upchuckduck
Member
what single-phase and, three-phase is?
Can anyone explain to me..
- Thread starterupchuckduck
- Start date
Booth wiki knows 3Ø - ControlBooth
JD
Well-Known Member
More efficient way to move power.
More efficient way to run motors.
Three hots and a neutral as compared to one or two (Usually.)
Costs a lot more money for equipment so not usually found in homes.
Beyond that, things get very complicated. There are many variations on how the power is delivered and used. The two most common are Wye and Delta. When we think of three phase power and dimmer racks, we are usually thinking of Wye power being delivered on three legs, each about 120 volts to neutral, and each hot leg having a voltage potential of 208 to another hot leg. Voltages vary a bit from venue to venue, location to location. It is wise to know that this is not the only configuration or voltage scheme around.
More efficient way to run motors.
Three hots and a neutral as compared to one or two (Usually.)
Costs a lot more money for equipment so not usually found in homes.
Beyond that, things get very complicated. There are many variations on how the power is delivered and used. The two most common are Wye and Delta. When we think of three phase power and dimmer racks, we are usually thinking of Wye power being delivered on three legs, each about 120 volts to neutral, and each hot leg having a voltage potential of 208 to another hot leg. Voltages vary a bit from venue to venue, location to location. It is wise to know that this is not the only configuration or voltage scheme around.
Sony
Active Member
I thought three phase equipment itself always cost less...because it's simpler to make. For instance a 3 phase motor does not require a starter cap like a single phase motor does and it basically works exactly the same way as the generator at the power plant except in reverse. Also DC for electronics is much more easily derived from three phase with less filtering then single phase which is why electronics that run off three phase (think computers in a datacenter) are usually more electrically efficient than single phase electronics.
If I recall correctly the reason it's not found in homes is the increased cost and complexity in wiring it. Imagine every one of your outlets having 5 wires instead of 3 as well as having almost twice as much copper. Installing single phase is cheaper which is advantageous in a residential setting. However in a commercial setting with heavy power use the savings in power usage and equipment costs outweighs the cost of installation.
Some newer homes up north do have 3 phase power installed. Just because you have 3phase you can pull single phase off of it. This is done in many commercial offices where the only thing that actually uses 3phase is the air conditioner. I would love it if I had 3phase at the house. 3 phase is more efficient due to you are splitting the load across 3 legs of power rather than 1 or 2. In higher voltage applications where you may have 480v your amperage drops way down so your wire size drops also. Thus saving money yet you do have to run an extra conductor typically. 3 phase motors use 4 wires, single phase uses 3 so there is some added wire cost. (motors do not require a neutral unless they are ran off of a single leg of power.) in terms of lighting world we run 3 phase to cut down our load. For example, I have 2 dimmers one single phase and one 3 phase that each have a 100 amp load on them. The single phase the load is split across 2 hot legs since the load is divided 100/2 I am at 50a per leg. With the 3 phase dimmer with 100a/3 legs I am only pulling 33.33 amps per leg so I have cut down on my feeder wire awg.
