What are the main changes in the UL 1449 2007 revision?
A. In 1998, the UL 1449 2nd edition standard became effective with special provisions to address the “slow burn” or “thermal runaway” failure mode of surge protection devices, responsible for catastrophic events which could compromise the safety of electrical installations. In its 2007 revision, the UL 1449 standard extends the limit of the abnormal overvoltage short circuit current tests from 5 Amps to 1000 Amps with test duration of up to seven hours.
