220v single phase-480 single phase

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chefiam1

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Centerville,pa
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retired 20yrs electrician
is it worth it to have a 110/220v single phase drop then adding a 220v-480v transformer and running it
900 feet. trying to get around the utilities they want 26,000 to drop 3 phase?i need to run a 20 h p pump
then tap off for general 11ov lights and plugs.

thanks,chef
 
chefiam1 said:
is it worth it to have a 110/220v single phase drop then adding a 220v-480v transformer and running it
900 feet. trying to get around the utilities they want 26,000 to drop 3 phase?i need to run a 20 h p pump
then tap off for general 11ov lights and plugs.

thanks,chef
Click to expand...
No it will not be worth it at that length. Aluminum conductors are much cheaper than transformers in this scenario.
 
chefiam1 said:
is it worth it to have a 110/220v single phase drop then adding a 220v-480v transformer and running it
900 feet. trying to get around the utilities they want 26,000 to drop 3 phase?i need to run a 20 h p pump
then tap off for general 11ov lights and plugs.

thanks,chef
Click to expand...
Ask PenPower for a 240/480 single phase service, you have to check the 'other' box on the application.
You can get a small transformer if you need a 120 load like a GFCI.
 
electrofelon said:
No it will not be worth it at that length. Aluminum conductors are much cheaper than transformers in this scenario.
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Well maybe. (and please correct me if I am wrong here)

900ft of 240v at 100A needs two sets of 350s. Assuming 900ft x 2 sets x 4 conductors (I didn't want to bother figuring the egc upsize for vd size increase so I left it fullsize) = 7200ft = just under $10K in wire for URD. Maybe I have too much wire and one of the EGC can go away if its all direct bury.

Running the 900ft at 600v with a pair of transformers is $1400 in wire and $3000 in transformers. Add another $1200 for fused disconnects, fuses, ground rods, etc. So say $5600 with transformers. Then consider the energy cost of transformer losses over the life of the installation. I don't know what that would be.
 
Todd0x1 said:
Well maybe. (and please correct me if I am wrong here)

900ft of 240v at 100A needs two sets of 350s. Assuming 900ft x 2 sets x 4 conductors (I didn't want to bother figuring the egc upsize for vd size increase so I left it fullsize) = 7200ft = just under $10K in wire for URD. Maybe I have too much wire and one of the EGC can go away if its all direct bury.

Running the 900ft at 600v with a pair of transformers is $1400 in wire and $3000 in transformers. Add another $1200 for fused disconnects, fuses, ground rods, etc. So say $5600 with transformers. Then consider the energy cost of transformer losses over the life of the installation. I don't know what that would be.
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URD consists of all 4 conductors, no? So for parallel 350s you need 1800’, not 7200. Or am I missing something?


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Not sure of the details, but can you run it as a service with a reduced neutral, no disconnect just a meter? Just did that for 800 feet for a PV system, ran 500/500/ 1-0 (custom order plexed USE) , $3.60 per foot. You may want two sets. That's only $6500 in wire. Maybe it would be less if you don't need that much wire, maybe one set of 750 or like you said two sets of 350.
 
chefiam1 said:
it's northwestern rural electric co op they do not drop 240/480v.tried that

thanks, chef
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I am a big fan for 240/480 single phase as a solution.
Push a little harder the more people that do the easier it is for all of us, I have sourced transformers for COOP's before.
Sometimes the COOP 'service planner' is too lazy to look and see that they can get one.
 
tortuga said:
I am a big fan for 240/480 single phase as a solution.
Push a little harder the more people that do the easier it is for all of us, I have sourced transformers for COOP's before.
Sometimes the COOP 'service planner' is too lazy to look and see that they can get one.
Click to expand...
COOP’a tend not to do specialized transformers because they have to keep a spare in the yard. Not cost effective. Up until the early 80’s, our EMC would not install pad mounts. They would use pole transformers in an enclosure on a slab. Their reasoning was that they would have to keep another one in the yard. Up until that time, all underground went to the pole, and up to pole mounts. Even residential.
 
retirede said:
URD consists of all 4 conductors, no? So for parallel 350s you need 1800’, not 7200. Or am I missing something?


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Click to expand...

URD comes in both single and multiconductor types. I was figuring based on single conductor URD type, going under the assumption that the included EGC in quad would be the wrong size since the conductors are vastly increased in size for voltage drop. It may be ok, I don't know.
 
tortuga said:
Yes in my area people whom run irrigation pivots can be miles from any three phase.
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Is this an application where a 3ph motor would be used with a VFD getting single phase input? Or is it just across the line starting a 20hp single phase motor?
 
Todd0x1 said:
Is this an application where a 3ph motor would be used with a VFD getting single phase input? Or is it just across the line starting a 20hp single phase motor?
Click to expand...
You can do it either way.
I have mostly been involved in supplying the service for the pump guys,
The COOP's are member run so it only takes one or two complaints to get them to offer it.
The pole pigs are readily available
search for a
GE/Prolec 25 kVA Pole Mount Transformer 12470 - 240/480, Single Phase
 
singlephasepowersolutions.com

The BELLE Motor ™

SPPS makes and sells the world's only true large horsepower single-phase electric motors. SPPS has secured an exclusive right to the proprietary and
singlephasepowersolutions.com singlephasepowersolutions.com
 
Todd0x1 said:
Running the 900ft at 600v with a pair of transformers is $1400 in wire and $3000 in transformers. Add another $1200 for fused disconnects, fuses, ground rods, etc. So say $5600 with transformers. Then consider the energy cost of transformer losses over the life of the installation. I don't know what that would be.
Click to expand...

I still don't think transformers are worth it, but even if it was I wouldn't stop at 600v, why not just go to 15kv....would just need 1 CN primary which is like $2/ft.
 
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