Will the Test-Um Validator work for fibre cable?

Yes. Whilst the Test-Um Validator and Test-Um Validator-NT are for testing copper cabling only, JDSU (the company that took over Test-Um) have now released two new products based upon the Validator technology. The JDSU ValidatorPRO and JDSU ValidatorPRO-NT both have the ability to test fibre as well as copper cabling.