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odd problem at school

Posted by matt-kuhar (My Page) on
Sun, Apr 11, 10 at 0:54

im just wondering what would cause the left prong on a three prong power tool to blacken and melt the plug on the cord of the tool. and yes this is the factory plug not a replacement. my school just bought a new sander and a new band saw and they both blackened when they were used just like the older tools. again the prong is the one that goes in the left side of the outlet when plugged in. thanks and sorry for writing so much, matt


Follow-Up Postings:

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RE: odd problem at school

Bad contact in the wall receptacle.


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RE: odd problem at school

Yup. Old or cheap receptacle that the "grip" has gone weak.

Very common problem.


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RE: odd problem at school

ok i could understand that. but the thing is that they just replaced all the outlets in the room last school year. and all plugs fit into the outlets very firmly. so im still not sure what could be causing this.


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RE: odd problem at school

Physical contact ("all plugs fit into the outlets very firmly") and electrical contact are not mutually inclusive. It is entirely possible for a plug to fit very firmly into a receptacle and have inadequate electrical contact.


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RE: odd problem at school

ok. but wouldnt it turn both of the prongs on the plug black? or am i missing something here. we also tried a jig saw we got today in another wing of the school and the same blackning of the left prong occured when only used for about 5 minutes.


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RE: odd problem at school

It actually wouldn't turn both black if in fact that is the problem. It would only arc and blacken where the connection is loose. It's not very common to replace a receptacle and for this to happen, but sometimes during instalation I have seen people take a screwdriver and push it in that prong and try to straighten an outlet that is twisted. It could of course just have been damaged anywhere from when factory made it to untill the time it was installed


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RE: odd problem at school

as for the melting of the plug should i be afraid of it catching fire or burning someones hand when they go to unplug the tools? if so would you recommend to replace the outlets again?


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RE: odd problem at school

absolutely. If this truly is the problem (which it seems very likely) the more likely situation to occur is that the arcing from the loose connection will heat up to the point where it will cause a fire. I would reccoment to at least replace the outlet in question. We are talking about one outlet that is doing this, correct?


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RE: odd problem at school

nooooo this is just about every outlet in the school. my laptop cord actually had to be replaced because of this issue also. im not sure exactly what this issue is and i just got a voicemail that 5-7 computers have melted plugs also and this is worring me alot now.


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RE: odd problem at school

Since "...they just replaced all the outlets in the room last school year..." It appears that "they" may have used an inferior brand/type of outlet.


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RE: odd problem at school

the inferior brand/type of outlet would not surprise me because of all the budget cuts.


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RE: odd problem .... now multiple tools

We've seen that before....with multiple fault points you need a common cause......you probably need to be looking for a bad panel Connection.......probably a "bad" Neutral

Meter the voltage and check.....


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RE: odd problem at school

thanks a lot i will monitor the voltage and check all the connections in the panels and get back to you


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RE: odd problem at school

all the connections and voltages check out in all outlets so im confused i also replaced 3 outlets today plugged in new tool and same burnt prong and melting plug.


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RE: odd problem at school

bus and petey have it right. the prong is getting hot because of a high resistance "bad" connection at the receptacle. replace one of the bad receptacles with a high quality one from supplier, not from those on hand. then plug in an appliance thats plug has not been compromised. you will not have a problem at the newly replaced receptacle. Then you will have many others to replace.


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RE: odd problem at school

replaced 3 outlets with leviton industrial grade ones plugged in a new tool a drill in this case and within 5 minutes or so same blackening happened. im thinking this may be something with the POCO.


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RE: odd problem at school

Sorry if I'm being cynical, but does anybody else have the word "troll" come to mind...? When I was in school, I was never allowed to replace outlets and check all the connections in the panels... Give me a break!


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RE: odd problem at school

You don't need an electrician you need a Priest, as this is not an elecrical problem it is a poltergeist. A Bible a Cross and a bottle of Holy water and you are set. If you do call the power company and ask why they are suppling you with defective power, please record the call so you can post verbatim their answer.


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RE: odd problem at school

The OP has not indicated that he is a student, and certainly could be in a position where he would be allowed to replace outlets. However it does seem that his problem defies explaination somehow. How about let's blame it on Chinese drywall and move on.


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RE: odd problem at school

Sorry if I'm being cynical, but does anybody else have the word "troll" come to mind...? When I was in school, I was never allowed to replace outlets and check all the connections in the panels... Give me a break!

heh... I was in a position, as a high school student, where I was permitted to do this - as well as replacing light ballasts and occasional tinkering with the wiring to the 1940s boilers...

Of course, I also had the principal making "wooden washers" with a tablesaw during the installation of an intercom system... it was definitely an unusual school.


All that aside, this thread is BS. The OP has made up a scenario which is not scientifically possible. I vote we track his IP address and semipermanently install his face in a concrete wall.


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RE: odd problem at school

this may not be scientifically possible but it is indeed happening. and even the POCO cant figure out why.


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RE: odd problem at school

They're here.


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RE: odd problem at school

matt
im calling you out on this one. we need to see pictures of this anomaly.

twenty seven eight-by-ten color glossy photographs with circles and arrows and a paragraph on the back of each one explaining what each one was. we need pictures of the approach, the getaway, the northwest corner the southwest corner and that's not to mention the aerial photography.

please post these on the web somewhere and provide us with a link.


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RE: odd problem at school

I suspect Matt is telling the truth.......

Here's a wiki "three-phase" excerpt:

""If the supply neutral of a three-phase system with line-to-neutral connected loads is broken, the voltage balance on the loads will no longer be maintained. The neutral point will tend to drift toward the most heavily loaded phase, causing undervoltage conditions on that phase only. Correspondingly, the lightly-loaded phases may approach the line-to-line voltage, which exceeds the line-to-neutral voltage by a factor of √3, causing overheating and failure of many types of loads.""

After the 2004 Hurricanes in Florida I saw all kinds of weird single-phase problems associated with poor/broken Neutral connections.....Many of the strain reliefs (or connections) broke AND they were used as part of the Neutral conductor........

Disclaimer: I'm NOT an Electrician....just a handy guy


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RE: odd problem at school

abnorm
the loose neutral problem may destroy 120v equipment as it will tend to increase and decrease voltage on the lines in proportion to the loads applied to them. this situation does not cause the problem described by matt. this problem is caused by heat developed at a bad connection. if matt is telling the truth, let him post the pictures. I can't wait to see the evidence.


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RE: odd problem at school

i will post pictures as soon as i can. thanks again, matt


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RE: odd problem at school

You wouldn't think that in a school setting it would be that hard to get some photos published to the web. photobucket is ready when you are matt.


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RE: very odd problem at school

Could it have escalated to the point they had to close the school and evacuate the building?


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RE: odd problem at school

"... I just saw on the news that an entire town has now been occupied by left blade, from ground, aliens have occupied an entire town. Unfortunately, digital pictures of this event have been unavailable since they are now entering the digital cameras themselves. Please stand-by for updates...


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RE: odd problem at school

C'mon... People like Matt look really good with their faces smashed in!


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RE: odd problem at school

Where are the pictures matt? Did it burn up all the computers and your camera charger too?
Wait I think I smell something burning. Ooh noooo it has gone viral. Quick; everyone unplug everything before its too late!


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RE: odd problem at school

the pictures will be up by wednesday.


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RE: odd problem at school

It's gonna take about that long to walk around the school with a torch...


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RE: odd problem at school

give me about thirty minutes with photo shop and I could have more photos than viagra has blue pills.


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RE: odd problem at school

Blue pills are out, too expensive. New HC plan is popsickle stick and duct tape.


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RE: odd problem at school

just FYI our district was off this week so i couldnt get pictures. thats why theyll be up by wednesday


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RE: odd problem at school

did anybody really expect to see any pictures? there again he didn't say which wednesday they would be up by.


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RE: odd problem at school

sorry for digging out this old thread, but i want to know what was wrong.


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RE: odd problem at school

Golly by gosh smithy, I was very much wondering something when all of the sudden you should bring this up...


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RE: odd problem at school

Hey Smithy.. ask Matt where the pictures are tomorrow.


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