ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Where is Everyone?
by gfretwell - 06/20/21 10:53 PM
Happy Father's Day!
by Bill Addiss - 06/19/21 04:16 PM
A Risky Setup
by timmp - 06/18/21 08:08 PM
Conduit over Vinyl Siding
by Jim M - 06/16/21 08:30 PM
Updated Forum Software
by Admin - 06/15/21 10:23 AM
New in the Gallery:
2020 - 2021 Winter Project
2020 - 2021 Winter Project
by Bill Addiss, April 29
Garden 2021
Garden 2021
by Bill Addiss, April 26
Who's Online Now
0 members (), 15 guests, and 17 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Joined: May 2001
Posts: 376
F
frank Offline OP
Member
Is there any functional difference between a gfci receptacle and a gfci breaker.I know gfci receptacles are calibrated to trip at 5ma?thanks

Joined: Jan 2003
Posts: 4,391
I
Moderator
Both have approx. 5ma trip levels


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Joined: Sep 2001
Posts: 806
N
Member
In my experience, GFCI breakers exhibit more of a tendency toward nuisance tripping than the receptacle types, particularly when feeding a very long branch circuit run, or just about any length of old cable. I presume this has to do with leakage to ground (either resistive or capacitive) in the cable run.

Putting the GFCI at the point of use avoids tripping from these leakage currents. The receptacles are also generally less expensive than the breakers....

Joined: Oct 2004
Posts: 72
B
Member
So how do you get

"(either resistive or capacitive) in the cable run."

I could see voltage drop but I don't know how you get reactence in just a cable run?

Joined: Sep 2001
Posts: 806
N
Member
You have capacitance between any 2 insulated conductors in a raceway or cable, as well as between the conductors and ground. A capacitor is simply 2 conductors (the copper wires or metal raceway/armor) separated by an insulating dielectric (the wire insulation). The potential leakage gets higher with a longer cable run (adds more capacitance) or older, degraded insulation (lowers leakage resistance).

If the resistance gets low enough or the capacitance gets high enough, sufficient leakage current can be present to trip the GFCI, or to lower the "overhead", so additional leakage below the usual 5 mA will be enough to cause a trip.


[This message has been edited by NJwirenut (edited 03-27-2005).]

Joined: Dec 2004
Posts: 1,064
D
Member
Tx, NJwirenut.

Never really fully understood leakeage current like that before.

Good explaination.....


Dnk.....

Joined: Oct 2004
Posts: 72
B
Member
Vary good, thank you. [Linked Image] I feel lerned now.


Link Copied to Clipboard
Featured:

Tools for Electricians
Tools for Electricians
 

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
The Watt Doctor
The Watt Doctor
Mont Belvieu, TX
Posts: 437
Joined: December 2001
Top Posters(30 Days)
Trumpy 10
Admin 10
Popular Topics(Views)
280,448 Are you busy
213,527 Re: Forum
200,406 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5