Maybe dumb it down a little? Info is being left out, maybe master electricians can fill in the gaps, but those of us just learning are left scratching our heads. Slow down, put in more info. Thank you.
What he is talking about here is an American 3 phase WYE system. In this system the three currents coming from the Active (Hot) wires when they return will sum to zero at the point where the three coils meet in the Transformer. If we attach a wire to this point we call this the Neutral wire. Note that this wire will still have Mains Voltage potential so the wire has to be Earthed (Grounded) via an Earth stake to make sure it is at Earth Potential ( 0 Volts).
You are showing a three phase service transformer. Three phase service is for industrial and commercial service. Industrial customers have large motors than benefit from three phase service. Residential service does not need three phase service because they only use single phase motors in their air conditioning. Residential only get single phase service and only use one single phase transformer connecting to a single phase wire and a neutral wire on the primary side of the transformer. The diagram of the three phase transformer is not required for this topic and the three phase Y transformer is in the substation and produces the typical distribution voltage of around 12,000 volts from the transmission lines.
@@kjellg6532 Why would you have 3-phase power? We have no residential three phase equipment to use three phase service. It is not until you get the commercial grade HVAC larger than 5 tons do you need three phase service. There are some apartment complexes that have three phase and supply the individual apartments with two of the three phase. These locations will have 208 v / 120 v instead of 240 v /120 v. Some utilities supply 208/120 single split phase to their customers. Most 240 v equipment will operate on 208 v. Three phase power adds an extra cost and complexity that is not economically appreciated unless large three phase motors are used.
@@TexasEngineer I have a 3-phase heating system, 20 kW. With water it weights about 350 kg. My son has a Tesla EV. It can be charged using 1 phase, 32A 7,4 kW or it can be charged with 3-phase 16A 11 kW. I have a carpenters saw, 3-phase. But I agree that most of our appliances runs on 1 phase 230V and it is a bit more practical as you have no balancing issues.
@@TexasEngineer Extra cost? It depends. Electrical loss pr kg copper is reduced. Price of drop wire to your house is decreased. In your main switch frame the incoming circuit breaker must be a 3-phase, i.e. more cost, but for all the 1-phase circuits the 2p breakers are the same. These are fed from a 3-phase rail system. One more rail, but less copper pr rail.
@@kjellg6532 I have a 19.2 kw air handler with electric heat strips. It pulls 82 amps on its 100 amp breaker. The strips only weight a pound or three. My main breaker is 150 amp and a normal gas house of my era have a 100 amp breaker. Your EV opens another issue I have not given any thought, mainly because it would require me and a lot of other people to make a major electrical panel upgrade and a large increase in the electric bill. Gasoline and cars are cheap in Texas and Texas has instituted a higher EV annual registration tax.
