# Cat 300Kw stub up



## Forge Boyz (Nov 7, 2014)

Ok so I know this isn't answering the question, but a 300KW for a house? Why so big? 

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## Southeast Power (Jan 18, 2009)

We install this size generator all of the time.
typically the tank manufacturer has an access panel but, recently, we have had two of them that didn't have it.
We typically stub up the conduits a foot out of the slab and tape them up.
I don't like cementing fittings such as a coupling or an FA during the slab work.
The day the tank arrives we complete the conduit terminations.
Some can be end bells if the circuit breaker compartment has an open bottom, 
If the circuit breaker compartment has a solid bottom, you are going to want to use the FAs like you mentioned.
Bottom line,
CYA.
Plan on there not being an access panel and make them long enough to reach and terminate them as needed and, don't cement the fittings together until after you see the the tank and the generator.


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## Southeast Power (Jan 18, 2009)

This is a 500 kw. it had an 800 amp for the building and an 800 for the fire pump.
This is how we do them


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## Southeast Power (Jan 18, 2009)

I think this was a 450 with three breakers on the unit. 1- 4" with 600 copper, 1- 2" for one building, 1- 2" for a fire pump, 3-1" or 3/4" conduits for controls, and battery charger and jacket heater.

This is a 500 that has 6 per phase:








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## 460 Delta (May 9, 2018)

Forge Boyz said:


> Ok so I know this isn't answering the question, but a 300KW for a house? Why so big?
> Go big or go home?
> Sent from my SM-G970U using Tapatalk


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## oldsparky52 (Feb 25, 2020)

Do I have this math correct?

300kva/240V = 1,250 amps. 80%pf would be 1,000 amps at single phase 120/240.

300kva/(208*1.732) = 833 amps. 80%pf would be 666 amps at 3-phase 208/120.

That is some kind of house. How many gallons per hour does it consume?


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## Forge Boyz (Nov 7, 2014)

oldsparky52 said:


> Do I have this math correct?
> 
> 300kva/240V = 1,250 amps. 80%pf would be 1,000 amps at single phase 120/240.
> 
> ...


I would guess 6-9 GPH

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## oldsparky52 (Feb 25, 2020)

Forge Boyz said:


> I would guess 6-9 GPH
> 
> Sent from my SM-G970U using Tapatalk


So, $20+ per hour. Bigger than my budget, lol.


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## MikeFL (Apr 16, 2016)

I doubt it's going to operate @ 100%.


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## Forge Boyz (Nov 7, 2014)

I doubt it will operate at 10%

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## oldsparky52 (Feb 25, 2020)

Okay, to rephrase my question, how much does that burn idling?


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## SWDweller (Dec 9, 2020)

According to Cat, the C9 engine uses 8.7 gallons and hour @25% with fan 
100% load 21.3 per hour with the fan, 
Sure glad I do not have to feed that kitty. Unless you could find a dealer that would deliver off road fuel to you.


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## oldsparky52 (Feb 25, 2020)

Is this generator going to be available to the local PoCo for generation? 

How big is this house that it takes a 300kva generator?


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## ppsh (Jan 2, 2014)

oldsparky52 said:


> Is this generator going to be available to the local PoCo for generation?
> 
> How big is this house that it takes a 300kva generator?


Currently 2000sqft, a 8-10k sqft house is starting next year. Lots of irrigation for the equestrian side of the property too. Owner wants it done once and done right, he doesn't ever want to have to worry about maxing the generator out. Average draw on the 480v service doesn't really exceed 20-30a per leg during the day currently, but its nonstop building on the property. A bit overkill, but he has no issue with it getting loadbanked yearly.



Southeast Power said:


> We install this size generator all of the time.
> typically the tank manufacturer has an access panel but, recently, we have had two of them that didn't have it.
> We typically stub up the conduits a foot out of the slab and tape them up.
> I don't like cementing fittings such as a coupling or an FA during the slab work.
> ...


I believe this one will be lifted in place with the subbase tank attached. I'm planning on being there that day with materials on hand to do the flex connections if need be. Good point with the open bottom breaker enclosures, this is listed as having a rodent proof stub up area, so it may be an open bottom configuration.


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## oldsparky52 (Feb 25, 2020)

ppsh said:


> Currently 2000sqft, a 8-10k sqft house is starting next year. Lots of irrigation for the equestrian side of the property too. Owner wants it done once and done right, he doesn't ever want to have to worry about maxing the generator out. Average draw on the 480v service doesn't really exceed 20-30a per leg during the day currently, but its nonstop building on the property. A bit overkill, but he has no issue with it getting loadbanked yearly.


Lucky you to have a customer that doesn't mind spending money.  I hope you get to charge large.


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## Southeast Power (Jan 18, 2009)

That's not a good design with so little load on the generator.
I think they should have paralleled two 125s.


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## Southeast Power (Jan 18, 2009)

Just a little advantage we picked up.
Use double 45s instead of 90s for anything underground.
This is a stub up for a utility transformer, we used double 45 under the SE rated ATS and just one 45 into the stub up area for the utility transformer. The conductors can be easily pushed or hand-pulled through the conduits.
The boxed out area on the left of the conduits are for the primary. They are going to cut open that 5" and install a sweep. On D-day, that transformer will be removed and a new transformer will be placed over them. That small 1" on the left is for the CT meter


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## ppsh (Jan 2, 2014)

Most complex underground layout of my career so far. Pipes in the ground, strings blown through and ready for pour at the end of the week. Wrestling 3" solo isn't exact easy. Really starting to question at what point it is no longer considered a side job.


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## SWDweller (Dec 9, 2020)

nice job definitely done by an electrician


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## micromind (Aug 11, 2007)

Nice work!

Looks like it'll be an easy pour, good formwork.


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## ppsh (Jan 2, 2014)

Going nicely so far, generator is about a month out still. Really impressed with these transfer switches so far, most compact mechanism I have ever seen, especially on the 600A. ABB / Zenith TruOne ZTG with CAT branding. Engineer specified 4 pole transfer switches. The service is 480/277wye, the 100a service has no neutral from the utility termination can, its just a meter main feeding a 75kva 480-240delta transformer, 600a service has a neutral from the utility, but unused, just feeding a 500kva 480-12kv delta padmount. As far as I can tell there's no reason to pull any neutrals?


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## ppsh (Jan 2, 2014)

Got the 100a service tied through the transfer switch, 600a ats wired and stubbed in the switchgear ready for intercept once the Polaris connectors come in. 

Generator is still 2-3 weeks out. DeWalt cable stripper and M18 cable cutter were amazing labor savers with the 500s. Wish the supply houses locally carried colored xhhw aluminum.

Never really thought I'd be doing side jobs of this scope, just realized I have had my jman card for one year now


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## wcord (Jan 23, 2011)

Dumb question.
Why did you use FAs and chase nipples on the transfer switch and TAs on the panel jb?


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## ppsh (Jan 2, 2014)

wcord said:


> Dumb question.
> Why did you use FAs and chase nipples on the transfer switch and TAs on the panel jb?


Had to use them on the 600a transfer switch because I slid the switch into place, don't feel like lifting it over a bunch of TAs. Also gave more wire bending room. Ended up going going with same setup on the other one because my stubs were about an inch short of being level with the 600.

Could have gone with PVC JBAs, but not a common stocked item in these parts. Big fan of a chase nipple when I'll be pulling out of a panel, especially at a bad angle. Never have to worry about the rope burning through.


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## micromind (Aug 11, 2007)

ppsh said:


> Had to use them on the 600a transfer switch because I slid the switch into place, don't feel like lifting it over a bunch of TAs. Also gave more wire bending room. Ended up going going with same setup on the other one because my stubs were about an inch short of being level with the 600.
> 
> Could have gone with PVC JBAs, but not a common stocked item in these parts. Big fan of a chase nipple when I'll be pulling out of a panel, especially at a bad angle. Never have to worry about the rope burning through.


I use FAs and chase nipples often, for the same reason. It's easy to slide something heavy over the FAs rather than lift it over MAs and usually mess at least one of them up.


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## wcord (Jan 23, 2011)

Wouldn't have thought of that. Great idea


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## ppsh (Jan 2, 2014)

Got a shutdown today and intercepted the 600a side today. Working with the existing 350s made me remember why I decided to use aluminum.


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