Shaking Head Over Specifications

Status
Not open for further replies.
lol Mr Infinity, no i can't 'splain it & would probably throw it all in the trash along with the 110.3B it rode in on

~RJ~
 
winnie said:
IMHO this is the most sensible approach. If the customer has more money then sense, then take it and enjoy the profit.

If they care about money then it lets you submit a lower quote.

Though 'increase one wire gauge' doesn't quite mean what they think it means. Just because odd AWG sizes are uncommon doesn't mean one = 2.

Jon
Click to expand...
And because of low demand, the intermediate size may well cost a lot more than the larger bracketing size.
 
My guess is that this boilerplate spec has been around for decades and no one wants to pay to change it. The likelihood is is that the cost to change it will exceed what the extra cost is to just leave it alone.
 
That is the engineering design. The NEC gives the minimum requirements.
The engineering design specifications are good. Whats your problem ?
Do you know what an RFI is ?
If your doing a bid , qualify your bid as specified.
 
JEFF MILLAR said:
That is the engineering design. The NEC gives the minimum requirements.
The engineering design specifications are good. Whats your problem ?
Do you know what an RFI is ?
If your doing a bid , qualify your bid as specified.
Click to expand...
The spec is overkill and a big waste of money. Yes the electrician gets paid to install this nonsense but someone is paying the bill for this over design. A #8 hot leg with a #6 neutral for a 20 amp circuit, that's just plain dumb. And yes just about everyone here knows what an RFI is. :rolleyes:
 
drcampbell said:
The next time you wonder, "what horse's ass came up with this specification?" ...

Space Exploration History: The Space Shuttle and the Horse's Rear End

A funny story about the sizing of the Space Shuttle
astrodigital.org
Click to expand...
The fact that a specification from ancient history can affect space travel is interesting but is also logical and practical, we don't complain about those kind of specs.

We complain about specs like the one in the OP because they are foolish and wasteful. Such specifications also have the unfortunate by product of decreasing the credibility of engineers when they ought to be the most credible on the construction team.
 
infinity said:
The spec is overkill and a big waste of money. Yes the electrician gets paid to install this nonsense but someone is paying the bill for this over design. A #8 hot leg with a #6 neutral for a 20 amp circuit, that's just plain dumb. And yes just about everyone here knows what an RFI is. :rolleyes:
Click to expand...

Where are you seeing a #8 hot and #6 neutral for a 20A branch circuit?
 
Xptpcrewx said:
Where are you seeing a #8 hot and #6 neutral for a 20A branch circuit?
Click to expand...

They start 2 awg oversized for hot, 4 awg oversized for neutral and ground if you have 2 mwc in a single conduit. This then gets increased by 1 size (2 awg) for length > 100 feet.


You very quickly get to hugely oversized..

Jon
 
drcampbell said:
The next time you wonder, "what horse's ass came up with this specification?" ...

Space Exploration History: The Space Shuttle and the Horse's Rear End

A funny story about the sizing of the Space Shuttle
astrodigital.org
Click to expand...
This is off topic but goes along with this story.
Man to his wife..."Why do you always cut the ham in half before putting it in the pan to bake it?"
Wife - "That's the way my mother taught me, ask her why"
Man to MIL - "Why did you tell my wife to cut the ham in half before putting it in the pan to bake it?"
MIL - "That's the way my mother taught me, you'll have to ask her."
Man to wife's grandmother - "Why did you tell your daughter to cut the ham in half before putting it in the pan to bake it?"
Grandmother - "Because we never had a pan big enough!"
 
Little Bill said:
This is off topic but goes along with this story.
Man to his wife..."Why do you always cut the ham in half before putting it in the pan to bake it?"
Wife - "That's the way my mother taught me, ask her why"
Man to MIL - "Why did you tell my wife to cut the ham in half before putting it in the pan to bake it?"
MIL - "That's the way my mother taught me, you'll have to ask her."
Man to wife's grandmother - "Why did you tell your daughter to cut the ham in half before putting it in the pan to bake it?"
Grandmother - "Because we never had a pan big enough!"
Click to expand...
I thought the punch line was going to be ask the great grandmother but she's dead so the why is lost to time....
 
drcampbell said:
The next time you wonder, "what horse's ass came up with this specification?" ...
Click to expand...
Also, completely wrong. Granted that the first "plate ways" were set on existing roads, but there's no evidence that those predated the quarries where they were. Fast forward through lots of gauges and a bunch of people decided to use 1500mm between the heads of the rails; that was harder to measure so it became 1435mm between the inside edges. Convert 1435mm to inches? 56.49" (4' 8 1/2").
 
I've been on the other side of this and now and then. The place I used to work 30 years ago used to occasionally put up buildings and we had to write specs for those buildings. Rather than try to make them the cheapest possible solution for what we were doing, a lot of time there is some conservative design built into some of the things like wire sizing and conduit sizing because many times we didn't know exactly what we were going to actually need but had to come up with drawings and specifications well ahead of when we would know this kind of stuff. By the time the building was actually being built there was never any time to change the drawings to save a few hundred dollars on wire or conduit. It just wasn't worth the effort.

For instance the difference between the wiring for a 75 horsepower pump and 100 horsepower pump isn't that much cost-wise but you know damn well that if you put in 75 horsepower in the spec and size it for that and you have to change to 100 horsepower the electrical contractor will screw you every way they can when they make the change. It's just the way they make their profit. In fact many project managers used to get a bonus based on the amount of change orders they were able to generate. It's not as common as it used to be but it used to be pretty common.

If you think the thing is overengineered to the point where it is cost effective to change the spec and then have everybody rebid it to the new spec, maybe it is a good idea to point this out to the engineer. Sometimes people just don't realize how much boilerplate expenses are built into some of these specs. Keep in mind that many if not all of these kind of crazy things came about because some electrical contractor tried to cut corners to save money and so the engineer is just protecting himself.
 
infinity said:
EMT is technically tubing not conduit but in the context of this spec. EMT is fine. Not sure where the engineering came from but the client is a foreign bank so maybe this is from their boilerplate. Does anyone know what a network is in the context of this document?
Click to expand...
Thinking network = HR.?
 
Currently on the other side of this as a customer.

Just walked into our new lab space to see the installation work. 32 receptacle locations each with two duplex receptacles. The run from the panel to the furthest receptacle is about 180 feet.

It looks like all the receptacles will be fed with 3 circuits, and each circuit is getting its own 12-2 MC home run to the panel.

I hope nobody decides to plug a space heater in....

(Note: this was a case where there was no specification provided other than 'put 120V receptacles at these locations'. )

-Jon
 
winnie said:
Currently on the other side of this as a customer.

Just walked into our new lab space to see the installation work. 32 receptacle locations each with two duplex receptacles. The run from the panel to the furthest receptacle is about 180 feet.

It looks like all the receptacles will be fed with 3 circuits, and each circuit is getting its own 12-2 MC home run to the panel.

I hope nobody decides to plug a space heater in....

-Jon
Click to expand...
In my brief stint as a facility manager I had to deal with a number of lab relocates and reconfigurations. Because the equipment wasn't moved around much once it found a home, the load was fairly constant, but I had to hound the scientists for the information so we could balance the panels. I doubt I would have given the green light to so few circuits for so many locations.
 
Status
Not open for further replies.
Top