Two Questions; Calling all Electricians

[ctrane]

First, is there a list of typical items that are considered continous, by NEC definition. I am trying to see if I have uncessarily been multiplying certain pieces of equipment with the 1.25 multiplier.

Secondly, my question is for electricians. I have been working with an extremely talented electrician for a design/build job. He gives me insight into what the man in the field does and does not like. One point he makes is that he finds that drawing circuit lines all over the place with wire counts is ignored in the field. As an example, now for site lighting on his job, I show the fixtures with a circuit number next to it, and that's it. I then performed a voltage drop on the longest run, with the fixtures daisy chained, and found that it was within NEC guidlines. I feel that I am to perform the engineering part, and I am to assume that at the very least a journeyman is overseeing the job, and it is his duty to get the appropriate pipe and wire out to the fixtures. Is this right or wrong? Please, any and all opinions/insight will be appreciated.

 

[petersonra]

I am not an electrician but I think on a design build type situation what you are doing is fine. People in the field tend to do as they please anyway so it is best not to make things unnecessarily complicated for yourself. Normally you will need to have some kind of as-built drawings afterward and you really do not want to have to revise anything you don't have to.

This approach will not always work though because there are times when you are going to have to tell them to ran a wire from point A to point B and here is a drawing showing where the raceway is with elevations and sections. Not common maybe, but it will happen.

Judgment call.

 

[ctrane]

First, thank you for the reply. I am quite young to the industry, and these kind of questions are not the kind you can look up in a book, so I greatly appreciate the wisdom of elders of the industry. I try to show drawings as clean as possible, and if I feel the situation unusual, or special (for instance feeders), I like to show more info., but I feel branch circuits, on the most part, are cut and dry. Again, thank you for the help.

 

[GalwayElectric]

I would agree with the lines all over the print is not really necessary. If you designate what's required or "specked" for the circuit (pipe size, disconnect size (if applicable), etc...) then the actual run can be and usually must be figured on the job, IMO.

Continuous means on for 3 hours or more. Lights, motors (most), hot water heater, HVAC, etc... I'm not sure if there is a list that you are referring to. Maybe you can make one and share it with us here?

 

[bphgravity]

The code does define some equipment as continuous loads such as water heaters - 422.13 and fixed electrical space heating equipment - 424.3(B).

Otherwise, it's mostly a common sense and "as designed" consideration. Obviously most commercial lighting is continuous.

 

[dlhoule]

First, thank you for the reply. I am quite young to the industry, and these kind of questions are not the kind you can look up in a book, so I greatly appreciate the wisdom of elders of the industry. I try to show drawings as clean as possible, and if I feel the situation unusual, or special (for instance feeders), I like to show more info., but I feel branch circuits, on the most part, are cut and dry. Again, thank you for the help.

Who are you calling an elder? I'm only 64.

 

[charlie b]

I do not like the convention of showing a number of tick marks on each arc to represent the number of phase, neutral, and EGC conductors in each section of the run. I think it is a waste of time, that it is an open invitation to errors (and to change orders), and that it will be ignored by the installer anyway.

When I lay out circuits for an office-type building, I prefer to show the circuit number at each outlet, and to show arcs from outlet to outlet, and to show a home run symbol (arrow) with a label showing the panel name and the 3 circuits used in the run. I make an effort to balance the loads, and to make sure that loss of a single circuit does not kill power to every outlet in any single room. I like to hope that this is followed faithfully by the installer, but then I also like to hope that my lottery numbers will get picked tonight.

 

[Mudder]

My firm's policy is to only show conduit and wire for atypical runs and for site work. For interior work, we just show circuit numbers next to devices.

We used to show conduit between everything, but as you said, we found that contractors just did whatever they wanted anyway, so it wasn't worth the trouble.

 

[Ted Haefner]

My firm also only shows the circuit and panel number next to the device, light, HVAC equipment, etc. Checking voltage drop on the longest run is good pratice.

 

[ctrane]

Thanks to all who have replied. Your input helps me a great deal in shaping my presentation and content. A special thanks to the elders!

 

[iwire]

One point he makes is that he finds that drawing circuit lines all over the place with wire counts is ignored in the field.

You bet it is.

I will give you my opinion as an installer.

Don't waste your time or clutter the print itself with a lot of specific instructions.

If there are odd / unusual items give me a detail print (not on the floor plan) of what you want. Remember I can not read your mind.

Tell me the the circuit and panel designations at each location. I will determine the best routing and methods in the field based on the job specifications.

Put a specification limiting voltage drop and I will follow that.

In other words don't worry to much about the small stuff. I can handle figuring out how to route and wire branch circuits.

Provide clear specifications for any specific requirements that are actually important to the finished project.

No MC or 3/4" EMT minimum, all outside conduits to be RMC etc.

Lastly insist that the specifications be followed, many ECs try to save money by ignoring the specifications.

 

[hardworkingstiff]

Lastly insist that the specifications be followed, many ECs try to save money by ignoring the specifications.

I cannot agree with this more. If time is spent writing specifications and they are not enforced, you reward the contractor that does not follow them, penalize the one that does (did not get the job because his price was too high from bidding the specs), force the customer to pay a higher price for the work performed than he/she should have, and force the customer to pay for time writing specifications that were not observed/enforced.

 

[ramdiesel3500]

I have started placing the electrical specifications directly on the plans. This seems to make it clear that I intend for them to be followed and it eliminates the confusion of having both a roll of plans and a book. This may not be practical for a large job, but it works well for me on small jobs and I believe the contractors appreciate it!

 

[petersonra]

No MC or 3/4" EMT minimum, all outside conduits to be RMC etc.

What do you have against using MC? I would never spec it for anything I do, but it might be appropriate?

Or prohibiting 1/2" EMT? I don't like it. Most of my stuff is control wiring. Near imposible to snake another wire in a 1/2" conduit.

Or use of RMC outside? Whats wrong with specing RMC for outside use? I might spec EC choice RMC or IMC, but that would be the two chocies, unless I was worried about corrosion.

You probably would hate my spare wires, spare conduit, and pulling string requirements.

Lastly insist that the specifications be followed, many ECs try to save money by ignoring the specifications.

Yep. They know once they have been paid, it is difficult to do much about it. OTOH, I am not opposed to having a cost saving measure pointed out either up front or after the bid has been awarded.

I am not even opposed to a deviance request. But ignoring the specs is not acceptable.

 

[don_resqcapt19]

Bob,

You probably would hate my spare wires, spare conduit, and pulling string requirements.

I hope you don't specify a pulling string in with conductors. In many cases the use of that string will damage the existing conductors. I hgve found that a spare conductor works much better for pulling in additional conductors.
Don