Service change question

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cowboyjwc said:
Point taken, but 100 to 200 sounds pretty resi to me.
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If you have much for "old downtown" businesses that are still the same thing they were 40-60 years ago, you probably have some 100 and even 60 amp single phase services still in use there.
 
shputnik said:
When changing a 100 amp to a 200 amp service does the utilities upgrade/ increase size of thier service drop conductors?

I have often seem contractors just tie the new 200 amp conductors to the existing wires
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Overhead? Every Utility I have worked for or dealt with has a "terms of service" that requires residential customers to notify the utility if they add 5kVA or more of load or some verbiage along those lines. So they rarely care what the main breaker says unless your submitting official notice of a load increase. Interesting aside (I have brought up here before) even under the NEC Triplex is not an NEC 310.104 "insulated" conductor. That's why they keep the definition of covered around so it can be used under the NEC.
Manufacturers supply instructions for sizing the ampacity. Most manufacturers use standard 'code words' for *plex cables and go by the Aluminum Association tables. Link to their PDF table

Check out Table 10 (of the pdf in the link) and the "Sun wind" Column. An EE can size triplex on the 'NEC side of a project' the same way under the NEC 310.15(C).
Around here in older resi neighborhoods with overhead power all that triplex ends up at a transformer with at best a "50" stamped on it, As in 50kVA. I have seen several houses attached to a 15kVA (As in 62.5A @ 240V). If 3 houses actually were pulling 160-200A off a 15kVA that might not last long enough for the wire to melt.
Another consideration besides cost is smaller wire limits the available fault current which in some states is limited to 10kAIC at the service point for residential (by Public Utility/Service Commission rules).
Cheers
 
in Colorado for Xcel Energy and the other 3 states they cover, #4 can handle 200Amps as overhead freer conductors:eek:hmy:. I was blown away when I did my last overhead service change and i double checked with them and they said it was completely sufficient. you can also check the "Southwire App" on your phone and plug in "Utility" not NEC and it will tell u apmacity allowable for them.
 
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