Conformity Magazine - November 2007 - (Page 29)

When in doubt over the required standards for a particular machine, an NRTL should be consulted to help define the applicable standards and requirements. The Field Evaluation Preliminary Inspection The preliminary inspection is intended to assess the overall construction and safety of the machine to the relevant technical standards. During the preliminary inspection, it is not necessary to assess aspects of compliance that are unique to the final installation site. So the preliminary inspection may be performed at the manufacturers’ location as well as at the final installation site. Documents Required The machinery manufacturer should prepare for the preliminary inspection by collecting the documents that the NRTL inspector will require. The required documents (which need to be provided in copies the inspector may keep for the NRTL records) are: • A copy of the safety warnings and instructions from the operators manual; • A copy of the electrical schematic(s) for the machine; • A list of safety-relevant components (which are all components connected to hazardous voltages or which are used in safety-related circuits such as e-stops or interlock controls), including the manufacturer, the part number, and the NRTL approval for the component3. Constructional Requirements During the preliminary inspection, the construction of the machine is assessed per the requirements of the relevant technical standards. All constructional requirements of the standards must be complied with. In general, the following areas are examined: • Examination of the incoming supply conductors and the means of disconnection from the electrical supply; • Examination of methods of providing protection from electric shock; • Examination of over-current and overload protection methods; • Examination of the grounding system; • Assessment of control circuits and functions; • Examination of safety functions like emergency stop and safety interlocking; • Examination of operator interfaces and control devices; • Assessment of the mounting and placement of control equipment; • Examination of the suitability of supply conductors for the rated loads and conditions of use; • Assessment of wiring practices; • Assessment of warning markings and safety-relevant markings on the machine. All non-compliances with construction requirements are documented in an initial report and provided to the machine manufacturer for review. The NRTL can then discuss various methods of modification to allow for the most efficient correction of the problems by the machine manufacturer. Component Requirements In general, during the construction evaluation, the NRTL will assess and confirm that all safety-relevant components are NRTL-approved, and used within their documented ratings and usage requirements. Safety-relevant components are: • All components attached to hazardous voltages (60VDC or 35Vrms or greater); NOVEMBER 2007 CONfORMity 29 http://www.fair-rite.com http://www.fair-rite.com

Table of Contents Feed for the Digital Edition of Conformity Magazine - November 2007

Conformity - November 2007 Contents Editor’s Note Commission Sets Date, Terms for 700 MHz Auction FCC Reaffirms Roaming Obligations Commission Moves to Improve USF Management FCC Proposes Fines for Violations of E911 Handset Requirements Commission Levies $1 Million Plus Fines for Unsolicited Fax Advertisements GR-3150 - Lithium Battery Certification Levels Based on Criteria for General Product, Safety, and Performance, Part 2 ESD Open Forum Machinery Field Evaluation for the United States Validation, Verification, and Immunity Testing Techniques for EMC for Functional Safety Thermal/EMC Simulation Addresses New Mechanical Design Challenges Product Safety Equipment Buyer’s Guide FCC Releases Report on Telephone Numbering Resource Utilization Canada Still Has PCS Spectrum to Assign Updated Standards List for the EU’s Medical Devices Directive Updated Standards List for EU Directive on Active Implantable Medical Devices Call for Papers for the 2008 EOS/ESD Symposium Announced Mobile Phone Use in Hospitals May Be Dangerous CPSC Actions in the News IEC Standards Update UL Standards Update Telcordia Standards Update From Our “You Can’t Make This Stuff Up” Department Product Reviews Looking Back: Items from Past Issues of Conformity Upcoming Events Advertisers

Conformity Magazine - November 2007

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.