DGA Monitor Product Selector
PAS DGA offers four distinct dissolved gas analysis solutions — from an OEM-grade hydrogen sensor probe to a full laboratory-grade multi-gas monitor. All built on proprietary palladium-nickel (Pd-Ni) alloy thin-film sensor technology. Use this guide to find the right monitor for your transformer application.
Find your monitor in three questions. Pick the application, add the system voltage, and say what you need the data for. The tool returns the model this page’s selection table points to first, plus the trade-off worth weighing. It states no figures of its own — open the model page for the specification.
Pick an application above and the tool returns the model this page’s selection table points to, with the trade-off to weigh. Not sure which application you have? Use the model links below, or send us the nameplate.
Key figures at a glance
- Multi-gas monitors measure on a cycle of 1 to 24 hours (default 4 hours) — up to 6 measurements per day with no operator involvement.
- Palladium-alloy hydrogen sensors hold ±15% of reading or ±5 ppm accuracy with no routine calibration.
- The laser photoacoustic (LPAS) detection cell has no consumables and its laser diode is rated for more than 50,000 hours of continuous operation.
Product Family Overview
| Model | Type | Gases | Detection | Best For |
|---|---|---|---|---|
| DGA-300 | OEM Sensor Probe | H₂ | 2 ppm | System integrators, custom monitoring platforms, OEM partners |
| DGA-500 | Standard Online Monitor | H₂ | 5 ppm | Cost-sensitive deployments, distribution transformers, fleet rollouts |
| DGA-200 | Advanced Online Monitor | H₂ + Multi-Gas (optional) | 5 ppm H₂ | Remote substations, SCADA integration, multi-gas capable |
| DGA-900 | Multi-Gas Online Monitor | 7 fault gases + moisture | Sub-ppm (LPAS) | Large power transformers, critical assets, full DGA diagnostics |
Quick Selection by Application
| Application | Voltage | Recommended | Why |
|---|---|---|---|
| Distribution Transformer | < 69 kV | DGA-500 | Cost-effective H₂ monitoring, zero maintenance, 10-year sensor life |
| Power Transformer | 69–230 kV | DGA-200 | H₂ + optional multi-gas upgrade path |
| Large Power Transformer | 230–500 kV | DGA-900 | Full 7-gas + moisture, laser PAS sub-ppm detection |
| Generator Step-Up | Any | DGA-900 or DGA-200 | Multi-gas for comprehensive fault coverage; H₂ for budget-conscious |
| HVDC Converter Transformer | ±500 kV+ | DGA-900 | Sub-ppm multi-gas with photoacoustic spectroscopy, full Duval Triangle diagnostics |
| Industrial / Arc Furnace | < 69 kV | DGA-500 | Rugged IP65 cast aluminum, vibration-resistant, -40 to +85°C |
| Offshore / Marine | Any | DGA-200 or DGA-900 | No cabling required, salt-fog resistant |
| OEM / System Integration | N/A | DGA-300 | Compact probe form factor, 4–20 mA + RS-485, <10 μA standby |
| Railway Traction | 25 kV | DGA-500 | Compact, vibration-resistant, <60s response time |
Detailed Feature Comparison
| Feature | DGA-300 | DGA-500 | DGA-200 | DGA-900 |
|---|---|---|---|---|
| Product Type | OEM Probe | Standard Monitor | Advanced Monitor | Multi-Gas Monitor |
| Gases Detected | H₂ | H₂ | H₂ + optional: CO, CH₄, C₂H₂, C₂H₄ | 7 gases + Moisture |
| Detection Limit | 2 ppm | 5 ppm | Not specified | Sub-ppm (LPAS) |
| Sensor Technology | Pd Alloy MOSFET | Pd Alloy Thin-Film | Pd Alloy Thin-Film | Multi-Channel LPAS |
| Response Time | < 10 min | < 30 min | Not specified | <120 s (full cycle) |
| Communication | 4–20 mA, RS-485 MODBUS | MODBUS, 4–20 mA | MODBUS RTU, 4–20 mA | MODBUS RTU |
| Enclosure Rating | IP67 (probe) | IP67 | IP66 | IP65 |
| Operating Temp | 0 ~ 60 ℃ | −40 ~ 105 ℃ | −40 ~ 105 ℃ | -40 to +70°C |
| Sensor Life | 10 Years | 10 Years | 10 Years | 10 Years |
| Key Advantage | 2 ppm limit of detection in an OEM probe | Standalone monitor mounted at the transformer valve | H₂ plus an optional multi-gas upgrade path | Lab-grade multi-gas spectroscopy in an online monitor |
Sensor Technology: Why Palladium Thin-Film?
All PAS DGA monitors use palladium (Pd) alloy thin-film sensors fabricated with MEMS processes. Unlike electrochemical sensors that degrade or gas chromatography that requires consumables, our solid-state technology delivers:
- Zero consumables — no carrier gas, no calibration gas, no columns
- 10-year expected sensor life — no electrolyte depletion, no mechanical wear
- Hydrogen-specific — Pd alloy selectively absorbs only H₂ molecules
- Instant-on — no warm-up period, <60 seconds to first reading
Learn more: Palladium Thin-Film Technology Deep-Dive | Hydrogen Sensor Product Family
Need Help Deciding?
Our application engineers will recommend the right DGA solution based on your transformer specifications, operating conditions, and budget. Typical response time: same business day.
Also Available
| Category | Products | Link |
|---|---|---|
| Hydrogen Sensors | Full Pd thin-film sensor portfolio — DGA-300, DGA-500, DGA-200 H₂ module | View Hydrogen Sensors |
| Accessories & Software | Mounting kits, communication modules, calibration tools, spare parts, PAS Dashboard software | View Accessories |
| All Products | Complete DGA product catalog with detailed specifications | View All Products |
Not Sure Which Monitor Fits Your Application?
Send us your transformer specifications and operating conditions. Our application engineers will recommend the optimal DGA solution — same business day response.
FAQ
Q: What gases does a DGA monitor detect?
A: The DGA-900 detects 7 fault gases plus moisture: hydrogen (H₂), carbon monoxide (CO), carbon dioxide (CO₂), methane (CH₄), ethane (C₂H₆), ethylene (C₂H₄) and acetylene (C₂H₂), plus moisture (H₂O). The DGA-200/300/500 hydrogen sensors detect H₂ down to 2 ppm.
Q: What communication protocols are supported?
A: MODBUS RTU (RS-485) digital output and 4–20 mA analog output, with programmable dry-contact relay alarms. The exact interface set differs by model — see the product page or datasheet for the interfaces supplied with each unit.