magger 5kv Qu?

[saudi_lineman]

hi guyz...!

i wanna magger transformer 15 kva by magger 5kv.but ihave problomes with the rusalt i dont know the accpt rusalt .would you plase help me wht is the coorect resault ?

H1*Ground = ??
H2*G=??
H1*H2= ??

H1*X1=??
H1*X2=??
H1*X3=??

H2*X1=??
H2*X2=??
H2*X3=??

X1*X2=??
X1*X3=??
X2*X3=??

X1*G=??
X2*G=??
X3*G=??

^
:
:
is it corrct mathod ?

Nots:
transformer connection is serice A - BC -D .
HV 13.8kv

[bren guzzi]

SERIOUSLY DUDE..... NO DISRESPECT. If you've gotta come on this forum to find that out........ Then there's something Wrong..... I'm not gona tell ya "although I know how to megga a transformer....... Because YOU SHOULDN'T BE DOING IT if ya gotta ask that . SORRY MAN.. : (

[topgroove]

SERIOUSLY DUDE..... NO DISRESPECT. If you've gotta come on this forum to find that out........ Then there's something Wrong..... I'm not gona tell ya "although I know how to megga a transformer....... Because YOU SHOULDN'T BE DOING IT if ya gotta ask that . SORRY MAN.. : ( Bren, we kinda cut this kid a little slack around here. He's a young Saudi kid trying to learn, sort of like an apprentice. The kid is actually very inteligent, but lacks someone to learn from.


Now saudi-lineman.... When you say "magga" , do you mean megger?



With two conductors that are supposed to be insulated, the amount of insulation can vary depending on the thickness of the insulating material, the amount of moisture, or from being contaminated with an electrically conductive substance. The insulation could be thin in one or more spots due to improper manufacture, or due to overheating, or due to applying excessive mechanical force, etc. So, megging the insulation is intended to check for any of these imperfections.

When the voltage is applied across two conductors that are supposed to be insulated, the megohmmeter measures the current that flows. If the current is lesss than the specified amount, then the insulation is meeting the specified minimum. If it fails the test, then there is a problem such as I mentioned above.

Or do you mean measure the voltage across the bushings? The primary coil H1 and H2

and the secondary coil X1, X2, and x3.

Once we figure out your question we can get into a transformer theory discussion.

[bren guzzi]

Sorry topgrove.... But with the utmost respect..... He shoudnt have to come on here with a Q like that......... Where's his training over there... ??????????? I'm still angry after writing about the 2 guys killed in oklahoma........ I learned how to megger transformers 30 years ago in a trainig school.... And again several times before I was expected to do it for real... I never forgot how and have taught hundreds of guys since...... Person to person. There's a right way to learn an in my humble oppinion..... It aint here.... But good luck with it. I honestly don't mean to be disrespectful to you or him....... :(

[topgroove]

No disrespect taken, I hear what you're saying. I'm Irish too Bren
:)
The training these kids in Saudi get leaves alot to be desired. Seams there are two clases of people over there . the rich elite and the working people. The rich could care less how many of the unwashed mases get killed as long as their power dosen't go out.


I kinda found a soft spot for saudi lineman. the kid seams really eager to learn and is actually quite intelligent. When he first came here to the forum I kinda ragged on him and posted some off the cuff remarks. But the kid took it on the chin like a champ.

[Lineman North Florida]

How come at the bottom of his post is a perfectly spelled sentence and nothing close to being spelled correctly in his whole post, I figured it was probably someone with multiple screen names trying to get a laugh, maybe not.

[bren guzzi]

I went out to saudi in the 80,s to train some teams up forr a specific job for the ESB. It was a real eye opener.......... Hardest and most rewarding job I ever did. Funny too at times. I'm a bit upset about the two guys dying in the accident forum " maybe we should start an obitury forum... And just add each name to it as they die....... How long would it have to get before action is taken ???????? We've all these memorials to the fallen militery. An rightly so. But I'd love one in the center of Washinton with a full time engraver adding the next lineman to get killed. Maybe someone would take notice then. ??????? Any way sorry dude ! You help the guy out ... An all the best SAUDI DUDE.... :)

[topgroove]

How come at the bottom of his post is a perfectly spelled sentence and nothing close to being spelled correctly in his whole post, I figured it was probably someone with multiple screen names trying to get a laugh, maybe not.

I think that sentence at the bottom is a copy&paste quote that he found profound.
I try not to pick on his spelling, Quite frankly, I'm ashamed of mine.


Does not diminish the value of what one might be better than you in the eyes of others

Wow... kinda deep! Kinda like saying... Don't be so quick judge others because in the big picture you may also be judged !

[saudi_lineman]

Bren, we kinda cut this kid a little slack around here. He's a young Saudi kid trying to learn, sort of like an apprentice. The kid is actually very inteligent, but lacks someone to learn from.


Now saudi-lineman.... When you say "magga" , do you mean megger?



With two conductors that are supposed to be insulated, the amount of insulation can vary depending on the thickness of the insulating material, the amount of moisture, or from being contaminated with an electrically conductive substance. The insulation could be thin in one or more spots due to improper manufacture, or due to overheating, or due to applying excessive mechanical force, etc. So, megging the insulation is intended to check for any of these imperfections.

When the voltage is applied across two conductors that are supposed to be insulated, the megohmmeter measures the current that flows. If the current is lesss than the specified amount, then the insulation is meeting the specified minimum. If it fails the test, then there is a problem such as I mentioned above.

Or do you mean measure the voltage across the bushings? The primary coil H1 and H2

and the secondary coil X1, X2, and x3.

Once we figure out your question we can get into a transformer theory discussion.






Thank topgroove for your cooperation

Well, will re-wording of the question I have a new transformer and I want to test it
Is the method the above are correct?
And What are acceptable results after testing transformer?

[saudi_lineman]

My way to test transformer by Manual magger i know if the winding sort it will get zero , if not it will be Infinite but the digital megger i don't know what is the correct result

[topgroove]

I'll help you out. I'm off today, but if I get a chance i'll take some ohm readings on a transformer tomorrow in the yard.


In basic transformer theory. you have a primary coil ( H1 and H2) and a secondary coil (A BC D) or X3 X2 X1 bushings both coils of wire are wound around a common ferrite core. The primary coil is thousand of turns of thin insulated wire. The secondary coil has much fewer turns of much larger guage wire. With a 120/240 volt secondary Think of your secondary coil as one coil of wire with A the start of the coil and D the end of the coil . BC is the midpoint tap of that coil. the X2 bushing. There is no electrical connection between the primary coil and secondary coil. When an alternating current voltage is applied to the primary coil . A sine wave,,, that in this country is 60 times a second or 60 hertz an induced voltage will appear on the secondary coil. the secondary voltage will depend on the turns ratio. The turns ratio is the number of turns on the primary coil compared to the secondary coil.

NOW... VERY IMPORTANT... I AM ASUMING THE TRANSFORMER IS DE-ENERGIZED! NOTHING IS HOOKED UP TO IT, AND ITS SITTING ON THE SHOP FLOOR!

When you take a fluke multimeter and set it to olms you can measure the resistance of the primary coil and the secondary coil. Sounds like you have a 5KV meggaolmmeter in your shop. A usefull tool, but I'ld stick to a plain old fluke multimeter.


You can measure the resistance between H1 and H2 . and the resistance between X1 and X3.... X3 and X2 and X1 and X2


I'm not sure why you would ever measure between the primary coil and the secondary coil?? Like I said there is no electrical connection between the primary and secondary unless the transformer is a single bushing type and the X2 groundstrap is connected.

Which leads me to ask is your distribution primary a wye or a delta? does it cycle at 60 Hertz?

[saudi_lineman]

ah nice

that mean magger for insolation bttwen the turn
and fluke multimeter for resistance

that mean the test will be like this

by magger:
1-x1*x2 .. x1.x3 x2.x3

1-h1*h2

by mult:

btween HV , LV and ground


our primary is delta all our overhed are delta

[topgroove]

ah nice

that mean magger for insolation bttwen the turn
and fluke multimeter for resistance

that mean the test will be like this

by magger:
1-x1*x2 .. x1.x3 x2.x3

1-h1*h2

by mult:

btween HV , LV and ground


our primary is delta all our overhed are delta

Exactly... Delta Primarys are my favorite. I'll take some readings tommorow for you. Our Delta primary is is only 4.8 KV so our readings won't match, I'll take some olm reading on a 7.6 KV wye also for comparison. Now get to sleep.... Its got to be the middle of the night over there:)

[Lineman North Florida]

I think that sentence at the bottom is a copy&paste quote that he found profound.
I try not to pick on his spelling, Quite frankly, I'm ashamed of mine.


Does not diminish the value of what one might be better than you in the eyes of others

Wow... kinda deep! Kinda like saying... Don't be so quick judge others because in the big picture you may also be judged !
I wasn't really picking on his spelling, I was simply stating that I figured it could be one of the many alter egos that are on this site who were fishing to see where it would go, I try not to judge either, true colors on here are quite evident.

[topgroove]

I wasn't really picking on his spelling, I was simply stating that I figured it could be one of the many alter egos that are on this site who were fishing to see where it would go, I try not to judge either, true colors on here are quite evident.

I hear you ... In fact, I thought the same thing awhile back... I'm from NY so you can imagine how skeptical I am of Saudi's. I remember awile back when he first posted I really rode the guy hard and posted some inappropiate remarks to test him out... The kid took it on the chin like a champ. I'm convinced he's a fine young man thats eager and has a drive to learn.

[rcdallas]

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[topgroove]

I have this little transformer tester that works pretty nice. It's simple operation, two leads. You check all your secondary bushings, X1-X3, X1-X2, X3-X2 - H1-X1, etc.

(everything isolated)

It either gives you a green light or red light. I suppose if a single service was hooked directly to it and with the cutout opened up you could use it from a meter socket.

Beats closing in on a fuse. I've tried with a fluke doing some of this but after getting some jacked up readings I just elect to the previous. Though after reading this I suppose with different voltages and everything you'd get different readings.

Not to long ago I was out with Transmission watching them test a substation power transformer and they use what I think is called a TTR machine (transformer turn ratio); where from what I was told they were pumping in 10kv and had a computer hooked up doing some extensive tests to it. Don't know much about it but that's what they were using.

I'm a cockroach and nab onto whatever tools / test equipment people don't want to carry on their truck.Hey RC whats the name of the transformer tester, I'ld love to get one one my truck. Your right... it sure beats closing the cutout.

[rcdallas]

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[Pootnaigle]

Ummmmmmmmmmm Groovester they also make one thats tests both transformers and cowpastures n it werks good.

[topgroove]

Whats a cowpastur

[Pootnaigle]

Ummmmmmm COWPASTURE= Capacitor

[reppy007]

Ummmmmmm COWPASTURE= Capacitor

Just when i thought i was lost,about the subject,now i know i was lost with that cowpasture quote.Poot,no offense but are you a real hillbilly?Seems that way,if so your the coolest hillbilly in america.:tired:

[lewy]

Hey RC whats the name of the transformer tester, I'ld love to get one one my truck. Your right... it sure beats closing the cutout.

Hastings makes 1 as well, a nice little unit.