2-81

UL 61010-1 (2nd Edition), UL 60950-1 Clause 6.4

CSA-C22.2 No. 61010-1-04

Input power requirements

Voltage 115 VAC or 230 VAC ±15%

Frequency 50/60 Hz

Current 6 A maximum at 115 V

3 A maximum at 230 V

Gas analysis

Oil sampling is continuous and gas analysis intervals are user-selectable from 2 hours to 12 hours (Default: 4 hours)

All data is time-date stamped

Up to two years of data stored in memory

Automatic schedule acceleration when rate of change alarm limit

exceeded (Default: 1 hour)

System performs periodic autocalibration to NIST traceable gas standard

Alarms

For each individual gas measured:

Two individually programmable caution and alarm settings for level

(ppm) as well as rate of change (ppm/day)

Freely programmable relay contact for gas alarm or service event

One relay contact for self-monitoring of power supply

External sensors

Current sensor for load-dependent gas development

Ambient temperature

Moisture in oil and oil temperature

Communications options

Standard physical layer interfaces include RS-232, RS-485, Ethernet

(10/100Base-TX), V.92 internal POTS modem

Optional physical layer interfaces include cellular modem, Ethernet

(100Base-FX), wireless radio

Three 4-20 mA inputs and one RS-232 port available to connect to

optional devices

Protocols supported: TCP/IP, DNP3, Modbus RTU and ASCII, OPC

Gas chromatography has long been the accepted standard for the measurement of dissolved gas levels in transformer oil. GAS-Guard 3 provides accurate and repeatable measurement of three critical fault gases, as well as other significant parameters. GAS-Guard 3 brings the DGA laboratory to your transformer with its rugged, closed-loop gas chromatograph, packaged in a compact design to be mounted on or near the subject transformer.

Key benefits include

• Field-based fully automated DGA requires no manual oil sampling or remote lab testing

• Accurate and timely DGA results improve ability to protect transformer against fault damage

• Data generated can be used to support condition-based maintenance programs

• Time/date-stamped test results allow correlation between real events and measured conditions

• Performs periodic auto-calibration to the National Institute of Standards and Technology’s (NIST) traceable gas standard, assuring accurate and reliable data

Graphical representation of GAS-Guard 3 connected to the transformer tank

Siemens Industry, Inc.7000 Siemens Road Wendell, NC 27591

For more information, please contact our Customer Support Center. Phone: 1-800-347-6659

usa.siemens.com

Order No: IC1000-E240-A144-X-4AUSPrinted in USA©2016 Siemens Industry, Inc.

Subject to changes and errors. The information given in this document only contains general descriptions and/or performance features which may not always specifically reflect those described, or which may undergo modification in the course of further development of the products. The requested performance features are binding only when they are expressly agreed upon in the concluded contract.