Just wanted to thank you for your explanation. In this case, the
transformers are built in to the instrument, behind a panel that
requires a 'tool' (key locked) to gain entry. I did have some
confusion about this, because as you indicated, IEC 1010 doesn't
specify a specific transformer standard to follow.
I guess that we now have (2) choices -
1. Purchase and install transformers that have IEC 742 certification.
- or -
2. Purchase copies of both IEC 742 and IEC 950 and evaluate
whether the IEC 950 certified transformers meet the requirements
of IEC 742 for our equipment. This *may* involve additional testing
and would most certainly be more time consuming. Potentially it could
be less costly in the long run, as domestic manufacturers of general
purpose transformers seem to only be offering products with IEC 950
compliance. To get a transformer with IEC 742 compliance, I'd have
to switch from using Signal Transformer to Legrand or some other
European company.
-----------------------------------------
John Bielot
Canberra Industries
Applied Systems Division
e-mail: [email protected]
-----------------------------------------
>
>On 04-Feb-97 you wrote
>
>
>Hello from San Diego:
>
>
>IEC 742 (aka EN 60742) applies to transformers in general and
>stand-alone transformers in particular.
>
>IEC 742 contains some additional requirements for stand-alone
>transformers compared to those in IEC 950 (aka EN 60950).
>
>Unfortunately, IEC 1010 (aka EN 61010) does not contain specific
>transformer requirements, so IEC 742 can be invoked if the test
>house so chooses.
>
>If your transformer is built-in, then I believe a transformer
>complying with IEC 950 also complies with IEC 742.
>
>It may be that the test house is simply saying that an IEC 950
>certified transformer, by definition (not by test), does not
>comply with IEC 742. In other words, they cannot accept, carte
>blanche, the IEC 950 certification as being applicable to
>IEC 1010, whereas they could accept IEC 742 certification.
>
>This may mean that the test house will need to conduct tests to
>demonstrate compliance with IEC 1010.
>
>
>Best regards,
>Rich
>
>
>
>-------------------------------------------------------------
>Richard Nute Quality Department
>Hewlett-Packard Company Product Regulations Group
>San Diego Division (SDD) Tel : 619 655 3329
>16399 West Bernardo Drive FAX : 619 655 4979
>San Diego, California 92127 e-mail: [email protected]
>-------------------------------------------------------------
