UL certification in accordance with UL 1446 for your electrical insulation systems

Proving the product safety of your own equipment is becoming increasingly important in our globalized world. With certain standards and certifications, you obtain approval for your products, stand out against your competitors and establish yourself on the (international) market. Consumers in particular rely on certification marks and international standards for product quality and safety.

One of the most important and also globally recognized certifications for electrical insulation systems is the UL certificate according to UL 1446. With this seal, you prove to meet the general requirements with respect to the electrical safety of your products.

At SynLab^®, we offer comprehensive project services, help you test the materials you use and map test procedures to Standard UL 1446 under the UL Third Party Test Data Program.

UL Underwriters Laboratories is an independent organization that tests and certifies products with regard to their electrical safety. For the American and Canadian market, UL approvals and certifications are a prerequisite for a product's market approval. Founded in the USA in 1894, UL has evolved into a worldwide organization - accordingly, UL-certified products are recognized in the areas of fire protection and electrical safety as well as hazardous substances, water quality and food safety.

UL 1446 standard offers a guideline for the creation and expansion of electrical insulation systems in the low-voltage range and, in addition to administrative specifications, also provides descriptions of the tests to be carried out.

As part of the UL Third Party Data Test Program, we carry out projects in accordance with UL 1446 at SynFlex. In addition to the adaption, creation and extension of electrical insulation systems, we also offer you other comprehensive services in our test laboratory.

We take over the entire handling of your project, act as an interface between you and UL and ensure that your certification runs smoothly.

Once you need an electrical insulation system for your product, you have several options for selecting and using a system.

We have developed our own UL electrical insulation systems for different temperature classes in which you can use a wide range of our product program: insulating materials SynTherm^®, SynTape^® adhesive tapes, various potting compounds and our wires.

Did you know that you can find both our electrical insulation systems and other systems for adoption in UL's database? If one of these existing systems meets your requirements, you only pay a kind of license or user fee and may use it from then on.

If you cannot find a suitable electrical insulation system or want to make changes to an existing one, contact our experts and together we will work out a solution for your product. Whether you want to add more materials to a system or bring in a material alternative, we will take care of the communication with Underwriters Laboratories (UL), carry out the appropriate tests and ensure that your modified system is approved as quickly as possible.

We also carry out the development and testing of a completely new electrical insulation system and its approval in our laboratory. Typically, a complete ageing test (FTA) is carried out first, followed by a sealed tube test (CCT). Approval of the new system (including all tests to be carried out) usually takes at least one year.

The FTA test is a life test. We use it both when creating a new electrical insulation system and for existing systems to which further insulation materials are added.

To carry out the test, GPM models (General Purpose Model), so-called motorettes, are built up with the materials of the system. Typically, the motorettes are tested at three or four different temperatures in several cycles, using 10 GPM's per temperature.

Test cycle: At the highest temperature, the GPMs are aged for three days (seven days at the medium temperature and 28 days at the lowest temperature) in the heating cabinet. This is followed by a vibration test at 60 Hz for one hour, a cold shock test at -20 °C, and a humidity test at 92 to 100 per cent relative humidity at room temperature for 48 hours. At the end of each cycle, we perform the End of Life Test to check the electrical stability of the insulation system. The cycles continue until all ten GPMs fail.

At the end of the test, the system is assigned to its thermal class. Classification is made according to the determined and calculated average failure time.

As an alternative to FTA, you can add a non-insulating material (NIM) by means of compatibility testing with the CCT (Chemical Compatibility Test). Insulating components (EIM), however, can only be replaced or added by means of this test to a very limited extent. Benefits are significant cost and time savings.

The test is set up by creating 10 Twisted Pairs each with the materials of the original system (Reference Tube) and 10 Twisted Pairs with the materials that are to be newly included in the system (Substitute Tube). These gas-tight sealed glass flasks (Sealed Tubes) are then conditioned for 14 days at 25 degrees Celsius above system temperature. Finally, an electrical test of the enamelled wires (twisted pairs) is carried out to evaluate the thermo-chemical degradation of the enamelled wire insulation.

The test is considered passed if the twisted pairs from the substitute tube reach at least 50 percent of the reference tube.

You can use your adapted system immediately after successful testing and registration by UL.

IEC 60335-1, Appendix C describes the test method:

The Short-Term Thermal Aging (STTA) Test Program allows accelerated certification of electric motors in low-voltage applications (≤ 1000 Volt). The test program and certification of electrical insulation system meets the requirements of UL/IEC 60335-1, Appendix C for specified temperature classes (B, F, H etc.) for use in accordance with UL Standard 1004-X series (electrical rotating machines).

Brief description:

• E.g. desired thermal class B (130°C)
  (short-term test at temperatures up to 40 °C above thermal rating (e.g. 170 °C)
• 8 systems (test construction with 6 systems)
  2 systems used for screening (pre-test)
• Compact design (NEMA 56 frame or smaller)
• Motors with high resistance