Precision Dissolved Gas Analysis for the World's Transformers
From single-gas hydrogen sensors to comprehensive 9-gas Laser Photoacoustic Spectroscopy (LPAS) — PAS DGA offers the industry's most complete range of online transformer monitoring solutions. Zero consumables, lab-grade accuracy, direct oil immersion.
Two Product Families. One Technology Platform.
From hydrogen-only sensors for fleet-wide deployment to comprehensive 9-gas LPAS systems for critical assets — all built on proprietary palladium alloy thin-film technology. Engineered in Shenzhen, deployed worldwide.
Hydrogen Sensors
Pd Alloy Thin-Film — DGA-200 / 300 / 500 Series
The industry's most complete range of solid-state hydrogen sensors. From the 2 ppm OEM probe (DGA-300) to the field-proven workhorse (DGA-500) to the multi-gas monitor (DGA-200). All share the same zero-maintenance Pd alloy thin-film core and a 10-year expected service life.
- 2 ppm Detection
- 2–5,000 ppm Range
- MODBUS RTU (RS-485) + 4–20 mA
- IP67 Rated
- 10-Year Sensor Life
- Zero Consumables
DGA-900
Laser Photoacoustic Spectroscopy — Full 9-Gas + Moisture
Laboratory-grade comprehensive DGA in real time. 9 fault gases plus moisture via Laser Photoacoustic Spectroscopy (LPAS). 0.1 ppm C2H2 detection. Deployed at China's 1000 kV UHV substations and ±800 kV HVDC converter stations. Three configuration modes: Module Only, Standard System, Premium System.
- 9 Gases + Moisture
- 0.1 ppm C2H2
- IEC 61850 + MODBUS RTU
- Duval / Rogers / Doernenburg
- 72-Hour Early Warning
- Comprehensive Warranty
PAS DGA Technology — Two Core Innovations
Every PAS DGA monitor is powered by two proprietary technologies developed and manufactured in-house. Together they deliver lab-grade accuracy with zero consumables and 10-year sensor life.
Photoacoustic Spectroscopy (PAS)
Photoacoustic spectroscopy detects dissolved gases by their characteristic infrared absorption spectra. A modulated light source excites gas molecules, generating acoustic waves proportional to concentration — no carrier gas, no columns, no flame ionization detector. Our Laser PAS (LPAS) variant in the DGA-900 narrows the optical line width far below that of broadband IR sources, which suppresses cross-interference between gas species.
Used in: DGA-200 (IR-PAS module) and DGA-900 (LPAS, 9 gases)
Palladium Alloy Thin-Film H2 Sensing
Our palladium–nickel (Pd-Ni) alloy thin-film sensor detects dissolved hydrogen by direct oil immersion — no membrane, no oil-gas separation, no consumables and no heater, with a 10-year expected life. The Pd lattice absorbs H2 selectively; the manufacturer reports no interference from CO or CH compounds. Two sensor structures are used across the range: a palladium alloy thin-film resistor (DGA-500, 5–5,000 ppm) and a palladium alloy MOSFET (DGA-300, 2–2,000 ppm).
Used in: DGA-200, DGA-300, DGA-500 — all hydrogen sensor models
DGA Knowledge Base
DGA Fundamentals
The 7 key fault gases — sources, generation mechanisms, and what each gas reveals about transformer condition.
Start Learning →Diagnostic Methods
Duval Triangle, Rogers Ratio, IEC 60599, Key Gas Method — complete reference with interpretation examples.
Read →Fault Types & Gas Signatures
Thermal faults, partial discharge, arcing — complete diagnostic reference with characteristic gas ratio patterns.
Read →Duval Triangle Guide
Step-by-step guide to the most widely used DGA interpretation method — Duval Triangles 1 through 5 explained.
Read →Why International Buyers Choose PAS DGA
ISO 9001 certified manufacturing. Direct from manufacturer.
Industries & Applications
From 1,000 kV UHV substations to remote wind farms — PAS DGA serves every power transformer application. Hydrogen sensors for fleet-wide deployment. DGA-900 LPAS for the most critical assets.
Power Utilities
Transmission & distribution. 110 kV to 1,000 kV UHV. Fleet-wide condition-based maintenance.
Learn more →Heavy Industry
Steel, chemicals, mining. Critical process transformers where downtime costs millions per day.
Learn more →Renewable Energy
Wind, solar, BESS. Remote assets, variable loads. Condition monitoring built for unmanned sites.
Learn more →HVDC & UHV
Converter transformers. Autotransformers. DGA-900 LPAS for the most demanding applications on the planet.
Learn more →ISO 9001 Certified · IEC 60599 & IEEE C57.104 Interpretation Methods · Global Shipping
Request Pricing & Availability →Application Scenarios
How PAS DGA monitoring is specified across demanding transformer applications.
Arc furnace and rectifier transformers run cyclic overload duty. Hydrogen trend — not a single reading — is the earliest indicator of incipient thermal faults, giving maintenance planners time to schedule work before an unplanned outage.
Heavy Industry
Arc Furnace · Rectifier Transformers · Cyclic Load
Step-up transformers at offshore and remote renewable sites are expensive to visit. Valve-mount hydrogen sensors monitor them continuously and report over MODBUS RTU (RS-485) or 4–20 mA, so site attendance follows condition data rather than a fixed schedule.
Renewable Energy
Offshore & Remote Sites · Step-Up Transformers
Safety-related transformers require a documented, repeatable measurement record. Pd alloy thin-film sensors are field-verifiable against ASTM D3612 offline DGA, with recalibration indicated only when deviation exceeds ±15% of reading.
Safety-Related Applications
Nuclear · Auxiliary Transformers