Mike Raiford wrote:
> Invisible wrote:
>> scott wrote:
>>>> (Woah - 63A? o_O Anybody know what thickness of copper it takes to 
>>>> handle that kind of currentl? That's gotta be more like a girder 
>>>> than a wire!)
>>>
>>> Roughly double your standard 13A cable would do...  Look at the cable 
>>> going to the starter motor on your car, that's usually 100A or so.
>>
>> 1. A car runs on 12V electrics, not 250V. Does that make a difference?
>>
>> 2. Is maximum load proportional to diameter or cross section area? 
>> (The latter is quadratically propertional to diameter.)
> 
> Hmmm... Here's some info:
> 
> http://www.powerstream.com/Wire_Size.htm
> http://www.epanorama.net/documents/wiring/wire_resistance.html
> 
> According to the one site, 6 AWG wire would be enough. Next size up if 
> over 100 ft. :)

I'd say 3 AWG - but either way, it's less than 1 cm thick.

Like I said, when they hook up the external generator, it comes with a 
cable well over 10 cm thick (!)

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Tom Austin wrote:
> Invisible wrote:
>> Apparently the planners have access to an A0 printer. I don't even 
>> want to imagine what that must cost... ;-)
> 
> 
> They are not too bad - at least the cheaper ones.  We have a 'plotter' 
> that prints 2'x3' pretty easily.  The paper is on a roll that is 3' wide 
> and like 50' long.

I used to own an old HP line plotter. (Do they still make those?) It 
seems amazingly fast - until you actually try to plot anything of any 
real complexity, and then suddenly it seems absurdly slow...

> If you need to get it printed look at local copy centers - they might be 
> able to help.  Some engineering shops (that sell stuff) might be able to 
> help you out as well.

Nah. If I was that bothered, I'm sure the planners themselves can supply 
a printout. (Indeed, it seems to be easy to get prints, and 
near-impossible to get electronic copies...)

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Invisible <voi### [at] devnull> wrote:
> I'd say 3 AWG - but either way, it's less than 1 cm thick.
>
> Like I said, when they hook up the external generator, it comes with a
> cable well over 10 cm thick (!)

A lot of that thickness will be insulation, shielding and armor.

Stephen

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Stephen wrote:
> Invisible <voi### [at] devnull> wrote:
>> I'd say 3 AWG - but either way, it's less than 1 cm thick.
>>
>> Like I said, when they hook up the external generator, it comes with a
>> cable well over 10 cm thick (!)
> 
> A lot of that thickness will be insulation, shielding and armor.

Probably.

The plug is physically larger than my head. The whole contraption looks 
like a giant's plaything has fallen out of the sky or something...

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And lo on Fri, 09 Nov 2007 11:44:37 -0000, Invisible <voi### [at] devnull> did  
spake, saying:

> Since we store stuff that has to be kept frozen, a power cut is a fairly  
> major event. Our customers won't be too pleased if their $80 million  
> project has to be restarted from scratch because the stuff melted! So in  
> the event of a power cut, a big truck comes along and dumps a huge lump  
> of pig iron labelled "CAT POWER" outside our building, with a  
> ridiculously huge cable and a comically over-sized plug on the end.  
> (Seriously, the cable is thicker than some tree trunks!)

And what happens if the firm can't get you a CAT out in time? If it's that  
crucial shouldn't you at least have a CAT UPS or equivalent to tide you  
over.

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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Invisible <voi### [at] devnull> wrote:
> Stephen wrote:
> > Invisible <voi### [at] devnull> wrote:
> >> I'd say 3 AWG - but either way, it's less than 1 cm thick.
> >>
> >> Like I said, when they hook up the external generator, it comes with a
> >> cable well over 10 cm thick (!)
> >
> > A lot of that thickness will be insulation, shielding and armor.
>
> Probably.

Not probably but defiantly.

> The plug is physically larger than my head. The whole contraption looks
> like a giant's plaything has fallen out of the sky or something...

Yip and the reverse is true. In the old days, people who worked on high power
equipment thought that electronic connectors looked like toy stuff.

Stephen

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Phil Cook wrote:
> And lo on Fri, 09 Nov 2007 11:44:37 -0000, Invisible <voi### [at] devnull> did 
> spake, saying:
> 
>> Since we store stuff that has to be kept frozen, a power cut is a 
>> fairly major event. Our customers won't be too pleased if their $80 
>> million project has to be restarted from scratch because the stuff 
>> melted! So in the event of a power cut, a big truck comes along and 
>> dumps a huge lump of pig iron labelled "CAT POWER" outside our 
>> building, with a ridiculously huge cable and a comically over-sized 
>> plug on the end. (Seriously, the cable is thicker than some tree trunks!)
> 
> And what happens if the firm can't get you a CAT out in time? If it's 
> that crucial shouldn't you at least have a CAT UPS or equivalent to tide 
> you over.

The thing is:

1. The guys at CAT have a contractual obligation to arrive within X 
minutes of being called. If they fail to do this, they must pay us 
absurd amounts of money.

2. The freezers don't instantly heat up when the power is turned off. 
They have this thing called... thermal insulation. ;-) Not to mention 
the specific melting heat of water. (Do you have any idea how much ice 

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And lo on Fri, 09 Nov 2007 15:02:40 -0000, Invisible <voi### [at] devnull> did  
spake, saying:

> Phil Cook wrote:
>> And lo on Fri, 09 Nov 2007 11:44:37 -0000, Invisible <voi### [at] devnull>  
>> did spake, saying:
>>
>>> Since we store stuff that has to be kept frozen, a power cut is a  
>>> fairly major event. Our customers won't be too pleased if their $80  
>>> million project has to be restarted from scratch because the stuff  
>>> melted! So in the event of a power cut, a big truck comes along and  
>>> dumps a huge lump of pig iron labelled "CAT POWER" outside our  
>>> building, with a ridiculously huge cable and a comically over-sized  
>>> plug on the end. (Seriously, the cable is thicker than some tree  
>>> trunks!)
>>  And what happens if the firm can't get you a CAT out in time? If it's  
>> that crucial shouldn't you at least have a CAT UPS or equivalent to  
>> tide you over.
>
> The thing is:
>
> 1. The guys at CAT have a contractual obligation to arrive within X  
> minutes of being called. If they fail to do this, they must pay us  
> absurd amounts of money.

Yeah, but that's little compensation if as a result businesses stop using  
you and you fold

> 2. The freezers don't instantly heat up when the power is turned off.  
> They have this thing called... thermal insulation. ;-) Not to mention  
> the specific melting heat of water. (Do you have any idea how much ice  


I'm just wondering as to the overall cost of a CAT UPS over the cost of  
the contract to bring in a CAT generator, which would also run all your  
electrical equipment.

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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Phil Cook wrote:
> And lo on Fri, 09 Nov 2007 15:02:40 -0000, Invisible <voi### [at] devnull> did 
> spake, saying:
> 
>> The thing is:
>>
>> 1. The guys at CAT have a contractual obligation to arrive within X 
>> minutes of being called. If they fail to do this, they must pay us 
>> absurd amounts of money.
> 
> Yeah, but that's little compensation if as a result businesses stop 
> using you and you fold

I don't think you understand what I mean by "absurd amounts of money". ;-)

[As in, like, if companies *did* stop using us, we'd *still* have so 
much money it wouldn't even matter...]

>> 2. The freezers don't instantly heat up when the power is turned off. 
>> They have this thing called... thermal insulation. ;-) Not to mention 
>> the specific melting heat of water. (Do you have any idea how much ice 

> 
> I'm just wondering as to the overall cost of a CAT UPS over the cost of 
> the contract to bring in a CAT generator, which would also run all your 
> electrical equipment.

Well, I'm sure somebody will have looked at that and decided it's not 
worth it. (I would think that for more than 3 seconds of cover, you'd 
need a battery larger than our entire office...)

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And lo on Fri, 09 Nov 2007 16:08:36 -0000, Invisible <voi### [at] devnull> did  
spake, saying:

> Phil Cook wrote:
>> And lo on Fri, 09 Nov 2007 15:02:40 -0000, Invisible <voi### [at] devnull>  
>> did spake, saying:
>>
>>> The thing is:
>>>
>>> 1. The guys at CAT have a contractual obligation to arrive within X  
>>> minutes of being called. If they fail to do this, they must pay us  
>>> absurd amounts of money.
>>  Yeah, but that's little compensation if as a result businesses stop  
>> using you and you fold
>
> I don't think you understand what I mean by "absurd amounts of money".  
> ;-)
>
> [As in, like, if companies *did* stop using us, we'd *still* have so  
> much money it wouldn't even matter...]

Sounds like you need a power cut, a narrow road, a tree, and a chainsaw.

>>> 2. The freezers don't instantly heat up when the power is turned off.  
>>> They have this thing called... thermal insulation. ;-) Not to mention  
>>> the specific melting heat of water. (Do you have any idea how much ice  

>>  I'm just wondering as to the overall cost of a CAT UPS over the cost  
>> of the contract to bring in a CAT generator, which would also run all  
>> your electrical equipment.
>
> Well, I'm sure somebody will have looked at that and decided it's not  
> worth it. (I would think that for more than 3 seconds of cover, you'd  
> need a battery larger than our entire office...)

You'd think.

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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