Gas monitoring in transformer less-component oils: Selection points for lightweight DGA solutions
Date: May 19, 2026 14:12:02
- Less Component DefinitionOnline monitoring of gases in low-component oil means a lightweight DGA solution that detects only 3-5 critical fault gases (instead of the full complement of 7+), finding a balance between cost and economy.
- Typical Configuration: the most common less-component combinations are H₂, CH₄, C₂H₄, C₂H₂ plus CO, which covers the basic judgment needs of discharge faults and thermal faults, and is a cost-effective compromise between
- Applicable Scenarios: 110kV and below urban substations, industrial customer-owned transformers, and all types of distribution transformers with limited budgets that still require online monitoring.
- Key to Selection: Reducing the number of components is not simply a matter of cutting out a few gases - which gases are worth retaining depends on the operational characteristics of the transformer and the main types of risks
1. Positioning of the sub-component program
In the field of transformer oil chromatography online monitoring, full-component solutions detect more than seven gases, covering all fault types, but with high equipment investment and O&M costs; single-hydrogen solutions detect only hydrogen, with the lowest investment, but are unable to differentiate between fault types. Less-component solutions fall somewhere in between - retaining the minimum number of gases needed to diagnose the core fault, and providing acceptable diagnostic capability for a moderate investment.
Rather than pursuing an all-encompassing approach, the less-component program selects the critical gases corresponding to the most likely failure types of the target transformer to be monitored. This demand-driven selection strategy is the core logic of the less-component program.
2. Common less-component configurations
| Configuration options | Detecting gases | Types of faults that can be determined | Scenario |
|---|---|---|---|
| Hydrogen + Acetylene Dual Gas | H₂, C₂H₂ | Discharge faults (arcing, localized discharges) | Older transformers where discharge is the main risk |
| Three-gas basic | H₂, CH₄, C₂H₂ | Discharge fault + low temperature overheating | General distribution transformers |
| Four Gas Enhanced | H₂, CH₄, C₂H₄, C₂H₂ | Discharge + low temperature overheat + high temperature overheat | 110kV City Substation Main Transformer |
| Five-gas carbon-oxygen type | H₂, CO, CH₄, C₂H₄, C₂H₂ | Discharge + overheating + solid insulation aging | Transformers with long operating life |
3. Selection considerations
3.1 Transformer risk characteristics determine the gas mix
The operating conditions and history of different transformers determine the main types of risk. Transformers operating at high loads for long periods of time are predominantly at risk of overheating and should ensure that they contain ethylene; transformers with a long operating life and a history of discharges should ensure that they contain acetylene; and transformers with insulation ageing concerns should not be without carbon monoxide.
3.2 Diagnostic complementarity between gases
Hydrogen alone detects anomalies but does not know what type of anomaly; the addition of methane and ethylene determines the temperature range; the addition of acetylene determines if there is a discharge; and the addition of carbon monoxide determines if the insulation is deteriorating. Selection should ensure that the combination of gases chosen covers the most critical failure modes of the target transformer.
3.3 Space for future expansion
Some of the less-component systems have expansion capability built into the hardware level - upgrading to more gas configurations is possible by adding columns or detection channels. If you have a limited initial budget but plan to upgrade in the future, choosing a system with a modular design provides more flexibility.
4. Frequently Asked Questions FAQ
4.1 Q: Will a less-component scheme miss important fault signals?
A: This possibility exists. Each undetected gas corresponds to a blind spot in the determination of certain fault types. It is difficult to determine high temperature overheating without ethylene, and solid insulation deterioration cannot be seen without carbon monoxide. The central task in selection is to determine which blind zones are acceptable and which are not.
4.2 Q: Can the lesser components meet the utility's grid access requirements?
A: Different power companies have different technical requirements. Some provincial power grid companies have clear requirements on the minimum detection gas type for main transformer oil chromatography online monitoring. Before purchasing, you should confirm the technical standards of the local power grid company and the requirements for testing into the network.
4.3 Q. What is the price difference between lesser and full components?
A: The type of gas to be detected is an important factor in the cost of the system. Investment in equipment with fewer components is usually more economical. However, this should be assessed in a holistic manner - if a critical fault is missed due to the omission of a few gases, this saving is far from enough to cover the loss of a single fault.
4.4 Q: Can I upgrade from lesser to full components at a later stage?
A: Depends on the hardware architecture of the system. Modular design products can be upgraded by adding columns or detectors; integrated design products may need to replace the core analyzer unit or change the whole machine. The upgrade path and cost should be clarified with the supplier when selecting the model.
4.5 Q: Is the less-component scheme suitable for transformers above 110 kV?
A: Generally speaking, it is recommended to prioritize the configuration of full-component solutions for main transformers of 110kV and above voltage levels. However, if the budget is really limited, the enhanced less-component configuration of five-gas carbon-oxygen-containing can be used as a transitional program to meet the basic fault warning needs.
5. Summary
5.1 Fewer components is a demand-driven lightweighting option that centers on clarifying which gases correspond to the key risks of the target transformer.
5.2 Critical main transformers are not recommended to be selected with fewer components in order to save; the cost of diagnostic blindness may far exceed the savings invested.
5.3 Choosing a system with a modular design leaves room for future upgrades.
Disclaimer: The content of this article is for technical exchanges and reference only, and does not constitute any form of procurement commitment or contract offer. Product technical parameters, configuration programs and prices are subject to the actual signed contracts and technical agreements. The technical data and cases involved in this article are from public information and engineering practice, if updated without notice.
Need a gas monitoring solution for transformer less-component oil? Welcome to contact Inotera to customize the configuration according to your actual needs. Service hotline: 13959168359 (micro letter with number).
