Removing old equipment

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petersonra said:
we have a winner!
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I discovered on one job - three numbers within 1% of each other and quite a bit higher than my estimate - that some bidding house had stated what the job was worth and all three basically used that number. Heavy bidding week and a small job. One of them confessed to me.

However I get a lot of very close numbers. Probably a small enough community that everybody knows the field, and my style, well enough to predict pretty closely what everybody else will do. Besides the legal issues of collusion, where is the profit? The numbers were near my prediction - which was not published.
 
dema said:
I discovered on one job - three numbers within 1% of each other and quite a bit higher than my estimate - that some bidding house had stated what the job was worth and all three basically used that number. Heavy bidding week and a small job. One of them confessed to me.

However I get a lot of very close numbers. Probably a small enough community that everybody knows the field, and my style, well enough to predict pretty closely what everybody else will do. Besides the legal issues of collusion, where is the profit? The numbers were near my prediction - which was not published.
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'prediction' or cost estimate?
public or private work for the 3 at 1%?
are you a PE?
 
Jraef said:
So much of this seems odd to me, coming from an electrical engineer...
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The installation is unusual.

High voltage cable comes into a switch in a basement electrical room. The switch has three taps. One tap feeds each of three lines. The high voltage cable goes through tunnels to each of two other electrical rooms. It is landed in gear containing a transformer that steps it down from 13.8KV to 208KV. The same line-up contains the distribution - which is partly through bus duct. So the input in each MDP is 13.8KV and the output is 208V. It is old and strange. I didn't do it.

I was referring to separating the three parts of the transformer so there would be three hunks of metal to get rid of and not one. Didn't think I'd brought up the bus duct?

I get the impression you have your dukes up, wanting to spar. I'm not much for sparring. I was asked why I thought I could get equipment in if I couldn't get equipment out. The answer basically is, "Because it is different equipment going to a different location."

There are no clear and universal definitions for high voltage. There have been many online discussions of this fact. If you are an electronics engineer then 120V is high voltage. If you are a utility engineer then high voltage is probably over 100KV for you. If you are not a utility engineer, then medium voltage probably has no meaning. My definition is that if the NEC classifies it as over 600V, then it is high voltage. Low voltage to me is 24V or therabouts - communication or control wiring that is not line voltage. In between, I call it line voltage. I don't use the term medium voltage, except to ask someone else who is using it what their personal definition is.
 
Ingenieur said:
'prediction' or cost estimate?
public or private work for the 3 at 1%?
are you a PE?
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Public job. The cost to rebid would have been more than just letting it go. So it went. Low bidder got the job and threw in a couple of little extras at no charge.
 
dkidd said:
So what is your personal definition of an MDP?
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Main Distribution Panel - the point at which the power entering the building is distributed to various feeders. It may or may not contain the service disconnect.

This campus owned its own high voltage cables and transformers. The transformers are inside the building in the MDP. You can squabble about whether or not that tranformer could really be part of the term MDP - but no matter what you call it, it is in the same line-up as the service disconnect and all the distribution breakers. The compartments are all bolted together on a single housekeeping pad. Next step down is panelboards and large motors.

So, no, I am not speaking a foreign language and I do know what you are saying - this kind of thing is more common in industrial plants. This is the only time I've seen it anywhere else. The power comes in at 13.8KV to a separate high voltage switch, the switch feeds the primary of the transformer in the gear, the transformer steps 13.8KV down to 208V, the next compartment is the main disconnect, the compartment after has the feeder breakers. Everything is together in one permanent unit in an interior basement room.
 
dkidd said:
Then the equipment you are discussing does not contain service equipment.
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What is your point?

From Wiki -

A distribution board (also known as panelboard or breaker panel) is a component of an electricity supply system that divides an electrical power feed into subsidiary circuits, while providing a protective fuse or circuit breaker for each circuit in a common enclosure.

This is the main one. Therefore it is the MDP. An MDP does not have to contain the service disconnect - the service disconnect can be on the outside of the building for example.

This one does have a main 208V disconnect in it - but the main switch for the building isn't in it. But the main switch for the building doesn't have OCP in it. So, where is the main service disconnect? What is the main service disconnect? Is there one? That's semantics and I didn't do it.

But it is definitely a main distribution panel by definition.
 
Ingenieur said:
when I did public work the Engineer's Estimate became public record
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Okay. I don't believe these are ever truly public. Different jurisdictions I guess. Are they released prior to bid? That seems to be inappropriate. Contractor should bid to the work, not to the engineer.
 
dema said:
Okay. I don't believe these are ever truly public. Different jurisdictions I guess. Are they released prior to bid? That seems to be inappropriate. Contractor should bid to the work, not to the engineer.
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yes
the number is included in the request for bids or solicitation
it's paid for with public money
 
dema said:
What is your point?

From Wiki -

A distribution board (also known as panelboard or breaker panel) is a component of an electricity supply system that divides an electrical power feed into subsidiary circuits, while providing a protective fuse or circuit breaker for each circuit in a common enclosure.
.
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This is not the time for wiki, this is the tine for the definitions in article 100.

What is the point?

The point is the rules are different for services than feeders or branch circuits.
 
That may have been a point somewhere - but it wasn't here. I was very surprised to find (prior to looking in Wiki) that there is no definition in the NEC for main distribution panelboard. In fact, I don't find a definition for distribution panelboard. If you look it up in the index, the index refers you to panelboards, which is defined in article 100 as .... you can look it up yourself. This is contrasted to switchboard. Nothing about either discusses the service entrance - which of course could be in another location for a variety of reasons.
 
dema said:
That may have been a point somewhere - but it wasn't here. I was very surprised to find (prior to looking in Wiki) that there is no definition in the NEC for main distribution panelboard. In fact, I don't find a definition for distribution panelboard. If you look it up in the index, the index refers you to panelboards, which is defined in article 100 as .... you can look it up yourself. This is contrasted to switchboard. Nothing about either discusses the service entrance - which of course could be in another location for a variety of reasons.
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Yes, there is no definition for those items as they are either panelboards, switchboards, or switchgear. Their exact function is not important to the application of the rules found in the NEC.

You would look to Article 230 for the service disconnect and the service disconnect(s) can be in any one of those items, as well as other types of equipment.
 
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