Medium voltage switchboard system from 1 to 36 kv sepam protection relays masterpact protection switchgear from 100 to 6300 a trihal mvlv dry cast resin transformer from 160 to 5000 kva evolis mv vacuum switchgear and components from 1 to 24 kv. Medium voltage fuses are not intended to provide overload protection in the same sense as fuses rated 600 volts or less. Low voltage current transformers for the usage in the isolated area of mv switchgear from page 38 0. Medium voltage switchgear application guide transformers.
Bartype current transformer this type of current transformer uses the actual cable or busbar of the main circuit as the primary winding, which is equivalent to a single turn. Medium voltage fuse current ratings do not have the same meanings as the ampere ratings of low voltage fuses. A mediumvoltage transformer is connected to the electrical feeding system using a. Mediumvoltage distribution voltage regulators type jfr. Medium voltage transformers metrix electronics ltd. They are intended to supply electrical measuring instruments, meters, relays or other electrical devices. The indoor dry type transformers are arranged to act as a support for the conductor in the primary circuit. Transformer inrush current, including the combined effects of transformer magnetizinginrush current and the energizinginrush currents associated with connected loadsparticularly following a momen. Wall bushing type transformer with short circuitable secondaries. Since the noise is a vibration or range of vibrations, the. The basic function is to change the magnitude but not the nature of primary voltage and current to secondary values to 120 volts and 5 or 1 amp where relays can be applied. Current transformers can be designed for measurement as well as for complex transient protection. Ratios on rated voltage connection and on tap extreme connections. Medium voltage transformers discover our range of drytype, oil and power transformers from medium voltage up to 170kv.
Current transformer basics and the current transformer. In mv electrical distribution, the high current and voltage values mean that they cannot be used directly by metering or protection units. Medium voltage distribution voltage regulators type jfr. Selection guide for transformer primary fuses in medium voltage industrial, commercial, and institutional power systems 4. Acme has engineered its transformers to minimize this problem. It employed in electrical energy power system for stepping down the voltage of the system to some protected value which is often provided to low rating meter. They may be configured for motor starting, transformer feeders, capacitor feeders, or future sp aces. For connection to the mediumvoltage grid, smasolartechnologyag recommends using an mv transformer with a tap changer on the highvoltage side to enable alignment to the voltage level of the utility grid. Selection guide for transformerprimary fuses in mediumvoltage industrial, commercial, and institutional power systems 4. The preferred location for the current transformers is the circuit breaker spouts. Polarity and phase relation on rated voltage connection. A power transformer is a static piece of equipment with two or more windings which, by electromagnetic induction, transforms a system of alternating voltage and current into another system of voltage and current usually of different values and at the same frequency for.
Transformers should transform the primary voltage to a new voltage, needed by the consumer that is, the secondary voltage level. Protection of single pole insulated voltage transformers against feroresonance phenom ena is stated in appendix 3. Mediumvoltage transformer all industrial manufacturers. Current transformers voltage transformers medium voltage distribution catalogue 2012 make the most of your energy. The technical guide these technical guides help you comply with installation standards and rules i. Medium voltage switchgear construction checklist page 1 of 6. Under normal operating conditions this sum is zero.
Medium voltage products current and voltage instrument. Interruption of small mediumvoltage transformer current with a vacuum circuit breaker. Pdf interruption of small mediumvoltage transformer. Our long experience with all types of distribution transformers translates into reliable products for any application, while our new trihal iot connected features allow you to take a step forward in efficiency. Medium voltage products technical guide protection criteria for medium voltage networks. The application of 600 volt class current transformers in. The current transformer type cn14c without primary conductor, installation in sf6 gis, indoor or outdoor.
Lowvoltage current transformers for the usage in the isolated area of mv switchgear from page 38 0. In the event of an earthfault the sum of the currents is equal to the earthfaul current and a corresponding current flows in the secondary. A power transformer is a static piece of equipment with two or more windings which, by electromagnetic induction, transforms a system of alternating voltage and current into another system of voltage and current usually of different values and at the same frequency for the purpose of transmitting electrical power. Current transformers splitcore, solidcore flexcore. Damping of the ferroresonance in voltage transformers type range tjx. A secondary shortcircuit will cause the unit to overheat and fail in a very short period of time. Design and optimization of medium frequency, medium. Mv indoor current transformer indoor current transformers up to 40. Siemens first began arcfaulttesting its medium voltage drives in 1998. The mfts are very attractive for applications where full. You can also use our live chat tool to speak directly with a. Basic principles the best distribution system is one that will, costeffectively and safely, supply adequate electric service to both present and future probable loadsthis section.
Current and voltage transformer symbols and simplified concepts 5 i 1 i 2 v 1 v 2 symbol of a current transformer symbol of a voltage transformer conceptual picture of a current transformer. Mediumvoltage transformers important requirements for. Medium voltage drives sinamics electric drives simply my. Depending on their particular application, cable current transformers are casted in resin, installed in polycarbonate abs shells or mounted on boards or aluminium tubes.
High resistance grounded neutral high resistance grounding of the neutral limits the ground fault current to a very low level typically under 25 amps. Medium voltage current transformers cable type kola are suitable for the measurement of the sum of threephase currents in a 3phase cable. Mv indoor current transformer documents and downloads. Ansi medium voltage switchgear commonly uses 600volt class window type current transformers in medium voltage circuits. For many years manufacturers have installed 600volt class current transformers in medium voltage switchgear. Instrument transformers are transformers which convert high currents or voltages into measurable and standardized currents or voltages. Medium voltage cables connect the contactor load terminals to the lug landings for the motor load cables. Find your medium voltage transformer easily amongst the 68 products from the leading brands siemens, ge, cg.
By limiting the ground fault current, the fault can be tolerated on the system until. Tg combi 362420 kv combined current and voltage transformer english pdf leaflet emfe english pdf leaflet. Joined merlin gerin in 1981 as consultant and head of the medium voltage export engineering and design department. Medium voltage products current and voltage instrument transformers instruction for installation, use and maintenance. Pfiffner medium voltage ring core current transformers. A set of pullapart terminal blocks connects the contactor.
The direct link into medium voltage secure and simple. Medium voltage products technical guide protection. Indoor supporting current transformer tpu medium voltage indoor current transformers support post type tpu are cast in epoxy resin and are designed for insulation voltages up to 36 kv 40. Polarity and phase relation on ratedvoltage connection. Jfr voltage regulators mediumvoltage outdoor distribution. Current and voltage transformer symbols and simplified concepts 5 i 1 i 2 v 1 v 2 symbol of a current transformer symbol of a voltage transformer. Mediumvoltage current transformers mediumvoltage voltage transformers medium voltage transformers lowvoltage current transformers gmw we make your values visible we provide our customers with our products the entire spectrum to solve everything emas tasks and thus tools for sustainable use of electrical energy.
Our production and test facilities are designed to manufacture and test current transformers also current transformer cascades for a rated current up to 50 ka. Indoor instrument transformers schneider electric belgie. Medium voltage instrument transformers ritz instrument. Ritz instrument transformers medium voltage instrument. Medium voltage drives sinamics electric drives simply. Verify voltage and current rating of circuit breaker are per plans and specifications confirm correct application of manufacturers recommended lubricant. View pdf catalogues and other online documentation. Flexcore maintains a large instock inventory of current transformers, including splitcore, solidcore, low voltage, medium voltage, clampon, and rogowski coils for most common applications. Correct operation of current current, voltage voltage, or current voltage devices usually depends on the relative instantaneous directions. The siemens padmount voltage regulator offers a new dimension to underground system planning and design that preserves an aesthetically pleasing environment. Medium voltage mv indoor current transformer ct cable. In the 1970s, the insulating medium for the higher voltage 534.
Though not yet mandatory, arc resistance requirements are right around the corner. Medium voltage switchgear application guide is based on the analysis of phenomena arising from the behaviour of electrical equipment transformers, motors, etc. Medium voltage products technical guide protection criteria. Generally, the metering its require high accuracy in the range of normal oper ating voltage and current.
We can offer different types of current transformers as. It is used on low voltage systems of 600 volts or less see figure 6. Voltage transformer which is also called as a potential transformer. Silver ribbon element surrounded by silica filler housed in a fiberglass tube and plated endcaps. These are then proportional and inphased to the primary signal. The siemens padmount voltage regulator offers a new dimension to underground system planning and design that preserves an. They are fully insulated from the high operating voltage of the system and are usually bolted to the current carrying device. Excitation current at rated voltage on rated voltage connection. Voltage transformers connected to the mv network primary, they supply the secondary circuit with a reduced voltage value, proportional to the network voltage on which they are installed. Transformer,, abstract medium voltage, medium frequency transformers mfts are much smaller in size and weight compared to conventional low frequency transformers. They may be configured for motor starting, transformer feeders, capacitor feeders, or future sp.
Ratios on ratedvoltage connection and on tap extreme connections. Current transformers reduce high voltage currents to a much lower value and provide a convenient way of safely monitoring the actual electrical current flowing in an ac. The voltage level on the highvoltage side of the transformer must be selec ted according to the gridconnection point. Medium voltage switchgear application guide transformers, motors etc. Design and optimization of medium frequency, medium voltage. Below is a list of all medium voltage current transformers available through flexcore, however, not all models are instock. Ever since, all siemens medium voltage drives have been and continue to be rigorously tested and certified to the most current safety standards, including iec, ul and csa. We offer replacement for siemens transformers, square d transformers, schneider electric dry type transformers, eaton medium voltage transformers, liquid filled medium voltage transformers.
Protection its require linearity in a wide range of voltages. Technical information 4 solutions for power factor correction at medium voltage 20 circutor, s. A 3phase current transformer, 3phase potential transformer and ground fault current transformer are mounted on the contactor when required. Flexcore maintains a large instock inventory of medium voltage current transformers including indoor and outdoor medium voltage current transformers for most common applications below is a list of all medium voltage current transformers available through flexcore, however, not all models are instock. Current transformer for generator designed to work with very high primary currents. Medium voltage technical guide electrical engineering portal. Primary and secondary voltage levels transformers are energized usually from a network which has a defined voltage level that is, the primary feed voltage level. This is an inherent characteristic and cannot be completely eliminated. For pricing and availability of a specific ct model, give us a call at 614 8896152 or use the quote request form. Excitation current at rated voltage on ratedvoltage connection.
Our mediumvoltage instrument transformers are encapsulated under vacuum with epoxy. To check pricing and availability for a specific medium voltage current transformer model, give us a call at 614 8896152 or use our quote request form. Pdf voltage and current balancing in low and medium. When the circuit burden gets too large, the ct secondary voltage becomes distorted.
Medium voltage indoor current transformers are cast in epoxy resin and designed for insulation up to 40,5kv. All medium voltage fuses are limited in their ability to interrupt low value overcurrents, especially those between. Use the links below to browse all transformers from flexcore. Motorpact medium voltage motor controllers general general motorpact medium voltage motor controllers are designed to provide the most efficient means of controlling and protecting a wide range of applications. Solutions for power factor correction at medium voltage. If the transformer noise all alternating current devices that utilize a steel core will emit noise. Noload loss at rated voltage on ratedvoltageconnection. Medium voltage fuses medium voltage fuses mv055 and mv155 specifications description. What is a voltage transformer and a current transformer. Medium voltage distribution catalogue 2012 outdoor.