Basic Electrical Inspection Guide
Standards of Practice
The International Standards of Practice for inspecting the electrical system is located at www.nachi.org/sop.
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Weatherhead
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Observation
Not minimum 13' height (NEC) above floor.
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Observation
No bushing (phenolic insulator).
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Observation
Inadequate drip loop.
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Observation
Improper splices.
Illegal line-side tap (inside soffit).
Mast
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Observation
Inadequate attachment to wall.
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Observation
The mast is electrical metallic tubing (EMT) which is NOT an acceptable material. The mast should be of:
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Intermediate metal conduit (IMC); or
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Galvanized rigid conduit (GRC). Samples of each are attached to the wall.
Meter
Observation
The amperage rating of the 3/0 (225-amp) copper service entrance conductors exceeds the amperage rating of the electric meter socket enclosure (135 amps) as viewed on the meter label.
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Observation
The bonding bushing conductor is in contact with phase lug.
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Note:
Also attached to the wall is a section of polyvinyl chloride (PVC) conduit that is NOT acceptable as electrical mast material.
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Electrical Panels-Panel #1 (Service Panel)
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Observation
Description: GE 200-amp Main Breaker Panel with a 200-amp main disconnect (no other breakers).
Observation
Observation
Panel/components are not connected to a service grounding system (SGS) SGSs include:
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Grounding electrode conductor (GEC);
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Grounding electrode (examples: driven rod(s), concrete encased, grounding ring/plate, water pipe where acceptable).
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Observation
Main lugs are double tapped to feed panel #2.
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Observation
Panel/components are not connected to a service grounding system (SGS).
Distribution (sub-) Panel
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Observation
The 200-amp service panel is inadequate for feeding the 200-amp.
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Observation
Observation
A main bonding jumper connecting the neutral and grounding bus bars should be installed in the service panel only (point of first disconnect).
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Observation
No conductors attached to bonding bushings.
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Observation
Main feed conductor over-stripped (1" max. according to label).
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Observation
A cable connector should be installed to protect the conductor insulation from abrasion.
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CONDITIONS NOT DEFECTS:
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Observation
The amperage rating of the 3/0 (225-amp) copper feeders exceeds the 200-amp maximum rating of the load center.
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This is acceptable as long as the amperage rating of the main disconnect does not exceed the amperage rating of load center.
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Observation
Multiple grounds under the same screw.
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Observation
Vinyl insulation extends several inches into the panel.
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Observation
Pig-tailed breaker.
Distribution (sub-) Panel
GE 100-amp Main Breaker load center with no main disconnect. Backfed by 125-amp breaker. Circuit breakers are installed.
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Observation
Unfilled holes.
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Observation
Missing cable connector.
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Observation
Deadfront cover attached with improper screws.
Sharp, course-thread screws can cut conductor insulation potentially causing a dangerous arc flash.
Observation
Deadfront cover missing filler plates (twistouts).
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Observation
The amperage rating of the 125-amp backfeed breaker exceeds the 100-amp maximum amperage rating of both the #4 copper feeders and the load center.
The 125-amp backfeed breaker has no retaining device.
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Observation
No bonding bushing.
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Wherever feeders enter or leave a load center through concentric knockouts, a bonding bushing must be installed to ensure electrical continuity of the bonding/equipment grounding system. Bonding bushings should be connected to the neutral bus bar.
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Observation
No insulated bushing is installed to protect feeders against abrasion where they enter the load center.
Observation
Observation
Multiple 20-amp breakers are connected to 14-gauge conductors. 20-amp breakers should be connected to 12-gauge conductors.
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Observation
The GFCI breaker is connected to the grounding bus bar, not the neutral bus bar.
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Observation
Multiple neutral conductors under the same screw in the neutral bus bar.
This is wrong because it complicates isolating the neutral for one of the circuits involved.
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Observation
Pig-tailed neutrals.
Again, this is wrong because it complicates isolating the neutral for one of the circuits involved.
Observation
Neutral conductor.
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Observation
In order to complete their insertion into the 125-amp breaker (lower right corner) the #1 (150-amp) copper conductors had strands cut away.
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Cutting strands reduces the amperage rating of a conductor. 37. Unfilled Knockout.
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Observation
Unfilled Knockout.
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Observation
Grounding conductor on the neutral bus bar.
First Detached Structure Electrical Panel
Square D 125-amp load center, backfed by 125-amp breaker.​
Grounding conductors of different gauges under the same screw. The 125-amp backfeed breaker has no retaining device. Neutral and grounding bus bars are not isolated from each other.
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Second Detached Structure Electrical Panel
Neutral and grounding bus bars are not isolated from each other.
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Observation
