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I am looking for a copy of EN 50027 Crimping Standards. Can someone suggest a local source where I might be able to purchase this document? Thanks in advance Rick Busche rbus...@es.com
Re: Certified Devices
Chris, none of the hard drive manufacturers certify that their mechanisms are Class B compliant. Just like a motherboard or power supply, the hard drive is considered a component. My company produces a wide variety of storage peripherals, and most of the drive manufacturers in the past have pretty much left companies like mine in the lurch where EMC compliance is concerned. They have been getting better (from a customer standpoint) at this lately, so most of what you'll find out there now will pass the Class B limits with some margin, provided you have a good host to start with, good power supplies, and reasonable filtering/shielding. None of the views expressed in this message intentionally represent those of any being, living, dead, or corporate. They are mine and mine alone. Steve Chin Compliance Engineer StreamLogic Corp. Menlo Park, CA, USA sc...@sledgehammer.com Chris Herkey (e...@attotech.com) wrote: Does anyone know where a list of hard drives that are certified class B and CE might be found? Or perhaps someone knows of a manufacturer? I need singled-ended and differential SCSI drives... Thank you, Chris Herkey
Re: IEC320 and Double insulation
Hi Hans: The IEC 950/EN 60950 definition for a Class I product is: Equipment where protection against electric shock is achieved by: a) using BASIC INSULATION, and also b) providing a means for connecting to the protective earthing conductor in the building wiring those conductive parts that are otherwise capable of assuming HAZARDOUS VOLTAGES if the BASIC INSULATION fails. Notes 1 CLASS I EQUIPMENT may have parts with DOUBLE INSULATION or REINFORCED INSULATION, or parts operating in SELV CIRCUITS. 2 For equipment intended for use with a power supply cord, this provision includes a protective conductor as a part of the cord. Your product DOES use basic insulation. Your product IS provided with a means for connecting to the protective earthing conductor in the building wiring. (The fact that the terminal is not at the supply end of the cord is irrelevant.) The construction you describe is IMPLIED to be Class I by use of the two-wire plus ground IEC 320 connector. I believe there is a requirement either in IEC 950 or IEC 536 that if a protective grounding terminal is provided, the equipment is considered Class I even if it is Class II construction throughout. You cannot apply the double-insulated symbol to a product with a grounding terminal. Best regards, Rich ps: The power cord plug is NOT Class 0. Class 0 is a product with only Basic Insulation and for use only in an earth-free insulating environment which provides protection against electric shock in the event of a fault in Basic Insulation. At one time, the Euro authorities believed the normal indoor environment to be an earth-free insulating environment, which then qualified two-wire, basic-insulated products for use in such an environment. Some years ago, Class 0 construction was deemed unacceptable in Europe (although it appears to be acceptable in Japan).
