gfci and pump 208 v

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domnic

Senior Member
Occupation
Electrical Contractor
I want to install a gfci for a 208 v pump a 20 amp 2 pole gfci breaker 20 feet from the pump the panel is 120 feet away the wire to the pump is 2 hots and one egc how can I wire the gfci with no neutral ?
 

cpinetree

Senior Member
Location
SW Florida
No neutral wire from pump to breaker. Leave it empty.
Neutral pigtail from breaker to neutral in panel.
Ground from pump to ground bar in panel.
 

domnic

Senior Member
Occupation
Electrical Contractor
pump

pump

I want to put the gfci in line with the 2 hots and a egc the conduit is full I cant pull more wire they want gfci 20 feet from pump the panel is 100 feet from where they want the gfci.
 

domnic

Senior Member
Occupation
Electrical Contractor
I would check the GFCI because most are rated 120v/240v not 208V. I believe they make them 208V

A two pole GFCI in a 120/240 volt or a 120/208 panel would work the same the gfci works on 120 volts of each leg.
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
A two pole GFCI in a 120/240 volt or a 120/208 panel would work the same the gfci works on 120 volts of each leg.
But if the manufacturer has not done the required UL tests in the 120/208 configuration they will not sanction it's use in that configuration and an AHJ is likely to reject it as contrary to listing.
To the OP: AFAIK there are no 240V GFCIs sold in the US that will work without a line side neutral.
If you can find a two pole 240V breaker which does not have a neutral pigtail it should work, but you might need a new panel near the load to mount it in.
 

JFletcher

Senior Member
Location
Williamsburg, VA
A two pole GFCI in a 120/240 volt or a 120/208 panel would work the same the gfci works on 120 volts of each leg.

There is a 32V differential in potential as well as 3ph being 120* between hots vs 180* for 120/240V. GFCI may not care about that but there have been threads here re: 120V AFCI breakers not working correctly/rated for 208V service.

You have to have a line side neutral. Since you dont, you have to pull one. Since you cant, you will need a GFCI breaker in the main panel to protect your pump with a 3 wire setup. or find a way to get a neutral in that conduit, like removing unused/abandoned wire, or converting branch circuits to a MWBC. or run a new conduit.
 

domnic

Senior Member
Occupation
Electrical Contractor
There is a 32V differential in potential as well as 3ph being 120* between hots vs 180* for 120/240V. GFCI may not care about that but there have been threads here re: 120V AFCI breakers not working correctly/rated for 208V service.

That has nothing to do with how a gfci works.
 
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JFletcher

Senior Member
Location
Williamsburg, VA
That has nothing to do with how a gfci works.

Which I stated, not clearly enough. The main point that I (and GoldDigger in the post before) was getting at is that a 2p GFCI breaker may not be rated or listed for 208V. Some are, like this one:

"The Siemens 2-pole GFCI circuit breaker can be installed on a 120/240V AC single phase, 3 wire
system, the 120/240V AC portion of a 240/120 volt, 3 phase, 4 wire system, or on a 208Y/120 volt, 3 phase, 4 wire system. When installed on these systems, protection is provided for 2 wire, 240V AC or 208V AC circuits; 3 wire, 120/240V AC circuits."

Irrelevant here, but noteworthy, is that the 120V 1p breakers are not listed for 120/208V.

As for the rest of my post, it was on point to the question you asked:

"how can I wire the gfci with no neutral ?"
 

iwire

Moderator
Staff member
Location
Massachusetts
Which I stated, not clearly enough. The main point that I (and GoldDigger in the post before) was getting at is that a 2p GFCI breaker may not be rated or listed for 208V. Some are, like this one:

"The Siemens 2-pole GFCI circuit breaker can be installed on a 120/240V AC single phase, 3 wire
system, the 120/240V AC portion of a 240/120 volt, 3 phase, 4 wire system, or on a 208Y/120 volt, 3 phase, 4 wire system. When installed on these systems, protection is provided for 2 wire, 240V AC or 208V AC circuits; 3 wire, 120/240V AC circuits."

Irrelevant here, but noteworthy, is that the 120V 1p breakers are not listed for 120/208V.

As for the rest of my post, it was on point to the question you asked:

"how can I wire the gfci with no neutral ?"

:thumbsup:
 

brantmacga

Señor Member
Location
Georgia
Occupation
Former Child
Which I stated, not clearly enough. The main point that I (and GoldDigger in the post before) was getting at is that a 2p GFCI breaker may not be rated or listed for 208V.

Do you know off the top of your head any that specifically aren't rated for 208Y/120?

I've seen 2-pole AFCI's that specifically say they aren't rated for that voltage, but I can't recall any 2-pole GFCI's that aren't.

Good to know though

Thanks


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kwired

Electron manager
Location
NE Nebraska
Standard 2 pole breakers are only listed 120/240 yet we use them on 208 quite often.

The 120 degree phase angle doesn't affect operation of a GFCI, but does give AFCI's problems.

There are 240 volt GFCI breakers with no neutral - they can only supply 240 volt two wire loads. QO 60 amp GFCI's are one that I am aware of that only listed in the catalog with no neutral. OP could use one of those if nothing else is available primarily for GFCI protection and have proper overcurrent protection somewhere upstream.
 

brantmacga

Señor Member
Location
Georgia
Occupation
Former Child
Standard 2 pole breakers are only listed 120/240 yet we use them on 208 quite often.

I did some research in the digest and this is what I have found .....

So, the QO data sheet says that breaker is rated for 120, 208Y/120, 120/240, and 240v; in the same line it says the breaker is rated for 48Vdc, but elsewhere in the digest it says you can order it rated for 48Vdc.

Interestingly, the digest gives no UL listed trip curves for 208Y/120, but does so for all other voltages.

Also, when you go to the product selector for GFCI's and select 208Y/120, the only breakers it shows as listed for that voltage are 3-pole.

We use factory built gear packages all the time that are installed on 208Y/120 and full of GFCI's; I will look next time and see if any breaker there is actually listed for the voltage.

Fascinating.


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