Hi Marko,
I'm curious what measures you and others take to protect against
ESD, Lightning, etc when implementing a multi-point bonding scheme of signal
ground to frame/chassis ground. I can definitely see the advantages for
EMI.
Thx,
Joe
-----Original Message-----
From: Marko Radojicic [mailto:[email protected]]
Sent: Tuesday, September 10, 2002 2:22 PM
To: 'Joe Finlayson'; 'John Juhasz'; 'Dorin'
Cc: 'EMC-PSTC - forum'
Subject: Grounding architectures for COs
Greetings,
Bonding of the different system grounds is, surprisingly, a very involved
topic.
Historically, CO equipment in North America (NA) has been Star-IBN (Isolated
Bonding Network) sometimes referred to as ISG (Isolated Signal Ground). (I
won't go into all the reasons behind it.)
In Europe (EU), a Mesh-IBN, sometimes referred to as Common Bonding Network
(CBN), is used.
Battery Return is also problematic. In NA, it *must* be held isolated from
CG/FG. In the EU, it *must* be bonded to the CG/FG!
Both can be effectively deployed but the EU version is more robust to
violations.
In terms of pros and cons, multi-point bonding the signal ground (SG) and
chassis ground (CG) is, by far, the most effective architecture for EMC
applications as it offers EMI currents a lower impedance path back to the
source. For all my high-speed, high-power designs, we've implemented this
multi-point SG to CG architecture.
The downside to this strategy is that you can no longer be Star-IBN
*compliant* however you will be Star-IBN *compatible*. NA ILECs (Verizon
included) have been accepting this grounding architecture for over a decade
now so there is no new ground that you'll have to turn over.
Hopefully this explanation has cleared up the situation a little. For
further reading, I'd recommend ITU (formerly CCITT) K.27 (the granddaddy of
grounding documents - Figure 1 is invaluable) as well as ETS 300 253
(Earthing and Bonding for Telecom).
Cheers,
Marko
-----Original Message-----
From: Joe Finlayson [mailto:[email protected]]
Sent: Tuesday, September 10, 2002 9:03 AM
To: 'John Juhasz'; 'Dorin'
Cc: 'EMC-PSTC - forum'
Subject: RE: Inrush and EN61000-3-3
John & Dorin,
Please clarify as I am not aware of a requirement to isolate Signal
Ground from Frame Ground. Please reference GR-1089-CORE, Section 9.6.2 as
well.
Thx,
Joe
-----Original Message-----
From: John Juhasz [mailto:[email protected]]
Sent: Tuesday, September 10, 2002 11:12 AM
To: 'Dorin'
Cc: 'EMC-PSTC - forum'
Subject: RE: Inrush and EN61000-3-3
Be careful Dorin. For Central Offices, they need to be isolated.
John A. Juhasz
GE Interlogix
Fiber Options Div.
Bohemia, NY
-----Original Message-----
From: Dorin [mailto:[email protected]]
Sent: Tuesday, September 10, 2002 9:12 AM
Cc: 'EMC-PSTC - forum'
Subject: Re: Inrush and EN61000-3-3
Hi,
I am looking for a comparison, pros and cons, on the signal ground
connected versus not connected to the chassis in a telecom system. Any
help is appreciated.
Thanks,
Dorin
-------------------------------------------
This message is from the IEEE EMC Society Product Safety
Technical Committee emc-pstc discussion list.
Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/
To cancel your subscription, send mail to:
[email protected]
with the single line:
unsubscribe emc-pstc
For help, send mail to the list administrators:
Ron Pickard: [email protected]
Dave Heald: [email protected]
For policy questions, send mail to:
Richard Nute: [email protected]
Jim Bacher: [email protected]
All emc-pstc postings are archived and searchable on the web at:
http://ieeepstc.mindcruiser.com/
Click on "browse" and then "emc-pstc mailing list"
-------------------------------------------
This message is from the IEEE EMC Society Product Safety
Technical Committee emc-pstc discussion list.
Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/
To cancel your subscription, send mail to:
[email protected]
with the single line:
unsubscribe emc-pstc
For help, send mail to the list administrators:
Ron Pickard: [email protected]
Dave Heald: [email protected]
For policy questions, send mail to:
Richard Nute: [email protected]
Jim Bacher: [email protected]
All emc-pstc postings are archived and searchable on the web at:
http://ieeepstc.mindcruiser.com/
Click on "browse" and then "emc-pstc mailing list"
-------------------------------------------
This message is from the IEEE EMC Society Product Safety
Technical Committee emc-pstc discussion list.
Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/
To cancel your subscription, send mail to:
[email protected]
with the single line:
unsubscribe emc-pstc
For help, send mail to the list administrators:
Ron Pickard: [email protected]
Dave Heald: [email protected]
For policy questions, send mail to:
Richard Nute: [email protected]
Jim Bacher: [email protected]
All emc-pstc postings are archived and searchable on the web at:
http://ieeepstc.mindcruiser.com/
Click on "browse" and then "emc-pstc mailing list"
-------------------------------------------
This message is from the IEEE EMC Society Product Safety
Technical Committee emc-pstc discussion list.
Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/
To cancel your subscription, send mail to:
[email protected]
with the single line:
unsubscribe emc-pstc
For help, send mail to the list administrators:
Ron Pickard: [email protected]
Dave Heald: [email protected]
For policy questions, send mail to:
Richard Nute: [email protected]
Jim Bacher: [email protected]
All emc-pstc postings are archived and searchable on the web at:
http://ieeepstc.mindcruiser.com/
Click on "browse" and then "emc-pstc mailing list"
