Effective September 30, 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:
6th Edition Dated September 2, 2015
Date of Previous Revisions to Standard:
5th Edition Dated February 20, 2013
Effective Date of New/Revised Requirements

Effective Date (See Schedule below): September 30, 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requests in writing that current requirements be used along with their understanding that their listings will be withdrawn on Effective Date noted above, unless the product is found to comply with new/revised requirements.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: (specific details of new/revised requirements are found in table below);

  • Revisions to branch rated breakers in output circuit of inverter.
  • Revision of SA26.2 to replace of the Carbon Arc testing with Xenon Arc testing for UV exposure.

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:

  • January 29, 2016= 8 Month Report Review – Intertek will review all Reports. Update if compliance is verified or issue Findings Letter/Quote for any re-evaluations needed
  • March 30, 2016= 6 Month Quote Cut-off – Quotes returned for necessary re-evaluations
  • August 30, 2016= 30 Day Warning – Client advised of all non-compliant Reports to be Suspended
  • September 30, 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 – Please immediately identify any current Listing Reports or products that are no longer active and should be removed from our records.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
48InfoAbnormal Operation Test
48.2InfoOutput short-circuit
48.2.3 New clause added;

The external output connections of an inverter are to be short-circuited and the unit is to be connected to a source of supply adjusted to the inverter rated nominal input dc voltage. The source of supply may be protected by a time-delay overcurrent-protective device rated no less than 150% of the rated inverter input current at full rated load. During the test, the enclosure is to be connected directly to earth ground. A protective device such as an accessible fuse or circuit breaker provided as part of the unit is to remain in the circuit, and the largest fuse the fuse holder will accept is to be installed. When an inverter circuit employs a microprocessor to shut down a unit due to an overload, that portion of the software shall be disabled for this test.

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


Three test panels, see 52.2, are to be exposed to ultraviolet rays and water spray for 720 h. The test cycle is to consist of exposure to ultraviolet rays for 102 min followed by exposure to ultraviolet rays and a fine spray of water for 18 min using Type D apparatus, as described in Practice for Operating Light- and Water-Exposure Apparatus (Carbon Arc Type) for Exposure of Nonmetallic Materials, ASTM G23-1969.

Three test panels, see 53.2, are to be exposed to ultraviolet rays and water spray by Xenon-arc in accordance with the Standard Practice for Exposing Nonmetallic Materials in Accelerated Test Devices That Use Laboratory Light Sources, ASTM

G151, and the Standard Practice for Operating Xenon Arc Light Apparatus for Exposure of Non-Metallic Materials, ASTM G155. The spectral power distribution of the xenon lamp shall conform to the requirement in Table 1 in ASTM G155 for a xenon lamp with daylight filters. A programmed cycle of 120 min consisting of a 102-min light exposure and an 18-min exposure to water spray with light shall be used. The apparatus shall operate with a spectral irradiance of 0.35 W/m2 at 340 nm and a black-panel temperature of 63 ±3°C (145 ±5.4°F).

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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