Hey everyone,
NACHI.TV just released a new episode:
Episode 86 - Commercial Inspection Training: Electrical - Parts 1 thru 12 (Preview)
Learn how to perform commercial inspections of the electrical system of commercial properties by an expert trainer. There are 12 Parts to the course. More information, visit http://www.nachi.org/commercial-inspections.htm
Watch this episode now. Reply here to discuss.
Chris,
I just wanted to point out a few extra items for the guys as they watch that video to maybe help them a little more as well. As you watch the video my additional notes will be in the order as they appear in the video.
1.) In regards to the gaps around the conduits entering the building at the "LB. While it most certainly needs to be mentioned to the owner that rodents and moisture can enter the building…electrically speaking the issue about temperature changes efects the raceway itself in terms of sealing…not the gap around the pipe. If their is a change of extreme temperature changes then sealing the conduit from inside the conduit with sealent will keep moisture within the conduit from forming on the inside portion of the conduit due to temperature changes and condensation and so on.
2.) Exterior illumination while a wonderful thing is not actually required at the entrances of commercial buildings like it is in a residential building. If an path of egress is required to the public way then we have level of expectation to provide that but in knowing this building ( and I do know which one it is ) the occupancy load would not require this path and so on…but call it out if you wish.
3.) Just need to clear up that “EMT” is not “RIGID” Conduit. It was mentioned that way in the video so I wanted to make sure everyone knew their was a difference so as not to call it out incorrectly to the potential buyer.
4.) Ground rods ( and I can hear Chicago laughing at me know ) come in 5/8" and 1/2" depending on if listed or not…I believe 3/8" was mentioned and they dont come in 3/8" so just wanted to make sure everyone was clear on that.
5.) At this point a 3-phase disconnect was opened and I would recommend that all watches and eye wear be used when examining all disconnects and panelboards and in commercial applications switchboards a well …better to be SAFE than DEAD !
6.) FYI- All ground rods are not copper only as stated…keep in mind that they can also be stainless steel, zinc coated steel as well as copper…just be aware of it.
7.) Don’t forget that even something as simple as a missing rivot on the exterior Nema 3R disconnect switch is important…if the cover wont close properly then it has lost it’s NEMA 3R status theoretically…Did I spell that right…lol…call it out fellas.
8.) When speaking about the overhead service conductors and the connected of the grounded conductor…indeed it does not have to be insulated or covered in terms of the change over from the utility service drop to the premise wiring BUT you need to make sure the location of the splice is not resting on a gutter or the service riser conduit as well…and that it is up atleast 18 inches from the surface covering…remember the grounded conductor carries current also…remember that !
9.) When talking about the street light…if that is supplied from the utility side then you can mention it if you wish but it wont matter…the property owner may not own it and can’t do anything about it…keep your report to the premise content.
10.) Now I notice the instructor ( which did a good job BTW ) said that the smaller panel inside is a sub-panel and did not refer to the larger panel as also a sub-panel…now we all know that the term “sub-panel” is not correct…but we use it anyway so thats fine…they are actually remote distribution panels…but I digress…the larger panel was refered to as the main panel but it is not…the disconnection for this panel is outside so it is not a main panel…but it is a remote distribution panel and treated as such…ie: seperation of grounded and grounding with in the enclosure. Now this panel was not opened because it was missing a few screws…guys…OPEN this panel, it looked in ok shape with no rust, cover seemed to to firm in place…I would have opened it and I expect you to as well unless of course you are not doing the electrical inspection and are only a facilitator but again I dont understand that premise…I can teach anyone to inspect 3-phase so I say open it…no more dangerous than the disconnect outside that was opened…ok…moving on.
11.) In regards to the illumination of a path of egress…be careful here guys…do an electrical inspection and keep it at that unless you know 100% what the building use is…for example…in a use group B construction ( business ) if I have a building with an occupancy less than 50 people and no paths over 75’ then no path of egress illumination is required…now it starts to get tricky after that but again stick with what you know and not what you can speculate.
12.) A statment was made that the emergency exits needed a emergency circuit or generator I believe or maybe a dedicated circuit to be proper…the fact is this, if this building only requires exits for illumination and have a battery backup built in then it would be fine…if unit equipment ( refered to as frog lights i believe, i cant remember ) is required then the minimum safety standard says they have to be supplied by the normal lighting circuits that supply that given area…if more than 3 normal lighting circuits are present then and only then can i run a dedicated supply to the unit equipment luminaries ( ie: bug eye type egress lights )…hope I cleared that one up with a little more information.
13.) I regards to the fire alarm system…again unless you know the use group and so on with the building in question be careful on saying anything regarding this…many buildings do not require a fire alarm system…for example most B groups do not require a fire alarm system unless a specific amount of occupants are encountered…so indeed let a fire alarm specialists take care of that…nice way to get egg on your face to say the building needs a fire alarm system only to find out it does not…dont guess…know the facts guys…please.
14.) In regards to supporting low voltage cables with tie wraps to other raceways…while tie wraps are acceptable…it is not acceptable to connect or support them to other raceways…they must be supported by the buildings structure as defined in NEC 720.
With that said…excellent video and I just wanted to add some additional important information that may help you guys as you venture into commercial electrical inspections. You are not CODE GUYS and don’t need to be to appreciate understanding how a minimum safety standard is applied.
yes. exactly.