Cornrr taped and center taped deltas.

[dfloodhvac]

Sooo I'm an hvac technician with a through understanding of electricity. And today i ran across a Y to delta step up transformer installation with a corner taped grounded delta secondary side... this was a Y 208va primary delta step up 240 va secondary.... funny thing was whoever installed this step up corner grounded delta tried to bond a neutral with the corner taped ground in an attempt to pull 120 va circuits. Now i know a corner taped delta can't be neutraled for 120 power because the corner ground is at phase voltage. But can i pull a neautral bus from the supply 208 Y transformer in order to pull 120 power. And is this code??

 

[Knobhead]

There’s several things of concern:

• Very few UK electricians, unlike me, understand corner and centre grounded ∆.
• “I'm an hvac technician with a through understanding of electricity” so as you’re not an electrician to would be remiss to advise you.
• Very few UK electricians, again unlike me, have a copy of the NEC code.

I’ll give you a hint, look at section 250 in the NEC code book.

 

[dfloodhvac]

Alright god.... it just erks me wen electricians think they're holier than thou. Unfortunately you dnt kno wat ur talking about. I dnt need theory.

 

[UNG]

Sooo I'm an hvac technician with a through understanding of electricity. And today i ran across a Y to delta step up transformer installation with a corner taped grounded delta secondary side... this was a Y 208va primary delta step up 240 va secondary.... funny thing was whoever installed this step up corner grounded delta tried to bond a neutral with the corner taped ground in an attempt to pull 120 va circuits. Now i know a corner taped delta can't be neutraled for 120 power because the corner ground is at phase voltage. But can i pull a neautral bus from the supply 208 Y transformer in order to pull 120 power. And is this code??

So why are you asking the question

Alright god.... it just erks me wen electricians think they're holier than thou. Unfortunately you dnt kno wat ur talking about. I dnt need theory.

it just erks me wen hvac technicians think they're holier than thou.

No actually it really pi$$e$ me off when dicks like you take an attitude because the answer you want isn't forthcoming. Would you care to tell me the best way to regas my aircon probably not but hey wow poo happens

 

[dfloodhvac]

The funny thing is real hvac techs can easily transition to electrical work...... i know what problem and its alrdy been fixed to code i electricians are dumber than a box of rocks light bulb changers.... get a life better yet get a technical trade tht actually requires analytical skill...

 

[trev]

Yet another one who throws his toys out of the pram because he didn't get the answer he wanted.
Tell me, since it's acceptable for us to advise an hvac person where does the line get drawn for it to be acceptable not to advise someone?
Joiner?
Plumber?
Police officer?
Art teacher?
Nurse?
Just so as I know for later, since I'm as dumb as a box of rocks.
Idiot.

 

[Besoeker]

Sooo I'm an hvac technician with a through understanding of electricity. And today i ran across a Y to delta step up transformer installation with a corner taped grounded delta secondary side... this was a Y 208va primary delta step up 240 va secondary.... funny thing was whoever installed this step up corner grounded delta tried to bond a neutral with the corner taped ground in an attempt to pull 120 va circuits. Now i know a corner taped delta can't be neutraled for 120 power because the corner ground is at phase voltage. But can i pull a neautral bus from the supply 208 Y transformer in order to pull 120 power. And is this code??

Corner grounded delta is relatively common in USA. The centre (center) tapped winding is is sometimes called a high leg or a wild leg.

It sounds like you have an American design and that will be rated for 60Hz. If you intend to use it here, UK, that might be a problem. Things like motors and transformers may well saturate owing to the higher V/f ratio - 240/50 instead of 240/60.
There is no simple way round that.

If you want help with NEC code you might try here:

http://forums.mikeholt.com/index.php

in the NEC section.
There are people there who will be very helpful.

Like many forums, your first several posts will be monitored before they get posted.
And, FYI, profanities of any sort are not permitted.

To the admin here - I am a member there but I am not trying to poach membership.....

 

[dfloodhvac]

Thr line gets drawn as far as ur knowledge is capable of reaching which seems to a a general basic knowledge of nothing pertient nor applicably. Why don't u electricians all get together and discuss the line of professionalism you seem to lack... there's a reason why the industry is full of innept bulb changers...

 

[UNG]

Thr line gets drawn as far as ur knowledge is capable of reaching which seems to a a general basic knowledge of nothing pertient nor applicably. Why don't u electricians all get together and discuss the line of professionalism you seem to lack... there's a reason why the industry is full of innept bulb changers...

Your right it does report sent to mods

Typical HVAC tech full of hot air and $$$$

 

[Besoeker]

Yet another one who throws his toys out of the pram because he didn't get the answer he wanted.
Tell me, since it's acceptable for us to advise an hvac person where does the line get drawn for it to be acceptable not to advise someone?
Joiner?
Plumber?
Police officer?
Art teacher?
Nurse?
Just so as I know for later, since I'm as dumb as a box of rocks.
Idiot.

A tad harsh I thought.

 

[UNG]

A tad harsh I thought.

I thought it was quite restrained

 

[Lucien Nunes]

As besoeker says this configuration is widely used in the US but scarcely at all in the UK, so posting about it on a UK-based forum is probably not going to get you a lot of good answers. The theory is the same the world over but the practice, for historical reasons, is quite different. In other words, the fact that Tony knows about this kind of hookup at all is testament to his wide-ranging knowledge and experience. I would hesitate to call him a bulb-changer although I suspect he could make quite a good job of that too

 

[dfloodhvac]

Btw electrician... corner grounded deltas don't have a wild leg.... tht would be a center taped delta..... to whoever posted earlier

 

[dfloodhvac]

Incompetence.....

 

[Knobhead]

Corner grounded delta is relatively common in USA. The centre (center) tapped winding is is sometimes called a high leg or a wild leg.

It sounds like you have an American design and that will be rated for 60Hz. If you intend to use it here, UK, that might be a problem. Things like motors and transformers may well saturate owing to the higher V/f ratio - 240/50 instead of 240/60.
There is no simple way round that.

If you want help with NEC code you might try here:

Mike Holt's Forum

in the NEC section.
There are people there who will be very helpful.

Like many forums, your first several posts will be monitored before they get posted.
And, FYI, profanities of any sort are not permitted.

To the admin here - I am a member there but I am not trying to poach membership.....

So am I, I'll give him a warm welcome there as well. Not that I think he would last long.
I'm also on CR4.

 

[Lucien Nunes]

Incompetence.....

Just remember we don't use any of these systems over here! We don't have centre-tapped delta, wild legs or any such thing, so an electrician isn't incompetent not to know about them, just unfamiliar with overseas practice. Are you familiar with the crossed-ends test procedure for a ring-final?

 

[Darkwood]

Thr line gets drawn as far as ur knowledge is capable of reaching which seems to a a general basic knowledge of nothing pertient nor applicably. Why don't u electricians all get together and discuss the line of professionalism you seem to lack... there's a reason why the industry is full of innept bulb changers...

Your attitude stinks ...you are correct the industry is full of inept bulb changers it has been for yrs but Tony the guy you attacked is not one of them and is a very knowledgeable guy who has a lot to offer the forum and he'd be the first one on here I'd recommend having a chat to if you have Tx or Motor issues as he's spanned most his life in that field....

He directed you the section to look up in the NEC code, these are not cheap to purchase so why should he reel off the regulations for free.... I suggest you pick the toys up you threw out of the pram and try starting again .... coming on the forum and slagging off members will see you banned you came for help here so don't throw it back in our faces when you are given it, just because it means you will have to do some searching yourself and its not as direct answer as you wanted is no reason to attack members of the forum ....

Hope you get this post before your banned ...rant over:veryangry2:

 

[Besoeker]

In other words, the fact that Tony knows about this kind of hookup at all is testament to his wide-ranging knowledge and experience. I would hesitate to call him a bulb-changer although I suspect he could make quite a good job of that too

I don't think the OP called him a bulb changer.

 

[Besoeker]

Btw electrician... corner grounded deltas don't have a wild leg.... tht would be a center taped delta..... to whoever posted earlier

It was me.
You are quite correct.
You didn't mention a centre tapped winding.
But some installations do.

Anyway, take heed of my point about the different frequencies.

 

[UNG]

I don't think the OP called him a bulb changer.

He called all electricians bulb changers

I think he is a bored HVAC tech that is recovering at home because of the injuries sustained on site