ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by gfretwell - 03/28/24 12:43 AM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
1 members (Scott35), 260 guests, and 19 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 3 of 3 1 2 3
#97777 03/24/06 08:36 PM
Joined: Apr 2002
Posts: 7,381
Likes: 7
Member
Gfretwell:
Yes, the items you mention could 'break' the grd continuity of the water piping. And, yes, the GEC is my preferred choice, if I am doing the install.

However, FYI, the two 'offenders' in alarm inspections are:
NO earth ground.
NO bushing/grommet at cable entry into enclosure.

You may be shocked at some of the creativity I have seen.
#14 wrapped around a water pipe, similar to a 'choke'. Yes, it was green insul; no it was not terminated, just twirled around about 15-20 turns.
#14 under the 6/32 plate screw; a real work of art
#14 grn thru closet ceiling, not showing anywhere; pulled about 6" from above ceiling.
Small jumper from designated terminal to a sheetrock screw, that also secured the panel to the wall.
#14 grn shoved into the u-ground on the 'alarm receptacle'
and on and on.

Then there's the cable specialist, #10 grd from his splitter to a 2" pipe clamp....on PVC. Or, the lug tek screwed into the meter pan, or the downspout.

John


John
Stay up to Code with the Latest NEC:


>> 2023 NEC & Related Reference & Exam Prep
2023 NEC & Related Reference & Study Guides

Pass Your Exam the FIRST TIME with the Latest NEC & Exam Prep

>> 2020 NEC & Related Reference & Study Guides
 

#97778 03/24/06 11:01 PM
Joined: Jul 2004
Posts: 9,923
Likes: 32
G
Member
I still don't understand why you canb't just connect to the EGC in the circuit feeding the alarm panel. Are these cord and plug connected or hard wired?


Greg Fretwell
#97779 03/24/06 11:27 PM
Joined: Jan 2004
Posts: 1,507
G
Member
John- I'd agree with your second example for grounding an alarm panel but I'd have reservations about the first example and also with Greg's fastening to the grounding conductor of the alarm circuit. It's been years since the Code change that said you are to ground to the GEC, panel feeding the circuit or the water pipe within 5' of where it enters the building. See 250.130(C) for some examples. I know the alarm panel is not listed there but you get the idea.


George Little
#97780 03/25/06 09:42 AM
Joined: Jul 2002
Posts: 103
J
jes Offline
Member
George,
If you are referring to the typical residential combination fire/burglar panel with a plug-in low voltage power supply it is a Class II system and is not required to be grounded if supplied with a LISTED class II power supply (which is the case if it is a LISTED alarm system). The grounding of the panel is primarily for transient protection for the electronics. You are correct in requiring the installer to do so as it is part of the listing and labeling (110.3B)of the panel (and I have not seen one that wasn't so labeled). Typically the specified grounding wire is relatively small...like 16AWG, so a even a 1/2" metal pipe is a far better conductor than that to transients. Yes, there are questions about whether a metal water pipe in the area of the panel has continuity to ground at all. That too is an enforcement issue and to your discretion. Personally I try to locate panels close to the service and make use of the GEC or some common bonding point whenever possible. Also yes, I have dealt with the arguments of the ground connection 'bringing' the lightning to the system. I consider it a nonargument. The system must be installed as instructed. I cannot fix all the other grounding and bonding issues the may adversely affect the performance. If the system dies from a lightning strike it likely would have with or without the grounding...so just do it.

#97781 04/01/06 09:18 PM
Joined: Jul 2005
Posts: 56
P
Member
George:
I think they can attach the ground anywhere on the domestic water system. I think we can trust the electrician to check and make sure he has ground continuity. THe 5 foot rule applies to the bonding of the service equipment. This would be equipment grounding and would be simular to the requirements for a seperate building or structure where you are assuring the equipment ground part. Normally the 120 volt feed to these panels will contain an approved egc. Now George that is my opinion and I am going to stick by it.

Page 3 of 3 1 2 3

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5