Product Compliance Safety Testing - LTG Services, Inc. can help you get certified by UL,CUL,CSA,CE,FCC,and VCCI
Thought about certification? UL,CUL,CSA,CE,FCC,and VCCI?
Speeding your products to the global marketplace - http://www.LTGServices.com

Return to the Home Page To bottom of page About our company See our services How we do business with you Certification Agencies See our Compliance Corner Contact us here for more information

Compliance Questions


Welcome to Compliance Questions. At LTG Services we get many questions from our clients regarding product compliance. We would like to post your questions and our responses regarding product compliance on this page.

Please E-mail questions, comments and suggestions to webmaster@ltgservices.com

IP Hosedown Test

I have a question regarding the Hosedown test in the IP standard. I am looking for equipment to perform this test. Is there a company that supplies this type of equipment and what equipment models would be required to run this test?

The only place that I was able to find follows:

PTL Dr. Grabenhorst Gmbh Industrielstrasse 15 D-8652 Stadtsteinach Germany

49 92 25 9 86 0
Fax: 49 92 25 9 86 40

Additionally, we work with a local company that designs most of our test fixtures and custom test equipment. They probably will not have IEC 529 on hand and will request a copy or the specifications within.

RPI Inc 4139 Rickenbacker Drive Atlanta, GA 30342-3076

404-256-5944
Fax: 404-256-0609

Class 2 Power Supplies

Where can I find the requirements for classifying a power supply as "Class 2"? What agency/organization set this?

The original Class 2 requirements can be found in Article 725 of the National Electric Code (NEC, NFPA-70) and Section 16 of the Canidian Electric Code (CE Code, C22.1).

The US and Canadian standards for evaluating power supplies are UL 1310 (Class 2 Power Units) and CAN/CSA-C22.2 No. 223 (Power Supplies with Extra-Low-Voltage Class 2 Outputs), respectively.

The agencies are the National Fire Protection Association and the Canadian Standards Association.

Industrial Computers and UL 1998

How difficult is it to get a UL and CE mark on a small industrial computer?

What other certification should it get?

What is UL 1998 (see attached), and how difficult would the testing procedure be for this mark? (See attached.)

According to Flynn, who is responsible for developing investigation protocols for applying UL 1998, interest has come from U.S. organizations developing medical device regulations, OSHA, and the U.S. Voluntary Safety System. In Europe, interest has been expressed by those developing gas/oil, machinery, and medical device directives, she says. The updated UL 1998 version addresses risks that may result from faults caused by software errors, including the following: design errors, such as incorrect software algorithms or interfaces; coding errors, including syntax, incorrect signs, and endless loops; timing errors that can cause premature or late program execution; induced errors caused by hardware failure; latent, user, input/output, range and other errors that are only detectable when a given value or set of conditions occurs; and failure of the system to perform any function at all.

Flynn is hopeful UL's voting process will be completed by fall, and official American National Standards Institute (ANSI) approval is received by this December. Software suppliers conforming to UL 1998 receive a "Programmable Systems Certificate" specifying that their product meets the standard's requirements.

Research Triangle Park, N.C. -- Underwriters Laboratories (UL) this month plans to begin the voting process on a significantly revised version of a UL standard created to prevent programmable logic controller (PLC) software failures that could cause fire, electric shock, or personal injuries. Aimed primarily at PLC manufacturers and PLC software suppliers, the proposed Second Edition of the Standard for Safety-Related Software, UL 1998, addresses potential risks unique to equipment controlled by software. UL 1998 initially was aimed primarily at residential control systems, such as gas- and oil-fired appliances, temperature controls, and fire-alarm and suppression systems, says Robert A. Williams, UL corporate manager, standards and research. The updated edition has broader applications, addressing risks that may occur as a result of faults caused by errors in non-networked embedded microprocessor software.

"Growing recognition of the potential risks associated with microprocessor-based control is stimulating internationally harmonized standardization activities that address the extension of product safety standards to include requirements for safety management of products employing microprocessor-based controls," says Janet S. Flynn, UL research engineer. According to Flynn, who is responsible for developing investigation protocols for applying UL 1998, interest has come from U.S. organizations developing medical device regulations, OSHA, and the U.S. Voluntary Safety System. In Europe, interest has been expressed by those developing gas/oil, machinery, and medical device directives, she says.

The updated UL 1998 version addresses risks that may result from faults caused by software errors, including the following: design errors, such as incorrect software algorithms or interfaces; coding errors, including syntax, incorrect signs, and endless loops; timing errors that can cause premature or late program execution; induced errors caused by hardware failure; latent, user, input/output, range and other errors that are only detectable when a given value or set of conditions occurs; and failure of the system to perform any function at all.

Flynn is hopeful UL's voting process will be completed by fall, and official American National Standards Institute (ANSI) approval is received by this December.

Software suppliers conforming to UL 1998 receive a "Programmable Systems Certificate" specifying that their product meets the standard's requirements.

The level of difficulty varies from product to product and manufacturer to manufacturer. Some products pass all construction and test requirements from the start and get approval immediately. On the other hand if major enclosure changes or board changes are required, the approval may take longer. I have listed out the standards and generic test program that would be applicable. To provide more specific information a detailed product description will be needed.

UL approval on an industrial computer would require evaluation to UL 508, Industrial Control Equipment and if safety of personnel was at risk dependent on the computer and software UL 1998, Safety-Related Software could also be applied.

UL 508 would consist of evaluation of the product with regards to fire, shock and safety hazards. Typically the materials used would be required to posses electrical and mechanical ratings for the environment they were being used in. For a computer, plastics, printed wiring boards and power supplies would be of concern. Additionally, the user should not have access to certain voltage levels or moving parts.

UL 1998 is mainly directed at safety issues if the computer software malfunctioned. I am obtaining some information that will assist you.

The CE mark would require evaluation to the following Standards:

EN 61131-1, 2 and 3

EN 61131-X consists of safety and EMC requirements. Most of the safety issues would be addressed under UL 508 and UL 1998. The EMC requirements would require ESD, Radiated Susceptibility and Fast Transients per the 801 series of standards. Emissions testing similar to FCC Part 15 may also be required.

Please E-mail questions, comments and suggestions to webmaster@ltgservices.com

Please return to Compliance Corner


top of page to home page
Copyright 2000 LTG Services, Inc.
product-compliance-safety-testing ul-fcc-csa-ce-vcci-cul-al