IET logo
 
IET
Decrease font size
Increase font size
Topic Title: LPS Meets the Main Earth Bar
Topic Summary:
Created On: 19 June 2017 10:42 AM
Status: Read Only
Linear : Threading : Single : Branch
Search Topic Search Topic
Topic Tools Topic Tools
View similar topics View similar topics
View topic in raw text format. Print this topic.
 19 June 2017 10:42 AM
User is offline View Users Profile Print this message



sarandis10

Posts: 47
Joined: 21 November 2011

Gents

When do we need to bond the LPS to the MEB and when not?
what dictates the need of this bond?

Regards
 19 June 2017 10:58 AM
User is offline View Users Profile Print this message



John Peckham

Posts: 8713
Joined: 23 April 2005

When the LPS designer or contractor says it is OK to do so.

-------------------------
John Peckham

http://www.astutetechnicalservices.co.uk/
 19 June 2017 11:03 AM
User is offline View Users Profile Print this message



gkenyon

Posts: 4889
Joined: 06 May 2002

Originally posted by: sarandis10

Gents



When do we need to bond the LPS to the MEB and when not?

what dictates the need of this bond?



Regards
According to the Regs (wording as per BS 7671:2008+A3:2015) ... Always ... but in accordance with BS EN 62305. See Regulations 542.4.1 and 411.3.1.2. 411.3.1.2 includes the requirement "Connection of a lightning protection system to the protective equipotential bonding shall be made in accordance with BS EN 62305", and 542.4.1 tells you where to do it (the MET).

However, it's not always wise to connect the LPS to an electrical installation without integral SPDs (in both mains and telecom/data wiring).

If you are at all unsure, I'd recommend an LPS specialist look at it for you, rather than just connect it yourself.


IN ADDITION ... and quite importantly ... there is a potential issue with existing LPS installations.

Not all LPS on existing buildings comply with BS EN 62305. Older ones were designed in accordance with BS 6651, and connecting a BS 6651 LPS to the MET could well spell disaster for equipment in the installation !

If you are doing a re-wire of an installation in buildings with an older LPS, the issue you may have is that SPDs you may now be fitting to meet BS 7671 (or indeed BS 6701-related standards), may not be as effective unless the LPS is re-assessed in accordance with BS EN 62305, and appropriate modifications made.

Again, one for LPS specialists familiar with BS EN 62305.

-------------------------
EUR ING Graham Kenyon CEng MIET TechIOSH
G Kenyon Technology Ltd

Web-Site: www.gkenyontech.com

Edited: 19 June 2017 at 11:10 AM by gkenyon
 19 June 2017 11:04 AM
User is offline View Users Profile Print this message



gkenyon

Posts: 4889
Joined: 06 May 2002

Originally posted by: John Peckham

When the LPS designer or contractor says it is OK to do so.
And John's more succinct answer is probably far easier to understand than mine

-------------------------
EUR ING Graham Kenyon CEng MIET TechIOSH
G Kenyon Technology Ltd

Web-Site: www.gkenyontech.com
 19 June 2017 11:16 AM
User is offline View Users Profile Print this message



John Peckham

Posts: 8713
Joined: 23 April 2005

Graham

I was paraphrasing what it says in BS7430.

-------------------------
John Peckham

http://www.astutetechnicalservices.co.uk/
 19 June 2017 11:59 AM
User is offline View Users Profile Print this message



sarandis10

Posts: 47
Joined: 21 November 2011

Graham

thanks for the reply. it is a new building. basically a crossrail building.
on the schematics we have a bong from the MEB to the LPS. we where thinking to challenge this bond. there is on the specs as well.
i will ask the LPS Specialists to establish this connection.

Regards
 19 June 2017 01:16 PM
User is offline View Users Profile Print this message



OMS

Posts: 22211
Joined: 23 March 2004

Originally posted by: sarandis10

Graham

thanks for the reply. it is a new building. basically a crossrail building.

on the schematics we have a bong from the MEB to the LPS. we where thinking to challenge this bond. there is on the specs as well.

i will ask the LPS Specialists to establish this connection.

Regards


It's almost certainly required - but as Graham notes the LPS is only part of the equation - to be effective you also need the SPD's (of the correct type) at relevant points in the electrical installation

Given the population type, I'd have thought there was a particularly significant risk criteria to meet anyway so most of the required SPD's will be in place

Regards

OMS

-------------------------
Let the wind blow you, across a big floor.
Statistics

New here?


See Also:



FuseTalk Standard Edition v3.2 - © 1999-2017 FuseTalk Inc. All rights reserved.

..