Broken Electric

[Cerulean Talon]

I live in a house that was built in 1912, was updated in 1950, and in the past 4 years have done renovations. Recently I replaced 4 of the 5 circuit breakers on the right side of my breaker box. Three had stopped working after flickering on and off for a while and the 4th was starting to do the same thing. Now all wiring on those new breakers will cut off for a few seconds or more several times a day. Can anyone help me figure this out?

Thanks!!!

[Snoonyb]

Your original problem may not have been worn or malfunctioning breakers at all, but a loose connection to one side of the main or buss bar.

Service feeds occur in two general manners. Directly from the bottom of the meter hub to the main breaker hub which is also connected to the two hot buss bars through the main and energises/disconnects them.

Directly from the meter hub to the screw connections on the breaker.

These connections fail at a greater rate if your conductors from the meter to the breaker are aluminum.

Call a qualified electrician.

[Cerulean Talon]

Thanks, Snoonyb!

[HayZee518]

Real old panels had tinned copper wire for meter wiring. The outer jacket was of a waxed jute fiber material. When aluminum came on the market the panels were still rated at copper only. Service techs were torqueing the main breaker and bus bolts to copper specs not aluminum. Copper has the property of offering some resistance [not electrical resistance] to bolted conductors. Aluminum is not as dense as copper so doesn't exihibt this resistance to torqueing. Also in the early days they never heard of anti oxidants. Immediately after stripping aluminum wire it starts to form an aluminum oxide coating which is an insulator and is a resistance [electrical] at the joint. Service entrance cable, normally 10 gauge stranding for 4/0 SEU will substantiantly oxidize and form a higly resistive joint if not prepared by wire brushing and treating with No-Alox or other anti-oxidant. Also the newer panels are rated Al-Cu at their terminations. Use copious amounts of the anti oxidant and torque the bolts to recommended specs. This will assure the cable springs back a little to form a low resistance joint.
Over tightening won't solve a problem, might make it worse.
Also if your bus stabs are all aluminum, using some anti-oxidant on the breaker stabs wouldn't hurt either.

[Cerulean Talon]

Thanks for all the detail. I like to know who, what, where & why. This is my first home. I've helped build and renovate a couple others, but never came across this issue. Again, Thank you!!