The standard for Industrial Control Equipment UL 508 has been harmonized with the relevant product standards of the IEC standard for Low-Voltage Switchgear and Controlgear IEC 60947.
This harmonization work was undertaken with the intent of creating standards that, while being based upon and adopting IEC requirements, would incorporate sufficient national differences to ease the transition from UL 508 to UL 60947-4-1A. This goal has largely been accomplished in all cases. While the UL 508 and UL 60947 series standards do not look the same, when taking into account the national differences included in the harmonized standards, they are essentially technically identical.
The three transition phases are:
Before January 26, 2012:
Product submittals will be evaluated to UL 60947-4-1A unless customers specifically request in writing that they be evaluated using UL 508.
January 26, 2012-January 26, 2017:
New product submittals will be evaluated to UL 60947-4-1A only; however revisions to existing products may still be evaluated using UL 508 if customers specifically request this in writing.
Effective January 27, 2017:
All UL certified products must meet UL 60947-4-1A only.
UL certification to UL 508 will be withdrawn.
The requirements in UL 508 and UL 60947-4-1A are at this time technically identical. Most products complying with UL 508 also comply with UL 60947-4-1A. Because the documents are technically identical at the present time it is not anticipated there will be a need for a technical review or Industry File Review of products evaluated to the affected UL 508 CCNs for compliance with UL 60947-4-1A.
Please be aware that our EBC31 controls and motor controllers have already been upgraded to the new UL60947 standard and other product will be upgraded prior to January 1, 2017.