THE 3 PHASE POWER
RESOURCE SITE

3 Phase Power Grain Dryer
3 phase power is used today for many applications ranging from the above grain dryer to saw mills, conveyer belt systems, refrigeration and air conditioning, etc.

3 Phase Contents
- 3 Phase Power Home
- 3 Phase Wiring
- 3 Phase Power Calculation
- 3 Phase Power Converter
- 3 Phase Converters
  * Rotary Phase Converters
  * Static Phase Converters
- 3 Phase Generators
- 3 Phase Transformers
  * 3 Phase Isolation Transformers
- 3 Phase Motors
- 3 Phase Electricity
- 3 Phase Power Loads
- 3 Phase Frequency
  * Frequency Converters
- 3 Phase Distribution
- 2 Phase Systems
- 1 Phase Loads on 3 Phase Power
- 3 Phase Loads on 1 Phase Power


3 phase power three phase power three phase electricity three phase generator 3 phase converter, rotary three phase

 

Powering 1 Phase Loads on 3 Phase Power

To Buy Phase Converters
We Recommend ACE Brand.
Call 1-800-967-7217
Web Link:  Phase Converters

1 Phase Loads on 3 Phase Power
Single-phase loads may be connected to a 3 phase system in two ways.  This can be done either by connecting across two live conductors (a phase-to-phase connection), or by connecting between a phase conductor and the system neutral, which is either connected to the center of the Y (star) secondary winding of the supply transformer, or is connected to the center one winding of a delta transformer (High leg Delta system). Single-phase loads should be distributed evenly between the phases of the 3 phase system for efficient use of the supply conductors and supply transformer.   Read below for more about connecting a 1 phase load to a 3 phase power supply line.

Splitting 3 Phase Power for 1 Phase Loads
The line-to-line voltage of a 3 phase system is √3 times the line to neutral voltage. Where the line-to-neutral voltage is a standard utilization voltage, (for example in a 240V / 415V system) individual single-phase utility customers or loads may each be connected to a different phase of the supply. Where the line-to-neutral voltage is not a common utilization voltage, for example in a 347 /600V system, single-phase loads must be supplied by individual step-down transformers.
industrial 3 phase transformer

In multiple-unit residential buildings in North America, lighting and convenience outlets can be connected line-to-neutral to give the 120V utilization voltage, and high-power loads such as cooking equipment, space heating, water heaters, or air conditioning can be connected across two phases to give 208V.  This practice is common enough that 208V single-phase equipment is readily available in North America.  Attempts to use the more common 120/240V equipment intended for three-wire single-phase distribution will likely result in poor performance since 240V heating equipment will only produce 75% of its rating when operated at 208V.

Where 3 phase at low voltage is otherwise in use, it may still be split out into single phase service cables through joints in the power supply network or it may be delivered to a master distribution breaker panel at the customer's premises. Connecting an electrical circuit from one phase to the neutral generally supplies the country's standard single phase voltage (120VAC or 230VAC) to the circuit.

The power transmission grid is organized so that each phase carries the same magnitude of current out of the major parts of the power transmission system. The currents returning from the customers' premises to the last supply transformer all share the neutral wire, but the 3 phase system ensures that the sum of the returning currents is approximately zero. The delta wiring of the primary side of that supply transformer means that no neutral is needed in the high voltage side of the network.

Wiring Phase-Phase
Wiring directly between two phases provides √3 or 173% of the single-phase voltage (208VAC in US; 400VAC in Europe) because the out-of-phase waveforms add to provide a higher peak voltage in the resulting waveform. Such connection is referred to as a line to line connection and is usually done with a two pole circuit breaker. This kind of connection is typically used for high power appliances, such as (in the US) a 2 kW, 208 volt baseboard heater.

3 phase power systems may or may not have a neutral wire. A neutral wire allows the 3 phase system to use a higher voltage while still supporting lower voltage single phase appliances. In high voltage distribution situations it is common not to have a neutral wire as the loads can simply be connected between phases (phase-phase connection).

3 Phase Loads
The most common class of 3 phase load is the 3 phase electric motor. A common 3 phase induction motor has a simple design, inherently high starting torque, and high efficiency. Such 3 phase motors are applied in industry for 3 phase pumps, fans, blowers, compressors, conveyor drives, and many other types of motor-driven equipment. A 3 phase motor is more compact and less costly than a 1-phase motor of the same voltage class and rating; also 1-phase AC motors above 10 HP (7.5 kW) are not as efficient and thus not usually manufactured.   Large air conditioning equipment (for example, most York air conditioning units above 2.5 tons (8.8 kW) cooling capacity) use 3 phase motors for reasons of economy and efficiency.  Read more about 3 phase power loads here.  

3 Phase Loads Run on 3 Phase Power Generated on 1 Phase Power
There are many places and instances where 1 phase power is the only type of power that is available, or where the power company wants to charge tens, or even hundreds of thousands of dollars to install and supply 3 phase power.  In this situation a quality 3 phase generating phase converter is the easy choice to be run on 1 phase to power 3 phase equipment of any type.  Quality 3 phase converters are super efficient and a a good choice for this use.  Click here to read more about powering 3 phase loads with 3 phase power generated from 1 phase power.

3 Phase Converters
Often the advantages of 3 phase motors, and other 3 phase equipment, make it smart and easily worthwhile to convert single-phase power to generate 3 phase. Small and large customers, such as residential, rural businesses, or farm properties may not have access to a 3 phase supply, or may not want to pay for the extra cost of a 3 phase service, but may still wish to use 3 phase equipment. Such 3 phase converters may also allow the frequency (see also frequency converters) to be varied allowing for different equipment frequency requirements (50Hz, 60Hz, 400Hz, etc.) and also for motor speed control (VFDs).  Some locomotives are driven by 3-phase motors with 3 phase converters converted from the incoming supply of either DC or 1 phase AC.   The two main types of 1 phase to 3 phase converters are Rotary Phase Converters and Static Phase Converters.  Click here to read more about 3 phase converters.

Continue And Read About Additional 3 Phase Power Details:

- 3 Phase Power Home
- 3 Phase Wiring
- 3 Phase Power Calculation
- 3 Phase Electricity
- 3 Phase Power Loads
- 3 Phase Power Converter
- 3 Phase Converters
  * Rotary Phase Converters
  * Static Phase Converters
- 3 Phase Generators
- 3 Phase Transformers
  * 3 Phase Isolation Transformers
- 3 Phase Motors
- 3 Phase Frequency
  * Frequency Converters
- 3 Phase Distribution
- 2 Phase Systems
- 1 Phase Loads on 3 Phase Power
- 3 Phase Loads on 1 Phase Power

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Smooth 3 Phase Power Wave Form (center)
Because of its smooth wave length properties, 3 phase electrical power is used across the U.S. and throughout the world.



3 Phase Transformer

3 Phase Substation Transformer
(above)
There are a variety of 3 phase transformer types and voltages, depending on your power needs.


3 Phase Power Saw

3 Phase Power Saw (above)
There are a whole variety of power equipment and power tools which require 3 phase power to run.


TEMCo 3 Phase Converter

3 Phase Converter
(above)
Some Types of Rotary Phase Converters will run on 1 phase power and generate 3 phase power to run other 3 phase equipment.


 
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