wlearning

I will start with giving my level of understanding:

• good foundational knowledge of DC auto electrical troubleshooting.
• understand Ohm's law.
• understand safety precautions and procedures.
• have limited experience with AC current/circuits.

Here are the symptoms:

• A 20A breaker blew a few times and then failed. I replaced the breaker.
• One pair of receptacles on this circuit no longer works. Everything else powered by this circuit works fine.
• These receptacles are located on opposite sides of an interior wall and are supplied from the same junction box.
  • The receptacle on one side of the wall is rarely used.
  • The other receptacle powers only a desktop computer, monitor, inkjet printer, and two lamps with 60 watt bulbs.
  • This configuration has been trouble free for years.
• All outlets show 110v with a circuit tester, but fail to power a known good drop light with a 100w bulb.

Here is what I have checked:

• visual inspection of wiring and connections for both receptacles
• visual inspection of all wiring for this circuit in the attic
• visual inspection of all wiring and connections in the junction bos for this circuit
• visual inspection of all wiring and connections in the breaker box.

I found no loose connections, evidence of heat, or evidence of corrosion. Logic tells me that I am getting voltage, but not amperage to carry a load. What else can I check before calling a professional?

Thanks for your helpful advice.
wlearning

wlearning

I see no replies yet. Did I ask the question wrong? Is more information needed?

Please respond.

Blue Jay

You have a high joint some place, plug your drop light in and check voltage to ground this will let you know if it is the hot or nuetral that has the problem. If you do not get correct voltage at the plug then check coming off the breaker. Since it had tripped the breaker orignally you have a bad spot some place that you have not checked yet.
Good Luck

wlearning

Thanks Blue Jay,

This will give me more concrete troubleshooting. It will be the weekend before I can spare the time to check it out. I will post feedback.

JoeD

Sounds like a loose neutral connection. Problem could be in a working device box.

CharlieO

You say "All outlets show 110v with a circuit tester, but fail to power a known good drop light with a 100w bulb".
What type of tester are you using?
Are you removing the outlet plate and testing the wires or using a plug in tester?
If you are testing the wires going to the outlet and they show 110v, and you plug in the drop light and it does not work, it is probably a bad outlet and it feeds the other outlet so neither one works.
Charlie O.

wlearning

Thanks for the replies JoeD and CharlieO.

JoeD: I have to wait for the weekend to explore that further.

CharlieO: I used a LED tester with probes inserted in the outlets. The tester lights LEDs to indicate 110v or 220v. The tester indicated 110v, but the drop light failed to light. I did not test the wires leading to the receptacles. I was thinking that power at the outlets confirmed power to the outlets. -- but -- this is a learning process for me. i have room to learn through this exercise.

I will use the information provided so far to expand my troubleshooting. I will post back with findings and/or success.

thanks again.
wlearning

Blue Jay

WLEARNING You will need a meter to check the voltage, the LED tester will light on micro amps and would probably show voltage between the hot and your hand. Cute items but I would not have one for myself if it was given to me.

wlearning

Sorry for the delay in posting back ... My troubleshooting was not complete when I ran into an electrician I knew years ago. He came over to troubleshoot the problem.

While he had his meter hooked up, the power for the entire house went out momentarily. (There were wind gusts up to over forty miles per hour at the time.) The incoming lines were whipping around fiercely. He watched for a few minutes, and the power was interrupted momentarily again.

He recommended calling the power company to replace the lines. (They are over sixty years old and have the old school ceramic insulators where they tie into the house. In places the insulation has fallen off the lines.) ... anyway ... We are waiting for the power company to replace the lines before continuing with checking the interior wiring.

Thanks everyone.