Square-D GF Test

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augie47

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I had a situation arise today where I think the info is totally false but thought I would run it by folks familiar with Square-D I line switchboards.
On a new install, I asked for documentation of the GF test on a 1600 amp Main in accordance with 230.95(C).
The electrician advises that the Square-D rep can test the breaker with his "computer" but pressing the "test" button on the breaker will not cause the breaker to trip unless the load is 30%.
Never heard of such. Any validity to the statement ?
 

shortcircuit2

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South of Bawstin
There is more to it than that. Inspection and Performance Testing needs to be done prior to the equipment being energized. This is done by a third party testing company that is NETA certified.

Also,under 2014 NEC 240.87, a means for Arc Energy Reduction is required.
 

augie47

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There is more to it than that. Inspection and Performance Testing needs to be done prior to the equipment being energized. This is done by a third party testing company that is NETA certified.

Also,under 2014 NEC 240.87, a means for Arc Energy Reduction is required.

On dozens of jobs in the last few years, manufacturers reps have come out, plugged their little computers into the breaker interfaces (removing no covers) and trip tested.
Is that not a proper method.
(230.95 simply says "performance tested" with no details)
 

zog

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Location
Charlotte, NC
On dozens of jobs in the last few years, manufacturers reps have come out, plugged their little computers into the breaker interfaces (removing no covers) and trip tested.
Is that not a proper method.
(230.95 simply says "performance tested" with no details)

That is only testing the relay, it does not test the entire system, the CT could be installed backwards or cables/bus routed improperly and still pass the method they are using.
 

mayanees

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Westminster, MD
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Electrical Engineer and Master Electrician
NETA ATS

NETA ATS

The breaker should be tested to the NETA Acceptance Testing Standard for its first test, then NETA Maintenance Testing Standard for subsequent tests. The main difference between the tests is that the acceptance test specifies primary current injection, thereby looking through the CTs, which addresses Zog's comment.
 

augie47

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State Electrical Inspector (Retired)
Interesting ! I don't doubt what is stated.

I know of so many installs that have had no test (I was not involved) and I have been involved with a fair number of systems involving engineers where the factory rep set the parameters and did the same test for GFCI.

The amount of gear that has not been field tested beyond that must be plentiful.
 

augie47

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Tennessee
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State Electrical Inspector (Retired)
The breaker should be tested to the NETA Acceptance Testing Standard for its first test, then NETA Maintenance Testing Standard for subsequent tests. The main difference between the tests is that the acceptance test specifies primary current injection, thereby looking through the CTs, which addresses Zog's comment.

Is that test routinely performed prior to shipment ?
I'm obviously in the dark on this and an simply trying to comply with NEC 230.95(C) which requires a test when installed on site !
Either it's routinely ignored or a whole bunch of folks don't understand the testing required to meet that Code section.
 

shortcircuit2

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South of Bawstin
Appendix A of the UL White Book #1 has information about Dead-Front Switchboards and part 6 covers Ground-Fault protection. Each manufacturer will supply instructions on how the testing is done along with a test form.

230.95(C) Performance Testing is done on site after installation before it is energized.

The instructions will also give other checks and inspections needed for the switchboard itself...IE torque, grounding, resistance testing.

Lashing of the SE conductors may also be required.
 

augie47

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Tennessee
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State Electrical Inspector (Retired)
Proper testing and inspection by a Qualified 3rd party company with the right equipment takes a day and costs about $2K in my area.

That part I understand and I don't think I ever seen any inspector request such a test in an effort to comply with 230.95(C). I think for the most part that section is ignored and the inspectors in this area accepted "push the button and it works" as satisfying the requirement.
I am presently unsure of the intent of 230.95(C) as far as what "testing" is required.
 

jim dungar

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Wisconsin
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PE (Retired) - Power Systems
Is that test routinely performed prior to shipment ?

It is hard to test the field installed wiring at the factory.:D

A proper acceptance testing should investigate for improper neutral-ground bonding as well as the GF relay.
 

augie47

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Tennessee
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State Electrical Inspector (Retired)
It is hard to test the field installed wiring at the factory.:D

Guess that sounded stupid (not unusual for me :)) but when he mentioned NETA testing for such things as the CT mounted backwards my mind told me one would think that might be factory tested.
Is there routinely any factory testing as far as the GF circuitry ?
 

jim dungar

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Wisconsin
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PE (Retired) - Power Systems
...when he mentioned NETA testing for such things as the CT mounted backwards my mind told me one would think that might be factory tested.
Is there routinely any factory testing as far as the GF circuitry ?

Correctly mounted, but backwards wired CTs are more commonly found on branches than on mains.
Individually mounted neutral CTs, for use with circuit breakers with internal GFP, are regularly found 'backwards' or totally ignored.

I have seen installations where only some of the conductors were run through the CT.
I recall that some field techs have said they found wiring errors on way more than 50% of installations.
 
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