Return Sediver

Insulators’ ageing in North America – How about testing them?

Sediver has established in the USA an assembly factory for glass insulators in 2017 but also, and perhaps more interesting for some engineers, a laboratory capable of performing all the tests required by the world’s standards. Large test campaigns have already been conducted in this laboratory for numerous north American utilities from East Coast to West Coast.

Why testing?

The age of the transmission grid in the United States requires an increased focus on the condition of old insulators and many utilities have started testing some of their oldest lines in order to forecast and plan for refurbishment and capex expenditure.

How about testing?

  • Take insulators down for testing
  • Full strings with well referenced position in a given string
  • Decide a test plan for the evaluation
    • Standards have changed and are still changing
    • Tests should be performed as per latest knowledge and not necessarily only as per standards in place when those units were produced

What matters is expected resilience and expectations as per current quality of service

What tests can Sediver perform for you?

Une image contenant intérieur, table, bâtiment, pièce

Description générée automatiquement

Mechanical laboratory

  • M&E Tensile
  • Thermo-Mechanical Tensile
  • Residual Precondition Thermal Shock Tanks

Electrical HV laboratory

  1. AC and DC Type Tests
  2. 1.3MV Impulse Generator
  3. Steep Front Wave
  4. 250KV Power Frequency
  5. Wet & Dry Flashover
  6. Oil Puncture
  7. Corona/RIV Chamber

Example of case studies performed in Sediver laboratory


The US Grid has millions of old insulators mostly porcelain which often are close to their end of life

  1. Assessment of such insulators is an extremely valuable approach to reliability assessment and risk management
  2. Sediver West Memphis laboratory is performing such work on a monthly bases supplying US utilities with clear factual diagnostics
  3. Sediver West Memphis laboratory can carry out any type test as per IEC, CSA and ANSI

Extensive technical support in the north America

Sediver offers services in its West Memphis facility, which has capabilities to perform all the tests described in ANSI, IEC and CSA. Besides having access to the test equipment and results, utilities can draw upon Sediver’s unique expertise in the evaluation of the results, helping making sense out of the raw data collected from these test campaigns

Our team can help you:

  • Evaluate the performance of new designs
  • Select the optimum insulation solution
  • Determine the pollution levels on site to define the best options
  • Evaluate old insulator performance
  • Investigate options for refurbishment or upgrade of your lines
  • Train your team in all the stages of the insulation work

For more technical info

please contact Alexandre Matte

Technical Assistance Manager

Worldwide additional support

  • Sediver operates 5 laboratories worldwide (Shanghai China, Nusco Italy, West Memphis USA and the R&D facilities in France St Yorre and Bazet UHV laboratory)
  • All the factory laboratories benefit of full and constant support from R&D
  • Complex case studies were handled over the last years including the refurbishment and upgrade of a major DC line in the US

Want more info?

Read our technical paper about “Evaluation of Field Returned Insulators from U.S. Grid Through Laboratory“ presented during 2019 INMR.