ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat Box
Recent Posts
Lock-down Thread
by HotLine1 - 02/24/21 03:25 PM
You will never guess
by HotLine1 - 02/22/21 01:34 PM
New tool
by SMOKEYBOB - 02/15/21 04:59 PM
Split Bus Breaker Panel
by gfretwell - 02/15/21 02:30 PM
Sierraplex recpts
by gfretwell - 02/15/21 02:27 PM
New in the Gallery:
Facebook follies, bad wiring
FPE in Germany pt.2
Who's Online Now
2 registered members (HotLine1, Scott35), 24 guests, and 21 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Gfi's and testers. #169841 10/17/07 08:17 PM
Joined: Mar 2002
Posts: 179
D
derater Offline OP
Member
Could use some insight on this; gfi receptacle trips with 'test' button, but not with a gfi tester. New type that supposedly won't work if wired wrong. Tester is ok. Ideas ?

Work Gear for Electricians and the Trades
Re: Gfi's and testers. [Re: derater] #169843 10/17/07 08:29 PM
Joined: Jul 2004
Posts: 9,568
G
gfretwell Offline
Member
No ground?


Greg Fretwell
Re: Gfi's and testers. [Re: gfretwell] #169846 10/17/07 09:32 PM
Joined: Oct 2007
Posts: 56
S
SP4RX Offline
Member
I agree with Fretwell. I think that the gfi tester works by allowing a small amount of current to flow from the hot conductor through a resistor to the grounding conductor. So if you have no ground connection at the gfi the tester's ground prong wouldn't have a good return path for the simulated ground fault.
This doesn't mean that the gfi won't work as intended though since it normally compares line current to neutral current, with no need for a ground.
Perhaps you could verify it's correct operation by unscrewing the gfi and, using a separate wire, make a temporary connection to a good remote ground point and then try your tester again?

Shawn.

Re: Gfi's and testers. [Re: SP4RX] #169858 10/18/07 11:54 AM
Joined: Jun 2007
Posts: 301
J
JValdes Offline
Member
The neutral carries the same current as the hot conductor. A ground would be necessary for the GFCI to work properly.

Re: Gfi's and testers. [Re: JValdes] #169859 10/18/07 12:12 PM
Joined: Mar 2005
Posts: 1,213
S
SteveFehr Offline
Member
Originally Posted by JValdes
The neutral carries the same current as the hot conductor. A ground would be necessary for the GFCI to work properly.
The GFCI will still work properly without a ground (hence its acceptability in ungrounded retrofit appliations) but the GFCI tester wouldn't work, as it can't shunt a small amount of current to ground if there's no ground to shunt to. Standing in a puddle and sticking a wet finger into the receptacle aught to do the trick, though. But it's certainly not recommend as the consequences if the test fails are potentially rather dire...

Last edited by SteveFehr; 10/18/07 12:13 PM.
Re: Gfi's and testers. [Re: SteveFehr] #169865 10/18/07 02:56 PM
Joined: Mar 2002
Posts: 179
D
derater Offline OP
Member
Thanks all. That's the case, no ground.


Featured:

2020 National Electrical Code
2020 National Electrical
Code (NEC)

* * * * * * *

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

 

Member Spotlight
CharlieE
CharlieE
Indianapolis
Posts: 201
Joined: April 2004
Show All Member Profiles 
Top Posters(30 Days)
MCosta 3
Popular Topics(Views)
275,345 Are you busy
209,205 Re: Forum
196,511 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.3