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what does "122-40 single phase service coming in from the transformer" mean??

what does "122-40 single phase service coming in from the transformer" mean??

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  #1  
Old 07-25-05, 07:52 PM
lross
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Smile what does "122-40 single phase service coming in from the transformer" mean??

Can anyone tell me what "you have a 122-40 single phase service coming in from the transformer" mean?? I have a rock solid wonderful home that was custome built in the 60s. The copper wiring has never been upgraded and I only have 3-prong grounded outlets in my kitchen. I will need to replace my air conditioner soon and I'd like to add a hot tub in my atrium. I'm afraid to do either because I don't think the electrical system as it stands is sufficient to do what I want. I would be very appreciative if one of you electrical geniuses could advise me because I am on a budget like most others and have been ripped off a few times (gotta be the hair! grin...)
HELP, please. THANKS.
 
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  #2  
Old 07-25-05, 08:07 PM
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What are you quoting?
 
  #3  
Old 07-25-05, 08:16 PM
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I am with John....what are you refering to and where did you get those numbers?

In general terms we look at current panel size and design to determine if you are able to add what you would like and not so much concerned with the transformer issues that is in control of the power company.

What size panel do you have with this 1960's house?......should be on the service panel itself.
 
  #4  
Old 07-25-05, 08:38 PM
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You'll have to ask the person who quoted that number to you. It means nothing to us.
 
  #5  
Old 07-26-05, 01:22 AM
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Originally Posted by lross
Can anyone tell me what "you have a 122-40 single phase service coming in from the transformer" mean??
Not me.

My guess.
one 220 volt single phase service coming from the transformer.
40 breaker capacity inside the main panel ????
 
  #6  
Old 07-26-05, 04:24 AM
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I think your mystery numbers may be referring to "120/240 volt supply".
 
  #7  
Old 07-26-05, 09:48 AM
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You'r basic question is the ampacity of the Service Conductors that terminate on the "Line" side of the Service Dis-Connect, or "Main", inside the Service panel.The current-rating of "Main", which is equivalent to the ampacity of the Service Conductors, should be indicated on the exterior surface of the device when you look at the panel. The device should also indicate an "On/Off" position, and should be identified as "Main"/ "Service Disconnect"

Please investigate this, and submit a "report".

Good Luck & Enjoy the Experience!!!!!!!!!!
 
  #8  
Old 07-26-05, 01:33 PM
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hmmm


you have a 122-40 single phase service coming in from the transformer
Not sure I want to assume they are asking 120/240 from that statement.....but hey......
 
  #9  
Old 07-26-05, 02:18 PM
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Read it aloud: one twenty two fourty volt service. To us, it means 120/240, but could easily be understood as 122-40. Still the amperage is missing from the original post.
 
  #10  
Old 07-27-05, 06:13 AM
WFO
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Utility generators generate 3 phase voltage. Without doing a lot of history here on Nicoli Tesla (who basically invented our 3 phase system) it means you have three hot wires that peak 120 degrees apart electrically. This is what you see on an electrical distribution system when you look up there and see 4 wires on the pole; 3 hot phases and one neutral.
Typically 3 phase is used on commercial and industrial applications. 99.99% of all residential services use single phase.

Single phase means simply that the utility is only using one of the phases of the line. It feeds into a transformer, which steps the voltage down to a usable value. If you look at the low side (small terminals) of the transformer, you see 3 lugs. The transformer winding has 240 volts across the two outside lugs. The center terminal is center-tapped internally so that either of the legs to the middle tap is 120 volts. (i.e.-120/240 volts). The center tap is grounded, so you get 120 from either leg to ground.

Sooooo.......single phase (one leg from the distribution system), 3 wire (the number of wires coming to your house from the transformer) 120/240 (the voltage available to you for utilization).

Let me quote myself before being corrected....
"Single phase means simply that the utility is only using one of the phases of the line"

I'm keeping it simple here. We can discuss 4w delta lighting legs and network connections some other time.
 
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