Surge protection device

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Davebones

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Have a 277-480 volt Y system . When installing a surge protector they show tying into each phase and then to the neutral . What should you do if there's only 3 phases at a disconnect and no neutral pulled there ? Tie the neutral connection shown to ground at that point ?
 
Davebones said:
Have a 277-480 volt Y system . When installing a surge protector they show tying into each phase and then to the neutral . What should you do if there's only 3 phases at a disconnect and no neutral pulled there ? Tie the neutral connection shown to ground at that point ?
Click to expand...

How do you have 277 without a Neutral? Where are you putting the SPD?
 
Davebones said:
Have a 277-480 volt Y system . When installing a surge protector they show tying into each phase and then to the neutral . What should you do if there's only 3 phases at a disconnect and no neutral pulled there ? Tie the neutral connection shown to ground at that point ?
Click to expand...

Get the correct suppressor. They do make them without a neutral.
Not sure what it will do if you connect as you ask.
But I can tell you the smoke gets out if the neutral of the suppressor is not connected to a bonded neutral of the system.
 
I think more details on the unit used as well as instructions for it are necessary to be able to answer the question.

A start at guessing however may depend on what colors the leads are or the markings of the terminals if no leads. If you have white lead it may be intended to connect to a neutral and a green lead likley intended to connect to equipment ground. Both white and green leads probably means it has MOV's between netural and EGC as well as to ungrounded leads.

My guess is if there is no neutral present that most of them don't hurt anything to connect to the EGC, but if you have both neutral and EGC present your protector should probably have a lead for both.
 
Davebones said:
The surge protector device is a Eaton CVX050-480D .
Click to expand...


CVX050
230L Single-phase two-wire + ground 200, 208, 220, 230, 240, 277 — 320 640 320 — 1200 1200 1200
480L Single-phase two-wire + ground 380, 400, 440, 460, 480 — 550 1100 550 — 1800 4000 1800
240S Split-phase three-wire + ground 100/200, 110/220, 120/240 300 150 300 150 1200 700 1200 800
208Y Three-phase wye (star) four-wire + ground 100/175, 110/190, 120/208, 127/220 300 150 300 150 1200 700 1200 800
480Y Three-phase wye (star) four-wire + ground 220/380, 230/400, 240/415, 277/480 640 320 640 320 2500 1200 2000 1200
600Y Three-phase wye (star) four-wire + ground 305/525, 347/600 840 420 840 420 2500 1500 2500 1500
240D Three-phase delta three-wire + ground 200, 208, 220, 230, 240 640 — 320 — 2000 — 1200 —
240H Three-phase high leg delta 240 300 150 150 640 1500 700 1200 700
480D Three-phase delta three-wire + ground 380, 400, 415, 440, 480 1100 — 550 — 3000 — 1800 —
600D Three-phase delta three-wire + ground 525, 600 1100 — 700 — 3000 — 2500 —
048DC Direct current 48 Vdc b 130 — 65 — — — — —
125DC Direct current 125 Vdc b 288 — 144 — — —

It appears you have delta units.
You should be good to go.
 
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Davebones said:
The surge protector device is a Eaton CVX050-480D .
Click to expand...


qcroanoke said:
CVX050
230L Single-phase two-wire + ground 200, 208, 220, 230, 240, 277 — 320 640 320 — 1200 1200 1200
480L Single-phase two-wire + ground 380, 400, 440, 460, 480 — 550 1100 550 — 1800 4000 1800
240S Split-phase three-wire + ground 100/200, 110/220, 120/240 300 150 300 150 1200 700 1200 800
208Y Three-phase wye (star) four-wire + ground 100/175, 110/190, 120/208, 127/220 300 150 300 150 1200 700 1200 800
480Y Three-phase wye (star) four-wire + ground 220/380, 230/400, 240/415, 277/480 640 320 640 320 2500 1200 2000 1200
600Y Three-phase wye (star) four-wire + ground 305/525, 347/600 840 420 840 420 2500 1500 2500 1500
240D Three-phase delta three-wire + ground 200, 208, 220, 230, 240 640 — 320 — 2000 — 1200 —
240H Three-phase high leg delta 240 300 150 150 640 1500 700 1200 700
480D Three-phase delta three-wire + ground 380, 400, 415, 440, 480 1100 — 550 — 3000 — 1800 —
600D Three-phase delta three-wire + ground 525, 600 1100 — 700 — 3000 — 2500 —
048DC Direct current 48 Vdc b 130 — 65 — — — — —
125DC Direct current 125 Vdc b 288 — 144 — — —

It appears you have delta units.
You should be good to go.
Click to expand...

That might mean it has higher clamping voltage to ground then the 480Y unit, and that the 480Y unit could still be acceptable and provide a lower clamping voltage to ground as that voltage will still be 277 volts even though there is no neutral in use for the OP.
 
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SPD

SPD

Davebones said:
The surge protector device is a Eaton CVX050-480D .
Click to expand...

The D on the end of the cat# indicates it is designed for a Delta system, not the Wye system (3phase, 4wire) you are describing. So you should only have 3 phase wires and a ground coming from the unit. Not sure if it is the correct one to use here, even though the phase voltage matches. Maybe someone can answer that.
IMO a better place to install these would be the closest to the equipment you are trying to protect. i.e. the input terminals inside the VFD's.
 
That's the question I wondered was it ok to use a unit that was marked for a Delta when the system we have is a Y , it's just we don't have a neutral connection pulled as we only needed three phase . We are a industrial facility so we would install it at a disconnect which is right next to the VFD's . I tried calling the manufacture but got tired of waiting so I e-mailed them but we are still waiting on a reply ...
 
Davebones said:
That's the question I wondered was it ok to use a unit that was marked for a Delta when the system we have is a Y , it's just we don't have a neutral connection pulled as we only needed three phase . We are a industrial facility so we would install it at a disconnect which is right next to the VFD's . I tried calling the manufacture but got tired of waiting so I e-mailed them but we are still waiting on a reply ...
Click to expand...

I found this post that may interest you.

http://forums.mikeholt.com/showthread.php?t=169566
 
Davebones said:
The surge protector device is a Eaton CVX050-480D .
Click to expand...

On the surface your original question seems so simple-just get the correct device. But after looking at the docs for this product the answer does not seem to be apparent. In fact it raises even more questions for me. What if you had a 480/416 center tapped 3 phase system which model would you use? Or a 240/480 single phase system? Or a 480 delta corner grounded system? Does the 480 delta model you are looking at imply an ungrounded system? Funny how something so seemingly simple can get so complex.
 
Davebones
This is the answer I got from a GE applications engineer:

"I think we would apply an SPD designed for 3W delta application in equipment supplied from a 3W solidly grounded feeder. We don’t distinguish 3W delta from 3W grounded-wye."

Tony
 
Since OP's application doesn't utilize a neutral, either the Y or D unit could probably be used. The Y unit will likely have lower clamping voltage to ground though.
 
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