A revision of UL 1449 went into effect on February 9, 2007. This revision adds intermediate fault current tests for SPDs (surge protection device). Before the February 9 revision, only high current fault current testing was specified by UL 1449.

Testing

Now, when UL tests a SPD, they will apply a fault current of 100A, 500A and 1000A for permanently connected SPDs and 50A and 150A for plug-in and cord connected SPDs. These currents are applied using line to line voltage in the line to neutral mode. During this testing, the SPD must fail in a safe manner to be UL 1449 listed. In the event that the SPD does not conduct the defined current, UL can increase the voltage or request a sample with a lower voltage rating.  

Product Labeling

As of February 9, 2007, any SPD manufactured must have passed all of the abnormal power tests to be labeled with the UL logo. However, those SPDs with a manufacturing date code prior to that date may still be sold with the logo.  

UL 3^rd Edition

A new revision of UL 1449 requires compliance by 2009. At that time, the test levels for VPRs (voltage protection ratings) will increase. Currently, the 2^nd Edition measures the VPR with a surge of 6,000V at 500A. The 3^rd Edition will increase the amperage six times to 3000A at 6,000V. Because of the change, VPRs for products tested under 2^nd edition may need to increase.

A new kA rating, I_n, for SPDs will be added to 1449 with the 3^rd Edition. The kA rating, up to 20kA, will be identified by the SPD manufacturer and tested by UL. UL will subject the SPD to 15 surges at the manufacture’s defined I_n level, minimum of 6kV. The VPR is tested again after the SPD successfully passes the 15 surge I_n test. If the associated VPR is consistent with the SPDs original test, the rating can be applied to the SPD label.