RE: Certified Devices
The answer to question is the same.. I also came from a major PC vendor and shared some of the experiences of my collegues. The three vendors I gave you (Seagate, Maxtor Quantum) all put significant time money into EMC and test their drives at a component level. They all strive to meet the Class B levels OUTSIDE of a case with margin. Immunity - well outside of a case is asking a bit much!! Charles Grasso EMC Engineer StorageTek Tel:(303)673-2908 Fax(303)661-7115 -- From: Chris Herkey[SMTP:e...@attotech.com] Sent: Tuesday, April 22, 1997 6:46 AM To: emc-p...@majordomo.ieee.org Subject:Certified Devices I must apologize for my first submission of this message. I didn't specify clearly what I needed. Let me try again and let's see what we can come up with. Thank you to all that did respond, though. I found that info equally informative. Does anyone know where I might find a list of hard drives that are already mounted in enclosures and sold that way and are certified FCC class B and CE? Or perhaps someone knows of a manufacturer? I need singled-ended and differential SCSI drives... Thank you, Chris Herkey
Re: Certified Devices
Having once worked for a major PC company, I can tell you first hand that some disk drives can make a compliant Class B PC fail the Class B limits when the drive is installed. I even saw one drive make the PC fail the Class A limits! The purchase specification must specify that a Class B PC and the drive must comply with Class B limits. Also, you should qualify the drive by performing emissions testing of the PC. Otherwise, you can get caught with your pants down. Richard Woods -- From: Steve Chin To: emc-p...@majordomo.ieee.org Subject: Re: Certified Devices List-Post: emc-pstc@listserv.ieee.org Date: Monday, April 21, 1997 5:13AM 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
Certified Devices
I must apologize for my first submission of this message. I didn't specify clearly what I needed. Let me try again and let's see what we can come up with. Thank you to all that did respond, though. I found that info equally informative. Does anyone know where I might find a list of hard drives that are already mounted in enclosures and sold that way and are certified FCC class B and CE? Or perhaps someone knows of a manufacturer? I need singled-ended and differential SCSI drives... Thank you, Chris Herkey
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
Certified Devices
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
