DGA Fault Triangles
DGA Fault Triangles for Power BI — End User Documentation
DGA Fault Triangles helps Power BI users visualize dissolved gas analysis results and classify transformer fault patterns using Duval Triangle methods. The visual supports Triangle 1, Triangle 4, and Triangle 5, with customizable segment colors, marker symbols, legends, and point connectors.
Product details
- Product
- DGA Fault Triangles
- Publisher
- ReadyViz.com
- Platform
- Microsoft Power BI custom visual
- Last reviewed
- 2 May 2026
When to use DGA Fault Triangles
- Visualizing transformer DGA sample results.
- Classifying known or suspected transformer faults.
- Comparing samples across assets, dates, or operating conditions.
- Showing a sample path over time with connector lines and arrowheads.
Do not use it as
- A replacement for lab quality checks or engineering review.
- A standalone transformer health index.
- A fault detection method when no abnormal gas condition has been established.
- The only decision source for maintenance, outage, or safety actions.
Quick start
- Install the visual. In Power BI Desktop or the Power BI service, open your report, go to the Visualizations pane, select the ellipsis, choose Get more visuals, select AppSource visuals, search for DGA Fault Triangles, and select Add.
- Add the visual to the report canvas. Select the DGA Fault Triangles icon in the Visualizations pane.
- Map your DGA fields. Add the required gas concentration fields for the selected triangle method. Use numeric concentration values and keep units consistent across gases.
- Select the triangle method. Open Format visual > Chart and choose Triangle 1, Triangle 4, or Triangle 5.
- Review the plotted points. Each sample is plotted inside a fault segment. Use labels, colors, and marker symbols to make segment categories easy to read.
- Optional: show trends. Enable the Connector card to draw lines between points. Use arrowheads when you want to indicate movement from earlier to later samples.
- Optional: add your license key. Open Format visual > About and paste your license token into License Key.
Data requirements and preparation
Each row should represent one DGA sample or one point to plot. Gas concentration values should be positive numeric values. DGA data is commonly entered in ppm, but all gases used by the selected method must use the same unit.
| Field | Purpose | Example |
|---|---|---|
| Asset or transformer identifier | Groups results by transformer or asset. | TX-102 |
| Sample date or sequence | Controls chronological analysis and helps connector lines represent trends. | 2026-04-15 |
| Gas concentration fields | Provide the numeric values used to calculate the triangle position. | CH₄, C₂H₂, C₂H₄, H₂, C₂H₆ |
| Sample label | Provides a readable point label or tooltip value. | Sample A-0415 |
| Triangle method | Typical purpose | Standard gas combination |
|---|---|---|
| Triangle 1 | Primary DGA fault classification. | Methane CH₄, acetylene C₂H₂, ethylene C₂H₄. |
| Triangle 4 | Additional classification for low-energy or low-temperature conditions. | Hydrogen H₂, methane CH₄, ethane C₂H₆. |
| Triangle 5 | Additional classification for medium- to high-energy thermal conditions. | Methane CH₄, ethylene C₂H₄, ethane C₂H₆. |
C₂H₂% = C₂H₂ / (CH₄ + C₂H₂ + C₂H₄) × 100
C₂H₄% = C₂H₄ / (CH₄ + C₂H₂ + C₂H₄) × 100
Interpretation workflow
- Validate the DGA sample: lab result, sampling date, transformer, and units.
- Check that interpretation is appropriate using internal thresholds, trends, alarms, or engineering review.
- Start with Triangle 1 for general DGA fault classification.
- Use Triangle 4 when Triangle 1 indicates a low-energy or low-temperature condition such as PD, T1, or T2.
- Use Triangle 5 when Triangle 1 indicates thermal faults such as T2 or T3.
- Review the segment assignment against sample history, load, temperature, transformer design, and other diagnostic methods.
- Document the triangle type, gas values, plotted segment, and follow-up action.
Format pane settings
About
Support, version, and licensing information. Paste the license key exactly as provided, then review Info, Plan Name, and Plan Expired when confirming licensing status.
Chart
Select Triangle 1, Triangle 4, or Triangle 5. Use Plot Projections for Unknown Segment to display projected points even when a point does not match known segment rules.
Legend
Turn the legend on or off and edit displayed labels such as PD, T1, T2, T3, D1, D2, DT, S, C, O to match company terminology or report language.
Segments
Set segment fill colors and marker symbol type, color, and size for PD, T1, T2, T3, D1, D2, DT, S, C, O, and Unknown. Use high-contrast markers for readability.
Connector
Show lines between points, choose color, thickness, style, optional background stroke, and arrowheads for chronological sample paths.
Recommended defaults for first-time users
Troubleshooting
| Issue | Likely cause | What to check |
|---|---|---|
| The visual is blank. | Required fields are missing or gas values are blank. | Confirm the selected triangle method has all required gas fields mapped and numeric values. |
| A point appears as Unknown. | The sample does not match a known segment rule or cannot form a valid triangle point. | Check gas values, units, blanks, zero totals, and Plot Projections for Unknown Segment. |
| Connector lines do not show the expected path. | Samples may not be sorted in the intended sequence. | Check sample date, sequence field, and filters. Use arrowheads when direction matters. |
| Legend text does not match company terminology. | Default segment labels are being used. | Open Format visual > Legend and edit the label text. |
| Markers are hard to see. | Marker color, segment fill color, or symbol size has low contrast. | Increase Symbol Size, change Symbol Color, or adjust segment fill colors. |
| License information looks incorrect. | The key may be missing, expired, mistyped, or not persisted. | Open About, re-enter the key, and include Version and Info values in support requests. |
Glossary
DGA: Dissolved gas analysis, a transformer oil test used to measure gases generated inside oil-filled equipment.
Duval Triangle: A triangular diagnostic method that plots relative gas percentages to classify transformer fault types.
PD: Partial discharge. T1/T2/T3: thermal fault temperature bands. D1/D2: low- and high-energy discharge. DT: mixed thermal and electrical fault pattern.
S, C, O: follow-up regions used in Triangle 4 and Triangle 5. Unknown: a point that the visual cannot assign to a known segment rule.