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Conference netcad::hub_mgnt

Title:DEChub/HUBwatch/PROBEwatch CONFERENCE
Notice:Firmware -2, Doc -3, Power -4, HW kits -5, firm load -6&7
Moderator:NETCAD::COLELLADT
Created:Wed Nov 13 1991
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:4455
Total number of notes:16761

2400.0. "DEChub 90 power supply questions" by CGOOA::CRICK () Tue Jun 20 1995 15:40

    I have a customer that wants some detailed information on the DEChub 90
    power supply.  He wants to know how we tested for ground fault
    isolation and what the impedance is.  Does the power supply use a
    transformer for isolation?  
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2400.1Ethernet port/power supply isolation?CGOOA::CRICKWed Jun 21 1995 15:345
    Further to my original note, I have contacted the customer again and got
    clarification on what he was really looking for.  He is concerned that
    a power supply failure could cause a DC or AC voltage to appear on a
    Ethernet segment.  I assume that we have some form of isolation between
    the power supply and the Ethernet ports.  Can someone verify that?
2400.2Most or all LAN standards *require* isolation of some type...NETCAD::BATTERSBYWed Jun 21 1995 15:4210
    <-----RE: 2400.1
    Most Ethernet port designs that I know of definitely do have
    isolation within the physical layer logic per the appropriate
    IEEE standard.
    For example both the AUI and TP ports of the HUB DECswitchs and PEswitch
    products have isolation transformers in the physical layer logic.
    This is done for the express reason such as stated in the previous
    note.
    
    Bob