Apartmt service-Delta

[Toros]

Hi,
i am revising the design;
Decided to go with 1200A, 3ph. service @ 120/240V, 4W;
Because: I heard that appliances in dwellings do not work properly @ 208v
Deal or no deal??

Thank you

 

[curt swartz]

You need to higher a qualified engineer. You are WAY over your head.

I doubt the utility would even give you a 1200 amp Delta service for a multi-family dwelling. Even if they will, the only use would if you had an elevator connected to the house panel. Otherwise the stinger leg is useless. The stinger leg would not be connected to the any of the apartment meters. 208/120 is the normal for larger multi-family services. If there are electric ranges or dryers there will be a slight reduction in "heat" but not a big deal.

BTW: You have at least 3 different threads going to the same subject. You need to reply to your original post and not create new topic for every post.

 

[Toros]

You need to higher a qualified engineer. You are WAY over your head.

I doubt the utility would even give you a 1200 amp Delta service for a multi-family dwelling. Even if they will, the only use would if you had an elevator connected to the house panel. Otherwise the stinger leg is useless. The stinger leg would not be connected to the any of the apartment meters. 208/120 is the normal for larger multi-family services. If there are electric ranges or dryers there will be a slight reduction in "heat" but not a big deal.

BTW: You have at least 3 different threads going to the same subject. You need to reply to your original post and not create new topic for every post.

HIGH LEG IS ONLY FOR ELEVATOR (THEY ARE ALWAYS CONNECTED TO HSE)AND GARAGE EXHAUST FAN

 

[mbrooke]

HIGH LEG IS ONLY FOR ELEVATOR (THEY ARE ALWAYS CONNECTED TO HSE)AND GARAGE EXHAUST FAN

Two legs will carry WAY more load then the remaining one.


POCO transformer will have to be severally over sized to handle that. Or you will need a pole pig bank with one 167-200 kva and another one or two at 25kva. Very none standard.


Go with a 120/208Y service, and have 1/3 the apartments on a-b, 1/3 b-c, 1/3 c-a.


Appliances will work ok.

 

[gar]

190526-0810 EDT

A two transformer 3 phase supply is fairly common around here. It is a fairly flexible way to do distribution for both residential and commercial. I see many two transformer poles, and many 3 transformer poles.

In my neighborhood we have a 3 phase delta distribution with 3 wires, no neutral. At the substation it is probably a wye secondary. Within 1 block of me there are at least two wild leg transformers. One neighbor and I and two street lights share a single 50 kVA 240 V center tapped transformer.

.

 

[infinity]

Hi,
i am revising the design;
Decided to go with 1200A, 3ph. service @ 120/240V, 4W;
Because: I heard that appliances in dwellings do not work properly @ 208v
Deal or no deal??

Thank you

Appliances will work just fine at the lower voltage it's just that their output will be about 25% lower when operated at 208 volts. If you wanted the full rated output at 208 volts then it would need to be designed for that voltage, as Mbrooke pointed out in that other thread they may be hard to find or do not even exist. A quick internet search will show that many appliances are dual rated for 208 and 240 volts.

One thing is for certain you do not want a Delta servce.

 

[mbrooke]

190526-0810 EDT

A two transformer 3 phase supply is fairly common around here. It is a fairly flexible way to do distribution for both residential and commercial. I see many two transformer poles, and many 3 transformer poles.

In my neighborhood we have a 3 phase delta distribution with 3 wires, no neutral. At the substation it is probably a wye secondary. Within 1 block of me there are at least two wild leg transformers. One neighbor and I and two street lights share a single 50 kVA 240 V center tapped transformer.

.

Could be delta at the sub, a lot of old 2.4 and 4.8kv distribution systems were true ungrounded delta. It was seen as a way of increasing service continuity- no need to trip and reclose on a squirrel bridging an insulator.