DGA diagnostics page - OPT100

OPT100 User Guide

Document code
M211858EN
Revision
AA
Language
English
Product
OPT100
Document type
User guide
CAUTION

This software utilizes publicly available and commonly used dissolved gas analysis (DGA) method for transformer fault diagnostics purposes, Duval Triangles (IEC 60599, Annex B).

Customer acknowledges and agrees that Vaisala shall not assume any risk or liability in connection with the use or application of the diagnostics data by the Customer or any other user of such data. The use and/or application of any such data shall be at the sole risk and liability of the Customer or the user.

DGA Diagnostics is an optional feature and requires a license.
Figure 1. Duval triangles on the DGA diagnostics page

DGA Diagnostics page shows the progression of selected data points from the past year overlaid on top of Duval triangles:

  • Triangle 1: Classic Duval triangle for DGA in oil-filled transformers using methane, ethylene, and acetylene
  • Triangle 3 for synthetic ester liquids: Duval triangle for DGA in synthetic ester filled transformers using methane, ethylene, and acetylene 1
  • Triangle 3 for natural ester liquids: Duval triangle for DGA in natural ester filled transformers using methane, ethylene, and acetylene 2
  • Triangle 4: Diagnosis of low-temperature faults in oil-filled transformers using hydrogen, methane, and ethane
  • Triangle 5: Diagnosis of low-temperature faults in oil-filled transformers using methane, ethylene, and ethane
Only Triangle 3 is visible in DGA monitors with ester liquid.

DGA monitor automatically selects the data points according to criteria described in section Criteria for data points in DGA diagnostics. The data points are listed in a table below the triangles. Clicking a table row highlights the data point in the overlay and displays the gas ratios as percentages.

1 Triangle 3 for synthetic ester liquids applies primarily to Midel 7131. It should apply to Cargill Environtemp 260/300 as well, but it is not verified.
2 Triangle 3 for natural ester liquids applies primarily to FR3. It should apply to other soy bean natural esters as well, but it is not verified.