Portable chromatograph for detecting dissolved gas in insulation oil of oil flushing appliances
Scope of application:
Power supply bureaus, power plants, oil flushing electrical appliances (including transformers, reactors, current transformers, voltage transformers, charging bushings, gas relays), etc
Introduction:
During long-term operation of oil flushing appliances, due to the gradual aging and deterioration of oil and solid insulation materials, a small amount of gas (mainly including 7 types such as H2, methane CH4, ethane C2H6, ethylene C2H4, acetylene C2H2, carbon monoxide CO, carbon dioxide CO2, etc.) will be decomposed. When there is a malfunction inside the oil flushing device, the gas production of these gases will rapidly increase. When the temperature at the fault point is low, the proportion of methane is high. When the temperature rises, the components of ethylene and hydrogen will increase sharply, and the proportion will increase. When severely overheated, acetylene gas can also be produced. When solid insulation experiences overheating faults, in addition to producing low molecular weight hydrocarbon gases, a significant amount of CO is also produced, C02。 As the temperature increases, the CO/CO2 ratio gradually increases, and the nature and degree of the fault can be determined by the content of various gas components in the oil. So during the operation of oil flushing appliances, regularly measuring the gas composition and content in the oil can timely detect latent faults inside the transformer. To ensure the safe and effective operation of the power grid is an effective means, and it is also a necessary means for oil charging equipment manufacturers to conduct factory inspections of their equipment.

Execution standards:
GB/T17623-1998 "Determination of dissolved gas components in insulating oil by gas chromatography"
GB/T7252-2001 "Guidelines for Analysis and Determination of Dissolved Gases in Transformer Oil"
DL/T 722-2000 "Guidelines for Analysis and Determination of Dissolved Gases in Transformer Oil"

Portable gas chromatograph (power system)Instrument features:
Equipped with a 7-inch large screen, the display content is rich and intuitive, and can directly display spectra and results.
● Equipped with 6 temperature controls, each set from room temperature to 450 ℃, increment: 1 ℃, accuracy: ± 0.1 ℃
Equipped with a 16 stage programmed temperature rise, it meets the requirements for complex sample analysis.
● Lift rate: 0.1-39 ℃/min (ordinary type); 0.1-80 ℃/min (high-speed type)
8 external control events can achieve instrument automation operation, and online analysis can be achieved through pipeline laying.
Multiple injection methods to choose from: column head injection, split/non split injection, valve injection, headspace injection.
Double column parallel connection, three detectors (FIDI, TCD, methane converter FIDII) process,
Complete the full analysis of 7 components of dissolved gases in insulating oil (H2, CH4, C2H6, C2H4, C2H2, CO, CO2) in one injection.
Choose between mechanical valve control or electronic proportional valve control (electronic proportional valve is 16 way control)
The gas pressure and flow rate are measured by precision sensors, and the measured values are displayed on the screen.
Two working modes of electronic proportional valve: 1. Constant current mode, 2. Constant pressure mode
5 types of gas media for electronic proportional valves; Nitrogen, hydrogen, air, helium, argon

Portable gas chromatograph (power system)Instrument parameters:
Pressure: 0-0.6Mpa; Flow rate 0-100 sccm or 0-500 sccm (air)
■ Control accuracy of electronic proportional valve:
Pressure: 0.01Kpa;
Flow rate: 0.01 sccm
Pressure sensor:
Accuracy:<± 2% of full scale
Reproducibility:< ±0.05 KPa
Temperature coefficient:< ±0.01 KPa/°C
Range: 0-0.3MPa or 0-0.6MPa;
■ Flow sensor:
Accuracy:<± 5% of full scale
Reproducibility:<± 0.5% (full scale)
Range: 0-500sccm
Hydrogen flame ionization detector (FID)
Detection limit: Mt ≤ 3 × 10-12g/s (n-hexadecane-isooctane solution);
Baseline noise: ≤ 5×10-14A
Baseline drift: ≤ 1×10-13A/30min
Linear range: ≥ one hundred and six
Thermal conductivity detector (TCD)
Sensitivity: S ≥ 3500mV • ml/mg (n-hexadecane isooctane solution) (amplification 1, 2, 4, 8 times optional)
Baseline noise: ≤ 10μV
Baseline drift: ≤ 30μv/30min
Linear range: ≥ one hundred and four
■Quantitative repeatability RSD ≤ 3%
Qualitative repeatability RSD ≤ 1%
■ Maximum detection concentration:

　　　
Configuration List: