Effective February 20, 2016

Standard Information
Standard Number:
UL 458
Standard Name:
Power Converters/Inverters and Power Converter/Inverter Systems for Land Vehicles and Marine Crafts
Standard Edition and Issue Date:
5th Edition Dated April 19, 2006
Date of Revision:
February 20, 2013
Date of Previous Revisions to Standard:
5th Edition Dated March 18, 2010
Effective Date of New/Revised Requirements

Effective Date (see Schedule below): February 20, 2016

Impact, Overview, Fees and Action Required

Impact Statement: A review of all Listing Reports is necessary to determine which products comply with new/revised requirements and which products will require re-evaluation. NOTE: Effective immediately, this revised standard will be exclusively used for evaluation of new products unless the Applicant requests in writing that current requirements be used along with their understanding that their listings will be withdrawn on Effective Date noted above, unless the product is found to comply with new/revised requirements.

Overview of Changes: UL 458 5th edition was revised to edit supplementary protectors in the output alternating circuits of recreational vehicle inverters for consistency and compliance with Article 551.43 of the National Electrical Code, NFPA 70. Specific details of new/revised requirements are found in table below.

Schedule: So that shipping of products with Listing Marks will not be interrupted, an approximate schedule has been established to ensure Listing Reports are found compliant by Effective Date:

  • June 1, 2015 = 7-8 Month Report Review – Intertek will review all Reports. Update if compliance is verified or issue Findings Letter/Quote for any re-evaluations needed
  • July 30, 2015 = 6 Month Quote Cut-off – Quotes returned for necessary re-evaluations
  • January 28, 2016 = 30 Day Warning – Client advised of all non-compliant Reports to be Suspended
  • February 20, 2016 = Effective Date – ATM Suspended for all non-compliant Reports

Fees: An initial review of Listing Report (s) will be covered by a direct billing project and will be invoiced at not more than $1000 per report.

Client Action Required:

Information - To assist our Engineer with review of your Listing Reports, please submit technical information in response to the new/revised paragraphs noted in the attached or explain why these new/revised requirements do not apply to your product (s).

Current Listings Not Active? – Please immediately identify any current Listing Reports or products that are no longer active and should be removed from our records. We will do this at no charge as long as Intertek is notified in writing prior to the review of your reports.

Description of New/Revised Technical Requirements
20InfoOverload-Protective Devices
20.2InfoOvercurrent-overtemperature protection

Additions to existing requirements are underlined and deletions are shown lined out below.

If secondary output load branch circuit overcurrent protection is provided, the overcurrent-protective devices shall be fuses or manually reset circuit breakers. The protective devices for alternating current output circuits of recreational vehicle inverters shall be suitable for branch circuit protection. See 6.8 – 6.9.

CUSTOMERS PLEASE NOTE: This Table and column "Verdict" can be used in determining how your current or future production is or will be in compliance with new/revised requirements.

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