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#1 User is offline   rcdallas 

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Posted 06 February 2010 - 10:36 AM

Ok you got yourself a CSP 120/240 transformer...

Lets say you wanted straight 240, so you move your ground strap to over to x3...

With the breaker closed, you check voltage, x3 to x2, you get 120, x3 to x1 you get 240.

If you open the breaker on this this CSP and check voltage... what do you think your gonna get?

I'll give you a hint, don't do this on a CSP.


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#2 User is online   olo131 

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Posted 06 February 2010 - 10:52 AM

Come on Power guys this should be easy for you. Don't let a Cable Guy be right.

I guess....... you move the oscillating knibbling pin to the third phase shifting connector......

Just having fun... I would love to see some real guesses.

Thanks for the post
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#3 User is offline   wood stabber 

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Posted 06 February 2010 - 05:58 PM

QUOTE (rcdallas @ Feb 6 2010, 10:36 AM) <{POST_SNAPBACK}>
Ok you got yourself a CSP 120/240 transformer...

Lets say you wanted straight 240, so you move your ground strap to over to x3...

With the breaker closed, you check voltage, x3 to x2, you get 120, x3 to x1 you get 240.

If you open the breaker on this this CSP and check voltage... what do you think your gonna get?

I'll give you a hint, don't do this on a CSP.


Why did you ground X3?That causes a phase to ground.... If I wanted 240v I would've used X1 and X3 and left X2 alone...
And lastly...if you OPEN the pot ,how you gonna check voltage? I guess if you had backfeed you get a reading on you volt meter,but that's not telling you if your pots good or not!
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#4 User is offline   rcdallas 

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Posted 06 February 2010 - 08:35 PM

QUOTE (wood stabber @ Feb 6 2010, 06:58 PM) <{POST_SNAPBACK}>
QUOTE (rcdallas @ Feb 6 2010, 10:36 AM) <{POST_SNAPBACK}>
Ok you got yourself a CSP 120/240 transformer...

Lets say you wanted straight 240, so you move your ground strap to over to x3...

With the breaker closed, you check voltage, x3 to x2, you get 120, x3 to x1 you get 240.

If you open the breaker on this this CSP and check voltage... what do you think your gonna get?

I'll give you a hint, don't do this on a CSP.


Why did you ground X3?That causes a phase to ground.... If I wanted 240v I would've used X1 and X3 and left X2 alone...
And lastly...if you OPEN the pot ,how you gonna check voltage? I guess if you had backfeed you get a reading on you volt meter,but that's not telling you if your pots good or not!


You ground the X3 or X1 so that you get straight 240... it'll give you a 240 hot leg to ground... we use that configuration on our street light circuits...

If you open the breaker on a CSP in this type of configuration you'll end up with primary voltage due to the physical design of the CSP loosing a reference to ground with the ground strap not being on the X2 bushing.


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#5 User is offline   wood stabber 

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Posted 07 February 2010 - 08:29 AM

QUOTE (rcdallas @ Feb 6 2010, 08:35 PM) <{POST_SNAPBACK}>
QUOTE (wood stabber @ Feb 6 2010, 06:58 PM) <{POST_SNAPBACK}>
QUOTE (rcdallas @ Feb 6 2010, 10:36 AM) <{POST_SNAPBACK}>
Ok you got yourself a CSP 120/240 transformer...

Lets say you wanted straight 240, so you move your ground strap to over to x3...

With the breaker closed, you check voltage, x3 to x2, you get 120, x3 to x1 you get 240.

If you open the breaker on this this CSP and check voltage... what do you think your gonna get?

I'll give you a hint, don't do this on a CSP.


Why did you ground X3?That causes a phase to ground.... If I wanted 240v I would've used X1 and X3 and left X2 alone...
And lastly...if you OPEN the pot ,how you gonna check voltage? I guess if you had backfeed you get a reading on you volt meter,but that's not telling you if your pots good or not!


You ground the X3 or X1 so that you get straight 240... it'll give you a 240 hot leg to ground... we use that configuration on our street light circuits...

If you open the breaker on a CSP in this type of configuration you'll end up with primary voltage due to the physical design of the CSP loosing a reference to ground with the ground strap not being on the X2 bushing.


Thanks,that's nice to know,you don't see to many CSP's out here in Cali,they have been changing them out to conventionals for a long time, pull the doors,drop the pot,hang a new pot,plug it in.
So when you say you will get primary voltage,are you meaning the secondary side will read primary voltage ?
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#6 User is offline   strange052 

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Posted 07 February 2010 - 04:08 PM

QUOTE (rcdallas @ Feb 6 2010, 11:36 AM) <{POST_SNAPBACK}>
Ok you got yourself a CSP 120/240 transformer...

Lets say you wanted straight 240, so you move your ground strap to over to x3...

With the breaker closed, you check voltage, x3 to x2, you get 120, x3 to x1 you get 240.

If you open the breaker on this this CSP and check voltage... what do you think your gonna get?

I'll give you a hint, don't do this on a CSP.



I call over to the local POWER yard and offer to buy one of them a case of beer for hoooking it up for me, because Im just a phone guy that dont know sh*t about power
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#7 User is offline   System Tech Senior 

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Posted 07 February 2010 - 04:14 PM

LOL@ Strange
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#8 User is online   olo131 

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Posted 07 February 2010 - 04:16 PM

Well Strange you could have still given a guess you know as much as I do when it comes to Power and I gave it a go!!!!

Hell LRod didn't even guess and he said he reads every post....... Maybe he will need to hit the books...... devil-smiley-024[1].gif

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#9 User is offline   System Tech Senior 

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Posted 07 February 2010 - 04:23 PM

I'm gonna go with nothing since it's open. :)
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#10 User is offline   Lightningrod 

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Posted 07 February 2010 - 04:52 PM

QUOTE (wood stabber @ Feb 6 2010, 05:58 PM) <{POST_SNAPBACK}>
QUOTE (rcdallas @ Feb 6 2010, 10:36 AM) <{POST_SNAPBACK}>
Ok you got yourself a CSP 120/240 transformer...

Lets say you wanted straight 240, so you move your ground strap to over to x3...

With the breaker closed, you check voltage, x3 to x2, you get 120, x3 to x1 you get 240.

If you open the breaker on this this CSP and check voltage... what do you think your gonna get?

I'll give you a hint, don't do this on a CSP.


Why did you ground X3?That causes a phase to ground.... If I wanted 240v I would've used X1 and X3 and left X2 alone...
And lastly...if you OPEN the pot ,how you gonna check voltage? I guess if you had backfeed you get a reading on you volt meter,but that's not telling you if your pots good or not!


I can see the 240V no problem, you have hot on one end and ground on the other end of you windings as you do with primary as the x3 acts the same as your h2.
Do you know why you get line voltage on the secondary winding, we have alot of 240V streelight circuits on the housing areas of the local military base. I don't know if any CSP's are feeding it though but we still have a few thousand CSP's in our system.
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#11 User is online   olo131 

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Posted 07 February 2010 - 05:02 PM

QUOTE (olo131 @ Feb 7 2010, 06:16 PM) <{POST_SNAPBACK}>
Hell LRod didn't even guess and he said he reads every post....... Maybe he will need to hit the books...... devil-smiley-024[1].gif

olo131

QUOTE (Lightningrod @ Feb 7 2010, 06:52 PM) <{POST_SNAPBACK}>
I can see the 240V no problem, you have hot on one end and ground on the other end of you windings as you do with primary as the x3 acts the same as your h2.
Do you know why you get line voltage on the secondary winding, we have alot of 240V streelight circuits on the housing areas of the local military base. I don't know if any CSP's are feeding it though but we still have a few thousand CSP's in our system.



Looks like peer pressure to me!!!!!! devil-smiley-024[1].gif

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#12 User is offline   System Tech Senior 

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Posted 07 February 2010 - 05:06 PM

Do we have an answer yet lol?? I'm kinda curious to know lol.
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#13 User is offline   rcdallas 

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Posted 07 February 2010 - 09:37 PM

QUOTE (wood stabber @ Feb 7 2010, 08:29 AM) <{POST_SNAPBACK}>
QUOTE (rcdallas @ Feb 6 2010, 08:35 PM) <{POST_SNAPBACK}>
QUOTE (wood stabber @ Feb 6 2010, 06:58 PM) <{POST_SNAPBACK}>
QUOTE (rcdallas @ Feb 6 2010, 10:36 AM) <{POST_SNAPBACK}>
Ok you got yourself a CSP 120/240 transformer...

Lets say you wanted straight 240, so you move your ground strap to over to x3...

With the breaker closed, you check voltage, x3 to x2, you get 120, x3 to x1 you get 240.

If you open the breaker on this this CSP and check voltage... what do you think your gonna get?

I'll give you a hint, don't do this on a CSP.


Why did you ground X3?That causes a phase to ground.... If I wanted 240v I would've used X1 and X3 and left X2 alone...
And lastly...if you OPEN the pot ,how you gonna check voltage? I guess if you had backfeed you get a reading on you volt meter,but that's not telling you if your pots good or not!


You ground the X3 or X1 so that you get straight 240... it'll give you a 240 hot leg to ground... we use that configuration on our street light circuits...

If you open the breaker on a CSP in this type of configuration you'll end up with primary voltage due to the physical design of the CSP loosing a reference to ground with the ground strap not being on the X2 bushing.


Thanks,that's nice to know,you don't see to many CSP's out here in Cali,they have been changing them out to conventionals for a long time, pull the doors,drop the pot,hang a new pot,plug it in.
So when you say you will get primary voltage,are you meaning the secondary side will read primary voltage ?



Yes... you'll end up with primary voltage out the secondary bushings in that configuration. We don't have many CSP's out here anymore on our system, but you'll come across them every now and then.



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#14 User is offline   rcdallas 

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Posted 07 February 2010 - 09:46 PM

QUOTE (Lightningrod @ Feb 7 2010, 04:52 PM) <{POST_SNAPBACK}>
QUOTE (wood stabber @ Feb 6 2010, 05:58 PM) <{POST_SNAPBACK}>
QUOTE (rcdallas @ Feb 6 2010, 10:36 AM) <{POST_SNAPBACK}>
Ok you got yourself a CSP 120/240 transformer...

Lets say you wanted straight 240, so you move your ground strap to over to x3...

With the breaker closed, you check voltage, x3 to x2, you get 120, x3 to x1 you get 240.

If you open the breaker on this this CSP and check voltage... what do you think your gonna get?

I'll give you a hint, don't do this on a CSP.


Why did you ground X3?That causes a phase to ground.... If I wanted 240v I would've used X1 and X3 and left X2 alone...
And lastly...if you OPEN the pot ,how you gonna check voltage? I guess if you had backfeed you get a reading on you volt meter,but that's not telling you if your pots good or not!


I can see the 240V no problem, you have hot on one end and ground on the other end of you windings as you do with primary as the x3 acts the same as your h2.
Do you know why you get line voltage on the secondary winding, we have alot of 240V streelight circuits on the housing areas of the local military base. I don't know if any CSP's are feeding it though but we still have a few thousand CSP's in our system.



I posted it previously... it's just the physical design of the CSP, when you open the breaker it breaks physical contact between X3 and X1 and X2 stays closed.

We will use the straight 240, and where a photocell/relay is needed for 120 we'll use the 120v to power it, at one time someone was shootin some trouble checking voltage it burned their volt meter up... later on they used phasing sticks and seen there was primary voltage.. thankfully noone hurt.

Some shiznit to think about it.
E * I = P
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#15 User is offline   topgroove 

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Posted 08 February 2010 - 06:37 AM

QUOTE (rcdallas @ Feb 8 2010, 12:46 AM) <{POST_SNAPBACK}>
QUOTE (Lightningrod @ Feb 7 2010, 04:52 PM) <{POST_SNAPBACK}>
QUOTE (wood stabber @ Feb 6 2010, 05:58 PM) <{POST_SNAPBACK}>
QUOTE (rcdallas @ Feb 6 2010, 10:36 AM) <{POST_SNAPBACK}>
Ok you got yourself a CSP 120/240 transformer...

Lets say you wanted straight 240, so you move your ground strap to over to x3...

With the breaker closed, you check voltage, x3 to x2, you get 120, x3 to x1 you get 240.

If you open the breaker on this this CSP and check voltage... what do you think your gonna get?

I'll give you a hint, don't do this on a CSP.


Why did you ground X3?That causes a phase to ground.... If I wanted 240v I would've used X1 and X3 and left X2 alone...
And lastly...if you OPEN the pot ,how you gonna check voltage? I guess if you had backfeed you get a reading on you volt meter,but that's not telling you if your pots good or not!


I can see the 240V no problem, you have hot on one end and ground on the other end of you windings as you do with primary as the x3 acts the same as your h2.
Do you know why you get line voltage on the secondary winding, we have alot of 240V streelight circuits on the housing areas of the local military base. I don't know if any CSP's are feeding it though but we still have a few thousand CSP's in our system.



I posted it previously... it's just the physical design of the CSP, when you open the breaker it breaks physical contact between X3 and X1 and X2 stays closed.

We will use the straight 240, and where a photocell/relay is needed for 120 we'll use the 120v to power it, at one time someone was shootin some trouble checking voltage it burned their volt meter up... later on they used phasing sticks and seen there was primary voltage.. thankfully noone hurt.

Some shiznit to think about it.

True... because of the design of a CSP opening the breaker on a CSP does does de-energize the secondary coil but an induced voltage will develop on the coil. It can reach the potential of the primary coil we're talking mili amps though. When using a fluke multimeter you can destroy it(and I have ) by testing across the bushings with the secondary breaker in the open position. Always better to use an ellwood.
To clear thing up on grounding a secondary coil.... A secondary coil can take ONE ground. The transformer could care less if its x1, x2, or x3. When building a straight 240 bank the ground straps are omited. We ground one of the hotlegs in this case. Your phase to phase voltage on any two hotlegs will be 240 but your voltage from the grounded hotleg to ground will of cource be zero.
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#16 User is offline   topgroove 

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Posted 08 February 2010 - 10:49 AM

QUOTE (System Tech Senior @ Feb 7 2010, 08:06 PM) <{POST_SNAPBACK}>
Do we have an answer yet lol?? I'm kinda curious to know lol.
I just answered it two posts ago in this thread.When you open the breaker on a csp an induced voltage will develop on the secondary coil. the voltage can reach the potential of the primary coil. the current produced is in miliamps. not enough to hurt someone but certainly enough to dammage a fluke multimeter.
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#17 User is offline   System Tech Senior 

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Posted 08 February 2010 - 03:29 PM

So when I answered with nothing was I right?
Jason C.
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#18 User is online   olo131 

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Posted 31 May 2010 - 05:01 PM

Damn STS just has to be right even if he doesn't know what the hell he's talking about!!!!

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