What happened

[davyfireball]

I have 3 outlets in a series. The middle 1 didn t work. I took out all screw in fuses. Put meter on continuity and probed the outlet to the right. It registered continuity on both neutral and positive.
So I tried the left it had continuity on both neutral and positive . So I took a neutral wire off bad outlet . Checked it for continuity against the other plugins it was ok . Hot & neutral were separate.
Craziest thing I ever saw. Changed middle plugin. Everything works. Why didn t it blow fuse.

 

[Dennis Minn]

Something else plugged in that
circuit, like a lamp.

D.

 

[davyfireball]

(quoted from post at 20:00:29 08/24/22) Something else plugged in that
circuit, like a lamp.

D.

No - had electric off

 

[Janicholson]

open circuits (non working) don't blow fuses or breakers. I am not sure what test you made with contenuity.
but AC voltage between the two slots would tell power there. one of the slots should show power to the ground
round terminal the other not. Jim

 

[Steve@Advance]

Like Jim said, open circuits don't blow fuses.

And testing with an ohm meter is not reliable. A weak connection may show good with an ohm meter, but go open
when under load. Even the slightest disturbance (messing with the outlet) can make a bad connection
reconnect, only to fail again when under load.

The best way to track down a faulty receptacle is to leave the power on and have something like a lamp
plugged in a dead receptacle on the circuit. Carefully start pulling receptacles out, being aware a wire may
pull out of the back when you do, or the light may come on. Either way, you will know when you are in the
trouble spot.

 

[davyfireball]

(quoted from post at 23:51:53 08/24/22) Like Jim said, open circuits don't blow fuses.

And testing with an ohm meter is not reliable. A weak connection may show good with an ohm meter, but go open
when under load. Even the slightest disturbance (messing with the outlet) can make a bad connection
reconnect, only to fail again when under load.

The best way to track down a faulty receptacle is to leave the power on and have something like a lamp
plugged in a dead receptacle on the circuit. Carefully start pulling receptacles out, being aware a wire may
pull out of the back when you do, or the light may come on. Either way, you will know when you are in the
trouble spot.

Thanks davy

 

[John T]

Mornin Davy, good question Why didn't it blow fuse

FWIW I agree with the other fine sparky gents (great minds think alike maybe??? lol)

To blow a fuse requires a SHORT OR TOO LOW RESISTANCE CIRCUIT (and path for excess current flow)......
NOT AN OPEN CIRCUIT (no circuit path, no current, no blown fuse)

Next an OHM METER can measure the resistance of a circuit and also tell you if a circuit is like
completely OPEN (infinite ohms). A cheaper meter is not perfect accurate at low resistances...

Finally, a VOLT METER can measure the voltage available at say an outlet: IE you hang a volt meter on and
it reads 120 VAC and you think no problem, why doesn't this darn outlet work when I plug in an appliance
?????????????? ..

HERE CAN BE WHY if in that circuit there's a bad/loose/resistive connection or splice etc and since a
quality Volt Meter has very high internal resistance so there's like no current flow through that
bad/loose/resistive connection/splice THERES NO V = I x R Voltage Drop, which means the meter may still
read 120 Volts while an appliance would still NOT work.

It takes a short (or too low resistance) circuit to blow a fuse, while an open circuit may render
something inoperative yet NOT blow a fuse. A mis-wired or bad connection at even a perfectly good outlet
can make it inoperative.

Glad you got it fixed

Best wishes to all here have a good day now

John T

 

[dr sportster]

Open -- not a short to trip breaker -- no fault current

 

[Stephen Newell]

The outlet wouldn't blow a fuse if it was defective or damaged internally. It would only blow the fuse if the neutral or ground came in contact with the hot
line.

 

[miangus]

Was it one of those pesky receptacles with the push in connections on the back?

 

[used red MN]

It seems like you have gotten your answer. My question
is ..JAN did sort of ask this.. what points did you check
continuity between? You said ..Put meter on continuity
and probed the outlet to the right. It registered
continuity on both neutral and positive.. the question is
continuity to what, where did you place the opposite
lead? A continuity test is for checking ..electrical
conductivity of a circuit or an electronic part between
two points.. You tell us point A but an explanation of
point B is not given. You are correct that there should
be no continuity between the power and neutral sides
of the receptacle. That was more likely a meter error.
However, if one of the plugs in the circuit is a GFI that
would cause a meter to show continuity there.

This is all covered by John T in his explanations. But
you would need to know IF you may have been making
an incorrect connection of your meter to glean how to
make it correct when using your continuity meter next
time. In other words the ..IF.. above is because you do
not tell us point B, to know if you were making a
legitimate test. .. ..Now when I reread this maybe you
were only testing ..across or between.. the power and
neutral.. of the receptacle, by using ..both.. that
indicated to me two separate tests when maybe it was
not. Sorry, this may have been all unneeded garble.

 

[huntingreen2day2]

Could be something else on the circuit causing you to get a continuity reading . Example light bulb ,radio,tv,, smoke detector etc.

 

[504]

Just thinking out loud, did the jumper between the two
outlets on the bad pug fail. That could give you power to
the next outlet and none to half of the middle outlet.