Federal Pacific  Ventilated Transformers
 

Ventilated Single-Phase: 15 to 167 KVA
Three-Phase: 7.5 to 1000 KVA


The Type FH Line of ventilated dry-type transformers incorporates wire and/or strip wound coils in a barrel wound configuration. Horizontal and vertical spacers are strategically positioned in the windings to brace the winding layers and allow maximum ventilation. The electrical grade core steel is arranged in a construction designed to accommodate the coils.

Vibration Dampening System
The core and coil assemble is anchored to the enclosure through a vibration dampening system to reduce noise levels. Units through 600 KVA are provided with neoprene isolating pads while larger units are furnished with three layer rubber and cork pads. A flexible grounding conductor is installed between the core and coil assembly and the transformer enclosure.

Rugged Enclosure
Enclosures are rigidly braced and covers are fastened with slotted hex head screws for case of removal. A rugged steel base provides safe handling with a forklift.

Wiring Compartments
Front accessible wiring compartments are approved for 60 degree – 75 degree C cable. Terminals are sized to carry the full current capacity of the transformers.

UL Listed 220 Degree C Insulation System
To attain UL listing, it was necessary to complete an accelerated aging test as specified by Underwriters Laboratories, Inc. This insulation system was subjected to a series of exposures to heat, vibration, moisture, and dielectric tests. As a proven system this insulation system has received from Underwriters Laboratories, Inc. a recognized 220 degree C continuous rating. This total temperature of 220 degree C is derived from the average conductor temperature rise of 150 degree C, hotspot temperature gradient of 30 degree C, and an ambient temperature of 40 degree C.

The major components that allow for this 220 degree C rating are Nomex paper, resin-glass laminates, silicon rubber, and polyester varnish. This combination of materials and the care taken in construction and workmanship, not only give FH transformers a long operating life, but helps insure their quiet operation.

Versatile Performance
The design features Type FH family of UL Listed transformers assure versatile, economical, and reliable distribution of power. All transformers are fully tested to insure trouble-free installation and operation. The unique combination of ratings makes the FH family suitable for a wide variety of applications.

SELECTION AND APPLICATION CONSIDERATIONS

Selection Steps
* Determine the system supply voltage available (primary voltage).

* Determine the required load voltage rating (secondary voltage).

* Determine the KVA rating of the load. The KVA capacity of the transformer must equal or be greater than the load rating.

* Select a transformer model from the listings on the following pages.

Connections
Many single-phase transformers are provided with a serried multiple winding construction and a dual voltage primary or secondary identification (i.e 240 x 480 to 120/240). These transformers will have two windings on the primary or secondary that can be connected either in series for the higher voltage or in parallel for the lower voltage. Transformers with voltage ratings containing an “x” can only be connected for one or the other of the two voltages. On those unites with voltage ratings separated by a “slant”, the windings can be connected to provide either or both voltages (three wire operation).

Three-phase transformers are provided with a delta primary for three wire input and either a wye secondary for four wire output or a delta secondary for three wire output. Transformers with 240 volt delta single-phase lighting tap as a standard feature. Maximum single-phase 120 volt load should not exceed 10% of the three-phase KVA rating. The load should also be balanced at 5% maximum between terminals X2 to X4 and 5% between terminals X2 to X4. The three-phase KVA must also be reduced by 30% of the nameplate rating. For example, a 45 KVA transformer can have a 4.5 KVA maximum single-phase, 120 volt load. Of that 4.5 KVA, 2.25 KVA must be loaded between X1 – X4 and 2.25 KVA must be loaded between X2 – X4. The three-phase KVA rating must be reduced to 31.5 KVA.

Primary Tips
Three-phase transformers and most single-phase models are provided with taps in the primary winding to compensate for input voltage variations. The taps will provide a range of voltage adjustment above and/or below the nominal voltage rating of the transformer. The available quantity, location, and percentage of the tap connections are shown in the transformer listings. All transformers are furnished with a nameplate showing the terminal and tap arrangements.

Sound Levels
A humming sound is an inherent characteristic of transformers due to the vibration caused by alternating flux in the magnetic core. Sound levels will vary according to transformer size. Attention to installation methods can help reduce any objectionable noise. When possible, locate the transformer in an area where the ambient sound will be equal to or greater than the transformer sound level. Avoid locating units in corners. Make connections with flexible conduits and couplings to prevent transmitting vibration to other equipment. Larger units should be installed on flexible mountings to isolate the transformer from the building structure.

Transformers are designed, built, and comply with NEMA maximum sound level requirements as measured in accordance with NEMA ST-20.

Temperature
Insulation system limiting temperatures for FH Style dry-type transformers are classified by industry standards based on a 40 degree C ambient, 25 degree C ambient for FB styles.

Altitude
Standard self-cooled dry-type transformers are designed for operation with normal temperature rise at altitudes up to 3300 ft. above sea level. The transformer rated KVA should be reduced by 0.3% for each 330 ft. the transformer is installed about 3300 ft.

Polarity
Transformer polarity is an indication for the direction of current flow through the high voltage terminals with respect to the direction of current flow through the low voltage terminals at any given instant in the alternating cycle. Primary and secondary terminals are said to have the same (or additive) polarity when, at a given instant, the current enters the primary terminal in question and leaves the secondary terminal in question in the same direction as though the two terminals formed a continuous circuit. Single-phase transformers rated 600 volts and below normally have additive polarity. The polarity of a three-phase transformer is fixed by the internal connections between phases. It is usually designated by means of a vector diagram showing the angular displacement of the windings and a sketch showing the markings of the terminals.

Angular Displacement
The angular displacement of a three-phase transformer is the time angle expressed in degrees between the line-to-neutral voltage of a specified high voltage terminal and the line-to-neutral voltage of a specified low voltage terminal. The angular displacement between the high voltage and low voltage terminal voltages of three-phase transformers with delta-delta connections is zero degrees. The angular displacement for three-phase transformers with delta-wye connections is 30 degrees with the low voltage lagging the high voltage.

Parallel Operation
Transformers with the same KVA ratings can be connected in parallel if required conditions are met. Single-phase transformers must have the same voltage rating, tap settings and frequency rating. Plus, the impedance values of the transformers must be within 7.5% of each other. When paralleling three-phase transformers, the same conditions would apply and, in addition, the angular displacement of the transformers must be the same.

Transformer Banking
Three single-phase transformers can be properly connected to supply a three-phase load. The single-phase units can be used in a three-phase bank with delta connected primary and wye or delta connected secondary. The equivalent three-phase capacity would be three times the nameplate rating of each single-phase transformer. For example, three 15 KVA single-phase transformers will when properly banked, accommodate a 45 KVA three-phase load.

Balanced Loading
Single-phase loads connected to the secondary of a transformer must be distributed so as not to overloads any one winding of the transformer. Single-phase transformers generally have two winding secondaries that can be connected for 120/240 volt three wire operation. When so arranged, care must be taken when connecting 120 volt loads to assure that the total connected load on each secondary winding does not exceed one-half the nameplate KVA rating. When connecting single-phase loads on a three-phase transformer, each phase must be considered as a single-phase transformer. The single-phase loading on each phase of the three-phase transformer must not exceed one-third of the nameplate KVA rating. For example, a 45 KVA three-phase transformer with a 208Y/120 Volt secondary should not have any 120 volt single-phase loads distributed such that more than 15 KVA of single-phase load is applied to any one phase.

Transformer Protection
(Reference N.E.C. Article 450)

Transformers – 600 Volts or Less Primary Protection Only
If secondary protection is not provided, a transformer must be protected by an individual overcurrent device on the primary side. The primary overcurrent device must be rated: No more than 125% of the rated primary current or the next higher standard device rating (for primary currents of 9 amperes of more); no more than 167% of the rated primary current (for 2 amperes to 9 amperes); and no more than 300% of the rated primary current (for ratings less than 2 amperes). An individual transformer primary protective device is not necessary where the primary circuit overcurrent protective device provides the required protection.

Primary & Secondary Protection
If the transformer secondary is protected by an overcurrent protective device rated no more than 125% of the transformer rated secondary current (or the next higher standard rating device), an individual primary protective device is not required provided the primary feeder circuit overcurrent device is rated no more than 250% of the transformer rated primary current.

SELECTION CHARTS

SINGLE-PHASE TYPE FH: 150 DEGREES C RISE-220 DEGREES C INSULATION SYSTEM
INDOOR VENTILATED-FLOOR MOUNTED

240 X 480-120/240 VOLTS, 60 Hz

 600-120/240 VOLTS, 60 Hz ELECTROSTATICALLY SHIELED

SINGLE PHASE OPTIONAL TEMPERATURE RISE
TYPE FH: 115 DEGREES C AND 80 DEGREES INSULATION SYSTEM-INDOOR VENTILATED
FLOOR MOUNTED

115 DEGREES C RISE, 240 X 480 -120/240 VOLTS, 60Hz

80 DEGREES C RISE, 240 X 480 -120/240 VOLTS, 60Hz

THREE PHASE GENERAL PURPOSE
SINGLE-PHASE TYPE FH: 150 DEGREES C RISE-220 DEGREES C INSULATION SYSTEM
INDOOR VENTILATED-FLOOR MOUNTED

208-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED

208-480Y/277 VOLTS, 60Hz,

240-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED

480-208Y/120 VOLTS, 60Hz

480-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED

480-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED, COPPER

480-240/120 VOLTS, LT (LIGHTING TAP)60Hz

480-240/120 VOLTS, LT (LIGHTING TAP)60Hz, ELECTROSTATICALLY SHIELDED

480-480Y/277 VOLTS, 60Hz

600-208Y/120 VOLTS, 60Hz,  ELECTROSTATICALLY SHIELDED 

THREE-PHASE OPTIONAL TEMPERATURE RISE

208-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED

208-480Y/277 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED

240-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED

480-208Y/120 VOLTS, 60Hz, ALUMINUM

480-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED

480-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED, COPPER

480-240/120 VOLTS, LT (LIGHTING TAP)60Hz

480-240/120 VOLTS, LT (LIGHTING TAP)60Hz, ELECTROSTATICALLY SHIELDED

480-480Y/277 VOLTS, 60Hz

600-208Y/120 VOLTS, 60Hz,  ELECTROSTATICALLY SHIELDED,

THREE-PHASE OPTIONAL TEMPERATURE RISE
TYPE FH: 80 DEGREES C RISE-220 DEGREES C INSULATION-INDOOR VENTILATED
FLOOR MOUNTED

208-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED

208-480Y/277 VOLTS, 60Hz

240-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED

480-208Y/120 VOLTS, 60Hz

480-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED

480-208Y/120 VOLTS, 60Hz, ELECTROSTATICALLY SHIELDED, COPPER

480-240/120 VOLTS, LT (LIGHTING TAP)60Hz

480-240/120 VOLTS, LT (LIGHTING TAP)60Hz, ELECTROSTATICALLY SHIELDED

480-480Y/277 VOLTS, 60Hz

600-208Y/120 VOLTS, 60Hz,  ELECTROSTATICALLY SHIELDED

• Federal Pacific Industrial Control Transformers
• Federal Pacific Type FB Encapsulated Transformers
• Federal Pacific Type FH Ventilated Transformers
• Federal Pacific High Voltage General Purpose Transformers
• Federal Pacific Motor Drive Isolation Transformers
• Federal Pacific Unit Substation Transformers
• Federal Pacific VPI  Epoxy Shielded Transformers
• Federal Pacific K-Factor 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.