Acme Three Phase Transformers

Acme's product offers a full line of applications, from commercial general power distribution and high harmonic conditions to specific industrial motor drive/factory automation systems, to low voltage landscape lighting applications. All of Acme products are designed, constructed and rated in to meet or exceed the standards established UL, CSA CE, NEMA, ANSI and IEEE. Acme Electric Corporation was founded in 1917 in Cleveland, Ohio. Since that time, Acme has been a leader in supplying power conversion equipment to the electrical and electronic markets. Dry type distribution transformers have been a central part of the Acme product line for over sixty years.

Three Phase Transformers must have 3 coils or windings connected in the proper sequence in order to match the incoming power and therefore transform the power company voltage to the level of voltage needed while maintaining the proper phasing or polarity.

SELECTION CHARTS

GROUP XII
277/480 PRIMARY VOLTS-208/277 SECONDARY VOLTS-10,60Hz

GROUP A
208 DELTA PRIMARY VOLTS-480Y/277 SECONDARY VOLTS-30, 60 Hz

GROUP B
240 DELTA PRIMARY VOTLS-208Y/120 SECONDARY VOTLS-30,60 Hz

GROUP D
480 DELTA PRIMARY VOLTS-208Y/120 SECONDARY VOTS-MAY BE USED ON A 4 WIRE 480Y/277 VOLT SUPPLY-30,60HZ
 

GROUP DI
480 DELTA PRIMARY VOLTS-SHIELDED UNITS-208Y/120 SECONDARY VOLTS
MAY BE USED ON A 4 WIRE 480Y/277 VOLT SUPPLY -30,60Hz

GROUP GI
480 DELTA PRIMARY VOLTS-SHIELDED UNITS-240 DELTA/120 TAP SECONDARY VOLTS
MAY BE USED ON A 4 WIRE 480Y/277 VOLT SUPPLY-30, 60Hz

*Non-shielded Unit

GROUP G2
LOW NOISE (minus 3 db)
480 DELTA PRIMARY VOLTS-240 DELTA/120 TAP SECONDARY VOLTS
MAY BE USED ON A 4 WIRE 480Y/277 VOLT SUPPLY-30, 60Hz

GROUP H
NON-VENTILATED TRANSFORMERS
480 DELTA PRIMARY VOLTS-240 DELTA/120 TAP SECONDARY VOLTS
MAY BE USED ON A 4 WIRE 480Y/277 VOLT SUPPLY- 20, 69 Hz
 

GROUP 1
480 DELTA PRIMARY VOLTS-480Y/277 SECONDARY VOLTS
MAY BE USED ON A 4 WIRE 480Y/277 VOLT SUPPLY - 30, 60 Hz

GROUP J
600 DELTA PRIMARY VOLTS-208Y/120 SECONDARY VOLTS- 30, 60Hz

GROUP K
ENCAPSULATED TRANSFORMERS, 115 DEGREES C RISE
600 DELTA PRIMARY VOLTS-208Y/120 SECONDARY VOLTS-30, 60Hz

THREE PHASE LOADS

1. Determine electrical load
A. Voltage required by load.
B. Amperes or KVA required by load.
C. Frequency in Hz (cycles per second).
D. Verify load is designed to operate on three phase.
All the above information is standard data normally obtained from equipment nameplates or instruction manuals.
2. Determine supply voltage
A. Voltage of supply (source).
B. Frequency in Hz (cycles per second).
The frequency of the line supply and electrical load must be the same. A three phase transformer is selected which is designed to operate at this frequency having a primary (input) equal to the supply voltage and a secondary (output)
equal to the voltage required by the load.
3. If the load nameplate expresses a rating in KVA, a transformer can be directly selected from the charts. Choose from the group of transformers with primary and secondary voltages matching that which you have
just determined.
A. Select a transformer with a standard KVA capacity equal to or greater than that needed to operate the load.
B. Primary taps are available on most models to compensate for line voltage variations.
C. When load ratings are given only in amperes, tables 3 and 4 or the following formulas may be used to determine proper KVA size for the required transformer.
     (1) To determine three phase KVA when volts and amperes are known:

                                       Three Phase KVA =
                                        Volts x Amps x 1.73
                                                 1000

     (2) To determine Amperes when KVA and volts are known:

                                        Amps =
                                      3 Phase KVA x 1000
                                          Volts x 1.73
Three Phase Example
Question: Select a transformer to fulfill the following conditions. Load is a three phase
induction motor, 25 horsepower @ 240 volts, 60 Hz and a heater load of 4 kilowatts
@ 240 volts single phase. The supply voltage is 480Y/277, three phase, 4 wire.
Answer: Compute the KVA required. Motor—From table 4 the current is 68 amps.

                            240 volts x 68 amps x 1.73 = 28.2 KVA
                                             1000
(The KVA can also be obtained from table 4).

Heater — 4 KVA
A three phase transformer must be selected so that any one phase is not overloaded. Each phase should have the additional 4 KVA rating required by the heater even though the heater will operate on one phase only. So, the transformer should have a minimum KVA rating of 28.2 + 4 + 4 + 4 or 40.2 KVA. Refer to the appropriate selection chart. A 480 delta primary—240 delta secondary transformer may be used on a 4 wire, 480Y/277 volt supply. The fourth wire (neutral) is not connected to the transformer. To not overload the transformer, a 45 KVA transformer should be selected.
NOTE: Any two wires of the 240 volts, 3 phase developed by the secondary of the transformer may be used to supply the heater. Any 2 wires of a 3 phase system is single phase.
 

TABLE 3
FULL LOAD CURRENTS IN AMPERES-
THREE PHASE CIRCUITS

TABLE 4
FULL LOAD AMPERES
THREE PHASE A.C. MOTOR

When motor service factor is greater than 1, increase full
load amps proportionally. Example: If service factor is 1.15,
increase above amp values by 15%.

3 phase KVA= Volts x Amps x 1.73
                                  1000

NOTE: If motors are started more than once per hour, increase minimum transformer KVA by 20%. 
 

• ACME SINGLE PHASE TRANSFORMERS -
• ACME THREE PHASE TRANSFORMERS  -
• ACME HARMONIC MITIGATING TRANSFORMERS -
• ACME NON-LINEAR K-RATED TRANSFORMERS -
• ACME DRIVE ISOLATION TRANSFORMERS -
• ACME AC LINE REACTORS TRANSFORMERS-
• ACME ENCAPSULATED AC LINE REACTORS TRANSFORMERS-
• ACME INDUSTRIAL CONTROL TRANSFORMERS -
• ACME ENCAPSULATED INDUSTRIAL CONTROL TRANSFORMERS -
• ACME FINGER GUARD INDUSTRIAL CONTROL TRANSFORMERS -
• ACME LOW VOLTAGE LIGHTING TRANSFORMERS & POWER SUPPLIES -
• ACME BUCK BOOST TRANSFORMERS -
• ACME PANEL-TRAN ZONE POWER CENTERS TRANSFORMERS -
• ACME AIR CONDITIONING, REFRIGERATION & APPLIANCE TRANSFORMERS -
• ACME CONSTANT VOLTAGE REGULATORS & LINE POWER CONDITIONERS TRANSFORMERS -
• ACME DC POWER SUPPLIES TRANSFORMERS -

Power Transformer Information:

 Power Transformer Manufacturer

• ACME Transformers - With Acme Electric being in business over 80 years, they have always believed in offering there customers superior service, quality and technical expertise in the transformer market.
• AMVECO Transformers - AMVECO designs and manufactures toroids transformers, current transformers, and auto transformers. Most AMVECO products are custom designed utilizing their state-of-art proprietary CAD programs.  The AMVECO engineers can quickly generate designs in a matter of hours, if needed.
• Federal Pacific Transformers -  Federal Pacific is a division of Electro- Mechanical Corporation, a privately held, American owned company founded in 1958. Federal pacific offers dry-type transformers from .050 KVA through 10,000 KVA single and three phase, up to 34.5 KV, 150 KV BIL with UL approval through 15 KV.
• Marcus Transformer - Ever since they opened their doors for business a half a century ago, they have been a leader in innovative transformer design. As a family-owned company they are proud of the reputation they have earned for making quality-built transformers that deliver exceptional performance and savings.
• Hammond Transformers -  Hammond Manufacturing was founded in 1917 in Guelph, Ontario, Canada. In the last 3 decades it has expanded to the US and the international markets offering many types of power transformers. 
• TEMCo Transformers - TEMCo Transformer, a family-owned business which has been manufacturing and distributing electrical products since 1968. They focus on transformers that significantly reduce power consumption over 30 percent compared to competitive makes.
• GE Transformers - GE has been a key player in the energy industry for more than a century.  Since the installation of their first steam turbine in 1901. They have become number one provider of high-technology power generation and distribution equipment.
• Jefferson Electric Transformers - Jefferson Electric has been a pioneer and innovator of magnetic products since 1915. Jefferson broad line of dry-type transformers are backed by quality assurance systems so stringent that each and every unit gets thoroughly tested before it goes out there door.
• More power transformer brands - Check out more companies by clinking this link.

 Power Transformer Types

• Distribution Transformers - Distribution transformers are generally used in electrical power distribution and transmission power. This class of transformer has the highest power, or volt-ampere ratings. and the highest continuous  voltage rating.
• Substation Transformers - Substation Transformers are large devices which usually weigh tens of thousands of pounds.   They are filled with tens of thousands of gallons of heat transfer fluid.  Although they are typically 99.8% efficient in the transforming of electricity from one voltage to another, processing hundreds of Mega Volts-Amps of electricity force the liberation of hundreds of BTUs per second.
• Medical Grade Isolation
   Transformer - Medical Grade Transformers generally refer to the transformers used in medical devices as well as hospital, biomedical and patient care equipment. There are a number of strict safety rules, guidelines and laws governing the design, construction and the test of these transformers.
• Drive Isolation Transformer - They are used to isolate a drive from a main power line to prevent the transmission of harmonics that the drives produce back into the power line.  They stop drive harmonics from disrupting computers and other sensitive equipment.
• Toroidal Transformers - Toroidal Transformers are more efficient than the cheaper laminated EI types of similar power level. Some of the advantages are smaller size, lower weight, less mechanical hum, (making them superior in audio amplifier), low-off-load loss.

 Power Transformer Types

• Step-Up Transformers - A Step-Up Transformer is one whose secondary voltage is greater than its primary voltage.  This kind of transformer "steps up" the voltage applied to it. -
• Step-Down Transformers - A Step-Down Transformer is  designed to reduce voltage from primary to secondary.  They can range from sizes from .05 KVA to 500 KVA
• Isolation Transformers - An Isolation Transformer is a device that transfers energy from the alternating current (AC) supply to an electrical or electronic load.  It isolates the windings to prevent transmitting certain types of harmonics.
• Buck Boost Transformers - Buck Boost Transformers make small adjustments to the incoming voltage. They are often used to change voltage from 208v to 240v for lighting applications.  Major advantages of Buck boost transformers include; low cost, compact size and light weight. 
• High Voltage Transformer - There are many different types of voltage transformers. A High Voltage Transformer operates with high voltages. Typically, these voltage transformers are used in power transmission applications, where voltages are high enough to present a safety hazard.
• Medium Voltage Transformers - A Medium Voltage Transformer can be connected directly to a primary distribution circuit and generally has the most load diversity. These voltage transformers have installation practices that are generally in accordance with application recommendations from the Institute of Electrical and Electronic Engineers (IEEE).
• Low Voltage Transformers - A Low Voltage Transformer is an electrical device that transforms 120 volts (line voltage) into 12 volts or 24 volts (low voltage). Some uses for low voltage transformer are in landscaping lighting.
• Single Phase Transformers - In electrical engineering, single-phase electric power refers to the distribution of electric power using a system in which all the voltages of the supply vary in unison. Single-phase distribution is used when loads are mostly lighting and heating, with few large electric motors.
• Three Phase Transformers - Three Phase Transformers must have 3 coils or windings connected in the proper sequence in order to match the incoming power and therefore transform the power company voltage to the level of voltage needed while maintaining the proper phasing or polarity.
• Custom Transformers - Custom Transformers are designed for a certain performance specifications and size requirements.  The company works with your engineering specification. 
• Industrial Control Transformers - Industrial Control Transformers are used to convert the available supply voltage to the required voltage to supply industrial control circuits and motor control loads.
• Pad Mounted Transformers - Pad Mounted Transformers are usually single phase, or three phase, and used where safety is a main concern. Typical applications; restaurant, commercial building, shopping mall, institutional. 
• Pole Mounted Transformers - Pole Mounted Transformers are used for distribution in areas with overhead primary lines. Outside a typical house one can see one of these devices mounted on the top of an electrical pole.
• Oil Filled Transformers - Oil Filled Transformers are transformers that use insulating oil as insulating materials.  The oil helps cool the transformer. Because it also provides part of the electrical insulation between internal live parts, transformer oil must remain stable at high temperatures over an extended period.
• Dry Type Transformers - Dry-Type Transformers are available for voltages up through 34.5 kV (although the most common upper limit is 15) and KVA ratings up through 10,000 (with 5000 as the usual limit). Dry-type use air as a coolant, lowering health and environmentally concerns.
• Auto Transformers - An Autotransformer is an electrical transformer with only one winding. The winding has at least three electrical connection points called taps. Autotransformers are frequently used in power applications to interconnect systems operating at different voltage classes, for example 138 kV to 66 kV for transmission. Another application is in industry to adapt machinery built for 480 V supplies to operate on the local 600 V supply.
• More power transformer types - Read further about additional transformer types and their uses.

 Power Transformer Term Definitions

• Electrical Transformers - Electrical Transformers are devices used to raise or lower the voltage of alternating current. For instance, power is transported over long distance in high voltage power lines and then transformers lower the voltage so that the power can be used by a business or household.
• Isolating Transformers - An Isolating Transformer is a transformer, often with symmetrical windings, which is used to decouple two circuits.  An Isolation transformer allows an AC signal or power to be taken from one device and fed into another without electrically connecting the two circuits. Isolation transformers block transmission of DC signals from one circuit to the other, but allow AC signals to pass. 
• Transmission Power Lines - A Transmission Line is the material medium or structure that forms all or part of a path from one place to another for directing the transmission of energy, such as electromagnetic or acoustic waves as well as electric power transmission. Components of transmission lines include wires, coaxial cables,  dielectric slabs, option fibers, electric power lines, and waveguides.
• Transformer Voltage - The measure of the amount of force on a unit charge because of the surrounding charge.
• Transformer Phase - Most transformer are either single phase or three phase.
• Transformer Frequency - The transformer cannot change the frequency of the supply. If the supply is 60 hertz, the output will also be 60 hertz.
• Transformer K Factor - Some transformers are now being offered with a k-factor rating. This measure the transformer's ability to withstand the heating effects of non-sinusoidal harmonic currents produced by much of today's electronic equipment and certain electrical equipment.
• Primary Voltage - The coil winding that is directly connected to the input power.
• Secondary Voltage - The coil winding  supplying the output voltage.
• Harmonic Cancellation - Harmonic cancellation is performed with harmonic canceling transformers also known as phase-shifting transformers. A harmonic canceling transformer is a relatively new power quality product for mitigating harmonic problems in electrical distribution systems. This type of transformer has patented built-in electromagnetic technology designed to remove high neutral current and the most harmful harmonics from the 3rd through 21st.
• Weatherproof - Enclosed transformers come with a weatherproof standard set by NEMA.
• Epoxy Encapsulated - A process in which a transformer or one of its components is completely sealed with epoxy or a similar material. This process is normally preferred when a unit might encounter harsh environmental conditions.
• More power transformer terms - Such as inductor, ground fault, core saturation, current transformer, faraday shield, etc.

Related Transformer Products

• Voltage Regulators - A Voltage Regulator is an electrical regulator designed to automatically maintain a constant voltage level.  It may use an electromechanical mechanism, or passive or active electronic components. Depending on the design, it may be used to regulate one or more AC or DC voltages.
• AC Line Reactor - AC Line Reactors is a three phase transformer used in conjunction with AC variable frequency and DC motor drive. They are a bi-directional protective filtering device.
• Line Power Conditioners - Power or Line Conditioners regulate, filter, and suppress noise in AC power for sensitive computer and other solid state equipment.
• DC Power Supplies - Conversion of one form of electrical power to another desired form and voltage. This typically involves converting 120 or 240 volt AC supplied by a utility company to a well-regulated lower voltage DC for electronic devices.
• Rotary Phase Converters - Rotary Phase Converters are commonly used in home or small commercial or industrial settings. Rotary phase converters convert single-phase power into three-phase power. This is a very cost-effective way to power three-phase electric motors and other three phase equipment.
• Frequency Converters - A Frequency Changer or Frequency Converter is an electronic device that converts alternating current (AC) of one frequency to alternating current of another frequency.
• Voltage Converters - A Voltage Converter changes the voltage of an electrical power source and is usually combined with other components to create a power supply.
• Magnetic Motor Starters - Magnetic Motor Starters are essentially heavy duty relays mounted in boxes, often equipped with heater/thermal overloads matched to the motor they start.
• Motor Starting Auto Transformers - An Auto Transformer starter uses an auto transformer to reduce the voltage applied to a motor during start. The auto transformer may have a number of output taps and be set-up to provide a single stage starter, or a multistage starter.

For an additional resource the Best of Industry Web Directory : Electrical Power Transformer Directory section is quite useful.