Do Electrical Engineers understand three phase reality?

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infinity said:
If the engineer over designs a system, why should the installer care? If he's getting paid to do work beyond the scope of the NEC so be it. The only one that should really care is the guy who is paying the bill. He may be getting a lot more than actually necessary and paying for it too.
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I don't design buildings, but every control system that I do design includes whatever I feel is necessary to support future needs without costing the end user an insane amount.

Contractors seem to be oriented towards cheap-as-possible, because that is often how they get the jobs in the first place, so it is understandable. Often they underbid and try to find some way around meeting the specs to lower their costs.

I usually specify minimum 3/4" conduit because I have seen what happens in the field when you pull wires through a 1/2" conduit for a few hundred feet. Just trying to get 4 wires pulled through it is a major effort.

Same reason I almost always spec minimum #12 to be pulled, even for control wiring that maybe on a 5A circuit. It is far more likely a #14 will be damaged in pulling than a #12.

Same thing with spares. I don't want to pay $5000 to run an extra wire that needs to be run down the road when for a few bucks it could have been put in when the original work was done.

I have been involved in projects where the change orders for the install exceeded the original amount the EC bid because the customer wanted the cheapest possible install. Often they bid it out themselves without any spec, sometimes even before drawings were available laying out what wires had to go where. Thats not an unusual situation and is why I usually put in a fair amount of capacity for things I don't even know about yet.

In fact, many customers have decided to forgo even having us come up with installation drawings, thinking the the few grand it might cost is a waste of money. They just give the schematics to the EC and say "wire it up". Often the EC's people cannot even read the schematics, which leads to "interesting" situations. I try not to laugh or tell them "I told you so", but it is hard.

The ECs laugh all the way to the bank.
 
I once did a design review for a government project located somewhere south of my present home. So as not to get the Forum members from that city or state all riled up over a waste of their tax money, I'll not name the exact location.

My task was to review for technical accuracy and adequacy, as well as for compliance with their design standards. When I read the standards, I was shocked. I could try to tell you that they wanted every circuit to be upsized one level from the ampacity (i.e., #10 for 20 amp circuits), and 100% spare room in any conduit, and 100% spare conduits in any underground duct bank, and a bunch of other outlandish things. But then you would say, "No way, you are just pulling our collective legs." To that I would reply, "Way. In fact, I believe I am understating their requirements for over-designing."

Anyone who came to them with "good ideas" for saving money by "value engineering" the project would be immediately kicked off the project. They had heard it all before, and they had made their choices. They believed that the potential cost savings for a future project outweighed the present day cost of over-design.
 
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I am not surprised Charlie. People have learned that so called "value engineering" really means "you will pay through the nose later".

The first time someone gets a bill for $5000 to run a single additional wire because there were no spares and no room in the conduits, they realize that maybe that extra 5 or 10% upfront is a bargain.

I once had an EC forget to put the spares in one of his conduits. When it was discovered, he eventually decided it would cost him less to run another conduit alongside it rather than try to get the spares in the existing conduit. The end user was kind enough to go with my suggestion of putting one pulling string in the spare conduit rather than any wires.

Same thing with bringing in power to a machine. Maybe a 70 A BC is adequate today, but who knows what power might be needed down the road? Once you bring power to an area of a plant that currently has none, maybe it makes sense to bring a 200A BC in to accomodate future machines that will no doubt be installed down the road. A new PB can be real handy sometimes, in case you need to add some outlets or lighting in the area. yea, maybe it costs a little extra in the machine installation cost, but people can't work in the dark and electrical outlets are something you almost have to have around a machine. All kinds of need for outlets tend to pop up when you put a machine in.
 
It's not always the engineer either. I was recently asked to do the electrical for a pump house for a sports field in a city park.

Someone from the city said they wanted a 600A, 480V service. They might add some lights later. (This was a 10HP pump, by the way.) They never asked my opinion, but I said I think something smaller would suffice. They said OK, but put in an alternate for 600A.

Of course, the 600A was only a few thousand more. So they paid for it. I am supprised the POCO gave it to them. They probably set a 30KVA transformer.

Steve
 
This is a good point about two engineers being involved. There is one in Indiana and another in California. And then there is this "inspector". I don't deal with this "inspector". My foreman, Mark, does. And that is what he tells me. Whom am I to believe?
Someone mentioned that they can't include their reasons for doing something a certain way on their drawings. This is too bad since the ultimate intention is left out. There is some sketch of a design for a swing on an oak tree floating around the Internet which illustrates this point. Something is lost in the communication. There are about 50 circuits in this installation and most are listed as 1/2" conduit runs. There seems to be no objection to combining some of these runs into a 3/4" tube.
So I design this system the most practical way I can. And I come up with this come-uppance. That's why I am frustrated. I am vaguely aware that conduit and wire cost money. And it is true that I could just squeeze about 25 1/2" conduits into the top of a 6" X 20" can.
All I really want to do is design a workable system. I don't want to end up with conduits crosing over or under each other. I am including provisions for spares.
~Peter
 
I worked on a New Target job about.. 2 years ago..
i ran nearly all the conduit in the offices section and the food court area, and pulled ALL the wire for both.

we routinely pulled (under foreman's direction) more than 3 circuits per pipe.. in some cases, we put in as many as conduit fill would allow (to say nothing for de-rating)

in the end, we turned it on, Everything worked

The First Time

and Target never sent out anyone to inspect our work to that level, and they were totally fine with the job

PS my foreman's name was Mark also
:)
 
To all engineers

To all engineers

Bob said:
In fact, many customers have decided to forgo even having us come up with installation drawings, thinking the the few grand it might cost is a waste of money. They just give the schematics to the EC and say "wire it up". Often the EC's people cannot even read the schematics, which leads to "interesting" situations. I try not to laugh or tell them "I told you so", but it is hard.

The ECs laugh all the way to the bank.
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And then we have the customers who do not want us ECs even talking to the engineer. When we tell them something won't work and they check with their great engineer and are told it will so work.

The record for me on these jobs is 14 changes to get it working. Guess what I don't do:......I do not laugh all the way to the bank. I feel any customer deserves a decent value for their money and they are not always getting it.

Now the one with 14 changes was partially customer's fault; if I had talked to the engineer at any time before the 13th change, it would have been solved with just one or two changes. Some engineers do not want any one saying something of their's isn't right or won't work and you can't talk to them about it.

Because of the few occaisions like the above, I want to send out a note of thanks to all of the better ones, the ones who have agreed that they made a mistake and corrected it graciously. To these same ones who have taken the time to explain to me why my reasoning was mistaken. And to all the ones who have done such a good job there were no mistake for me to ever catch. But you guys should make a mistake now and then just to let us know you are human too.:)
 
dlhoule said:
Bob said:


Because of the few occaisions like the above, I want to send out a note of thanks to all of the better ones, the ones who have agreed that they made a mistake and corrected it graciously. To these same ones who have taken the time to explain to me why my reasoning was mistaken. And to all the ones who have done such a good job there were no mistake for me to ever catch. But you guys should make a mistake now and then just to let us know you are human too.:)
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Bob, here's the problem I have with some ECs...they tend to act high and mighty as well, and to them an Engineer should make a MISTAKE free plan, because after all you're a PE.

When in reality, no one is perfect. I go out into the field, and I can't believe what I see, and then they're wanting mistake free plans? I think it's more about getting something that works, and working together. And to top it off, you don't know how many ECs have called me "honey" or "babe" and told me they know what they are doing. So I think there is a miscommunication problem between the two trades at times, because the same thing goes on in the field.

Now, I will say most have been very nice, and that fact that I'm a lady helps sometimes...they get really sweet and nice when I come in the field in my hard hat. But at times, it's rough...no one is trying to create a problem, just give the customer some quality work for they money.


Lady :)
 
Why would you want to confess to what amounts to fraud in a public forum like this? Just because you did not get caught does not make it right. The customer paid for what he wanted and you gave him less. Now you are bragging that you got away with it.

izak said:
I worked on a New Target job about.. 2 years ago..
i ran nearly all the conduit in the offices section and the food court area, and pulled ALL the wire for both.

we routinely pulled (under foreman's direction) more than 3 circuits per pipe.. in some cases, we put in as many as conduit fill would allow (to say nothing for de-rating)

in the end, we turned it on, Everything worked

The First Time

and Target never sent out anyone to inspect our work to that level, and they were totally fine with the job

PS my foreman's name was Mark also
:)
Click to expand...
 
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petersonra said:
Why would you want to confess to what amounts to fraud in a public forum like this? Just because you did not get caught does not make it right. The customer paid for what he wanted and you gave him less. Now you are bragging that you got away with it.
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The problem with this attitude is if you're the guy who bid against someone who isn't following the spec than he'll always get the job and you'll never get the job. His profit is driven by cutting corners so he can always underbid you and still make money. Too bad the guy paying for this work isn't paying attention. Value engineering is fine as long as it's approved by the guy who wrote the spec in the first place.
 
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