jar546
CBO
You are looking at a generator. What is wrong?
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Name that electrical VIOLATION 15 July 2019
- Thread starter jar546
- Start date
chris kennedy
ADMIN
How would that apply to a generator?
Not sure I understand why it has to be in the middle? or how that can be determined by the photo.
Not an electrical inspector, thankfully L&I handles electrical in WA.
However, the high leg is supposed to be orange and the plate with the red-oxide paint has sharpie indicating that L3 is the high leg. High leg has to be on the "B" phase.
408.3(E) Bus Arrangement.
(1) AC Phase Arrangement. Alternating-current phase arrangement on 3-phase buses shall be A, B, C from front to back, top to bottom, or left to right, as viewed from the front of the switchboard, switchgear, or panelboard. The B phase shall be that phase having the higher voltage to ground on 3-phase, 4-wire, delta-connected systems. Other busbar arrangements shall be permitted for additions to existing installations and shall be marked.
(2) DC Bus Arrangement. Direct-current ungrounded buses shall be permitted to be in any order. Arrangement of dc buses shall be field marked as to polarity, grounding system, and nominal voltage.
(1) AC Phase Arrangement. Alternating-current phase arrangement on 3-phase buses shall be A, B, C from front to back, top to bottom, or left to right, as viewed from the front of the switchboard, switchgear, or panelboard. The B phase shall be that phase having the higher voltage to ground on 3-phase, 4-wire, delta-connected systems. Other busbar arrangements shall be permitted for additions to existing installations and shall be marked.
Exception: Equipment within the same single section or multisection switchboard, switchgear, or panelboard as the meter on 3-phase, 4-wire, delta-connected systems shall be permitted to have the same phase configuration as the metering equipment.
Informational Note: See 110.15 for requirements on marking the busbar or phase conductor having the higher voltage to ground where supplied from a 4-wire, delta-connected system.
(2) DC Bus Arrangement. Direct-current ungrounded buses shall be permitted to be in any order. Arrangement of dc buses shall be field marked as to polarity, grounding system, and nominal voltage.
jar546
CBO
OK, great conversation but let's look at this a little closer.
The first scenario is that this generator just happens to output the 208 high leg on the C phase. This is a good time to question the electrician who is changing the ATS and ask if he checked phase rotation and if he verified that the high leg was indeed coming off of the C phase.
Scenario two is possible that the electrician did verify that this generator high leg does come off the C phase so he marked it appropriately and THEN he placed it on th B phase in the ATS to match what was done before and phase rotation.
Another scenario is that, well, the electrician's helper simply does not know and just marked the wrong wire as the high leg. Either way, when doing this inspection, you will have to ask a lot of questions.
However, what phase a generator produces the high-leg is not covered by the code, where it lands on a bus is certainly relevant.
Thoughts?
The first scenario is that this generator just happens to output the 208 high leg on the C phase. This is a good time to question the electrician who is changing the ATS and ask if he checked phase rotation and if he verified that the high leg was indeed coming off of the C phase.
Scenario two is possible that the electrician did verify that this generator high leg does come off the C phase so he marked it appropriately and THEN he placed it on th B phase in the ATS to match what was done before and phase rotation.
Another scenario is that, well, the electrician's helper simply does not know and just marked the wrong wire as the high leg. Either way, when doing this inspection, you will have to ask a lot of questions.
However, what phase a generator produces the high-leg is not covered by the code, where it lands on a bus is certainly relevant.
Thoughts?