help! electric problem

[manitu]

If you look in the lower left corner in the picture above , where it's burned, there is most likely two two wires like in the top right corner, cant tell from the picture. one comes from the breaker panel or another wall outlet , the other one continues to the next outlet. I guess thats why you have another outlet not working.

.manitu

 

[DarkLance]

get a "hotstick", a set of screwdrivers and some wire-strippers and you can have that outlet changed out in 15 minutes. make sure to cut back the melted wires at least 10cm to get nice copper and check all connections for proper contact.

Also, learn Ohm's Law

Volts = Current * Resistance (E=I*R)

And the practical application of Power (expressed as watts in our case)

Power = Voltage * Current (W=E*I)


This way you can figure out how much draw all of your electrical devices are using. 3 * 600w lights equal 1800 watts, on 220V that's 8.2 amps. most US households are wired with 14AWG wire rated to 15 amps, yours should be similar. If you plug an 1800 watts electric oven in... buzzzz!

if you apply Ohm's law above and know that heat creates additional resistance, you can see why a problem can go from bad to worse. This wiring does not care about safety, as resistance goes up and current stays the same, Voltage drastically increases to the point of failure.

Have a nice day!

EDIT: Having scrutinized the photo above a bit more, it looks like the top sets of wires feed the circuit, and the lower ones continue on further down the line (where I am assuming the grill was plugged in). I would be cautious that the wires may have melted beyond the fixture box into the wallspace. This would require that you re-wire the entire leg, and is ABSOLUTELY necessary, no attempt should be made to pigtail or otherwise "duct-tape" this problem.

 

[gaiusmarius]

@ audiohi yeah man, thank the Lord it didn't catch fire

@ coconaut Thanks man, upon rethinking the grill night i realized my bro used a different plug outlet then usual for the grill. i checked the grill and it runs at 1200watts lol. so it seems that's the explanation for the sudden melting, but it still doesn't explain why my fuse didn't blow. that's what's happened before now when someone overloaded the circuit with an iron or so. anyway thanks for your help.

@ medfinder yeah man

@ manitu thanks for the information, you guys are helping me understand whats up and how it happened.

@ DarkLance thanks man, very useful post for me. i did a extension cord temp solution yesterday only running 2 lamps on it for now. till it is all fixed. it's very good to know what seems to have happened, including the danger to the wire leading to the grill output. now i know what i need to tell the electrician mate when he gets here. btw the fuses are only 10 amp

peace and thanks to all

 

[manitu]

EDIT: Having scrutinized the photo above a bit more, it looks like the top sets of wires feed the circuit, and the lower ones continue on further down the line (where I am assuming the grill was plugged in). I would be cautious that the wires may have melted beyond the fixture box into the wallspace. This would require that you re-wire the entire leg, and is ABSOLUTELY necessary, no attempt should be made to pigtail or otherwise "duct-tape" this problem.

You must absolutely check the wires , and replace the whole leg if they are too short when you have cut off the burnt part.

About the cables.. The green/yellow wires on top , is earth , one from the breaker-panel , one goes on to the next outlet. The red(?) wires , top right corner , is a live wire. One from the breaker-panel , one goes on to the next outlet. Finally , the burnt wires.. I guess there are two wires of the same color there, most likely black or blue. In every country with 110/220V grid + Norway and Albania , this would be a live wire , a neutral in the rest of europe. same here , one wire comes from the breaker-panel , the other goes to your non-working outlet.

There is allways two or more interconnected terminals for each connections on these . You are NOT allowed to cram two wires in one hole so there is two and two terminals side by side ,so you have one spare of each , to connect the wires to the next outlet.

.manitu

 

[cocktail frank]

the wires going to the back of the receptacle are burnt.
the 2 plugs that are out must be the end of the line.
gonna have to get a replacement receptacle and change it.
ur looking like your in EU by the wiring.
everything is 220v, so the only wire of the 3 that HAS to go in the same place is the ground wire.
the 2 hots shouldnt matter, as long as they're not hooked up to your ground.

anytime you have a break in a circuit (plug/receptacle) your gonna get heat.
ive seen worse tho.
easy fix if your a lil mechanically inclined

 

[Avenger]

220 volts european is 220 volts to ground. one hot one neutral one ground


240 volts north american is two 120 volt legs to ground that gives you 240 volts between them. two hots one ground

 

[manitu]

220 volts european is 220 volts to ground. one hot one neutral one ground


240 volts north american is two 120 volt legs to ground that gives you 240 volts between them. two hots one ground

This is correct , unless you live in Norway or Albania , wich has it's own system.
We actually have three live wires , one ground , and NO neutral. If you meassure the voltage over any two live wires , you get 220. If you meassure over one live , and ground , you get 120V but you can't use the ground as neutral.

.manitu

 

[coconaut]

The big problem with the american system is that the neutral wire will carry the load of ALL the live wires. So , if you got two live wires and one neutral going to your garage , the neutral will carry as many amps as both the live wires together.

I don't think that's much of a problem, we have building codes here in North America that govern what gauge wire is to be used and where.
A 240v circuit does only have 1 neutral, but the wire is sized accordingly.
Interestingly however, more people die from 120v than any other voltage, they get shocked and may think they feel okay, and not seek out medical attention. Later resulting in a heart attack while they sleep.

 

[overbudjet]

This is actually a much safer system , than the american. The big problem with the american system is that the neutral wire will carry the load of ALL the live wires. So , if you got two live wires and one neutral going to your garage , the neutral will carry as many amps as both the live wires together.


.manitu

I am not a sparky but in american systeme the neutral only carry imbalance load let say 20 amp on 1 side and 15 on the other side
neutral will carry 5 amp.Don't take these for thruth always ask a sparky

 

[manitu]

I am not a sparky but in american systeme the neutral only carry imbalance load let say 20 amp on 1 side and 15 on the other side
neutral will carry 5 amp.Don't take these for thruth always ask a sparky

You may be right , but I think this calculation is a bit simplified. How many degrees separation between phases do you have in US? In europe , we use a 3 phase system , with 120 degree separation , and NO neutral wire.

But this is a bit outside the topic..

The important stuff here is: this is a 220V outlet , it has NO neutral wires , two live one , and one ground. you can switch the live wires around , if you like , but you can NOT use the ground wire , to make two 120V circuits.

.manitu

 

[cocktail frank]

overbudjet nailed it.
the neutral carries the imbalance of the hot phases.
with single phase, the math is just as easy as he stated.
the formula for neutral imbalance in 3-phase is another story.

manitu,
as far as degree seperation, our 3-phase is the same as yours.
360/3= 120degrees
single phase would be?
360/2= 180 degrees.
cake math

 

[madpenguin]

single phase would be?
360/2= 180 degrees.
cake math

Yea. That's why the neutral carries the imbalance of the load. L1 and L2 are 180 degrees out of phase with each other so they cancel each other other out.

You get the same thing with a 3 phase load with a neutral in it as well. A 3 pole breaker on a 120/208 wye 3 phase panel works the same way. phase A, B and C are all at 120v to ground. Pull 5A on each phase for 120v loads and the neutral see's 0A worth of current.

BTW, that receptacle is smokin'... Hopefully who ever originally wired that up left you enough wire in the box to where you can snip back some of that and then wire up a new receptacle. You can bet the wire insulation was damaged along with the actual receptacle.

 

[Avenger]

That's actually not true! European 220 V is still two live wires, but we don't use a neutral at all , so we can't make 120 V circuits.

i thought europe used 220v / 400v Y 3Ø?

Which measures 220 volts phase to ground and 400 volts phase to phase.

Everything I could find through google agrees with me.
http://wiki.answers.com/Q/Why_are_d...sed_in_the_various_countries_around_the_world

http://www.motionlabs.com/downloads/ConnectorChart.pdf

http://www.allaboutcircuits.com/vol_5/chpt_2/2.html


But I admit, I am not European, so i most certainly could be wrong.

 

[manitu]

Freaky!! We actually got our own system in norway , with three hot wires , and no neutral. I did'nt know that the rest of europe has another systemwith 2 hot wires and one neutral.,
I have to look over my electrical posts to see if i need to clarify anything . Luckily , we don't talk much about 3-phase here.

Since the phases is 120 degrees apart , and not 180 , you only get 220V between two phases and there is absolutely no neutral wire in our system.
I am quite shure our 3-phase is 380 volts , but then again , hasn't used 3-phase since school.

I don't see why you americans would have two phases 180 degrees apart (using neutral as reference).. where would you put the third?? I guess you transfer 3-phase electricity on the same power-grid as the ordinary houses are connected to?

Here , most houses has a 3-phase main breaker panel. When you plan a electric installation in a house , you try to spread the load evenly between the three possible 2-phase connections.

.manitu

 

[Avenger]

Thought you might find this interesting manitu:
http://www.tkk.fi/Misc/Electronics/wire_mains.html#europe

 

[manitu]

Thought you might find this interesting manitu:
http://www.tkk.fi/Misc/Electronics/wire_mains.html#europe

Yes , absolutely! This is our system:

Other special cases: There are also some special wiring used in some places. Another much rarer scheme is 230V between phases and no neutral in the supply. Houses are then fed two phase wires, neither of which is necessarily anywhere near earth potential. This is used in at least in Norway coutries in some locations. Also in some places in Belgium three phase 220 across the phases (= 127 phase to earth/neutral) is used on older domestic dwellings (new installations are 400/230 3 phase, neutral, earth). For this reason all Belgian fuseboards (whether actual fuses or circuit breakers) protect both current carrying wires irrespective of supply type.

I've been looking at my posts , and I dont think I've done any damage. I try to stay away from 3 phase Q's.. Boy, I'm glad I didn't recomend anyone to run 120V stuff between a live wire , and the lightning rod. It actually works at my place....DO NOT DO THIS AT HOME!!!!!

.manitu

 

[gaiusmarius]

update

thanks guys, you given me a clear picture of what i need to do. the electrician seems to be out of town, so i'm thinking i'll tackle it myself. will be checking to see the condition of the wires leading to the melted part, will also check the inside of the grill outlet to see if it took any damage, as well as the other outlet that stopped working. if not and the wire is long enough after cutting damaged part off i can leave the old wire in there right? i'm hoping this is the case, as i feel uncomfortable about removing and replacing the wire inside the walls, as i'd worry if i was hooking them back up the right way. obviously i'll take all the fuses out before i start.

for now all is running on an extension cable run from the kitchen washing machine outlet. but this is only temporary, i want the outlets fixed anyway, just can't have a normal electrician in there till the run is over.

thanks again for all the responses

 

[manitu]

Yeah , If the old wire is long enough after you cut off the damaged bits you can reuse it.

If you have to replace the wire , just tie he new wire to the old wire ,and just pull the old wire out from the oposite side. That way , when the old is out , the new wire is in place.

.manitu

 

[DarkLance]

best way to check is with a voltmeter, if you get significant resistance (anything more than 1-200 Ohms) you know the wire's bad.

For 16 AWG (~1,31mm^2) copper wire, there is 0.818 Ohm's per 100 ft, including any contacts you should see a very low resistance measurement.

A visual check should suffice if you have isolated the circuit and are able to definitively located the faults. In your case it should be only that one outlet. Otherwise, you seem to be on the right track. GL mate

 

[madpenguin]

Umm... Don't forget to tell him to turn off the circuit before checking for resistance....