• Resolved

ISO7742: About UL certification

Part Number: ISO7742

Hello support team,

I have some questions regarding UL certification of ISO7742DW.
I confirmed the status of ISO 7742 by UL certification search.
Just to be sure, I'd like to confirm the following contents.

A question
1. Is the UL certification condition correct as follows?
- UL file No: E181974
- Product category: FPPT 2
- Withstanding isolation voltage: 5700 Vac

2. The withstanding isolation voltage is specified as 5000 Vrms in the data sheet, why?
Isn't it 5700 Vrms?

3. cUL certification (FPPT8) does not seem to be certified. Is it correct?

Best regards,
M. Tachibana

  • Hi Tachibana-san,

    My responses to your questions are below:

    1. Yes, the information you listed is correct.

    2. We've certified ISO7742DW at 5.7 KVrms per UL 1577 but we're only guaranteeing 5 kVrms in the data sheet. If you need 5.7 kVrms for your application, then I suggest you consider ISO7842DW for your application.

    3. That's correct, we don't have cUL certification but if you need Canadian certification then please note that this device is CSA certified already.

    Saleem Marwat

    Systems Engineer

    Isolation Products, Texas Instruments

  • In reply to Saleem Marwat:

    Hello Marwat-san,

    Thank you for your prompt reply.
    Please let me ask another question.

    Why does ISO 7742 DW guarantee only 5 kVrms in the datasheet in spite of certification at 5.7 KVrms per UL 1577?
    Is there any reason why only 5 kVrms can not be guaranteed?

    Best regards,
    M. Tachibana
  • In reply to Masanori Tachibana:

    Hi Tachibana-san,

    Even though ISO7742DW is capable of supporting 5.7 kVrms, this device is intended for the market segment that needs 5 kVrms isolation. If 5.7 kVrms is needed, then ISO7842DW is a more appropriate choice.

    Saleem Marwat

    Systems Engineer

    Isolation Products, Texas Instruments

  • In reply to Saleem Marwat:

    Hello Marwat-san,

    Thank you for your information.
    I understood.

    Best regards,
    M. Tachibana