Transformers - Import export

Our mid range frequency converters are delivering up to 250 kW output at frequencies down to 4 kHz. For high frequencies up to 2 MHz we have our high frequency converter series HU.

Twopole and singlepole auxiliary voltage transformers designed to supply control cubicle with low voltage power.

The hermetic Transformer Protection Relay MCHD for hermetically sealed, liquid immersed distribution transformers without gaseous cushion in accordance with EN 50216-3. Each Hermetic-protection relay MCHD is individually tested for tightness and proper functioning.

Pressure relief devices for liquid-immersed transformers open in case of an internal fault and guarantee that the occured overpressure can properly release. Pressure relief devices close with decreasing pressure back to completely closed and leaktight position. Pressure relief devices for transformers can be installed in any position or inclination on the cover or the wall of a transformer. Upon request a transformer can be equipped with several pressure relief valves.

The magnetic oil level indicator 1 225 with vertical float movement is used for hermetically sealed transformers. The float movement is transmitted to the display by means of a magnetic clutch. This ensures that, in case of damage to the dome, no oil leakge of the transformer occures. The body is made of brass. The thread connection of the oil level indicator 1 225 is 1 ½".

The oil drain device Type C2 is used for oil sampling or emptying the transformer tank. The device is welded into the transformer case. The device is designed for use together with connection pipe F DIN 42551 for draining the transformer case for regeneration purpose of the oil. The oil drain device Type C2 is deisgned in accordance with EN 50216-4:2002 type C2.

Dehydrating breathers are being used for liquid immersed transformers in order to protect the insulating liquid and prevent the harmful moisture absorption from ambient air, which occurs when the load on the transformer fluctuates.The dehydrating breather removes practically all moisture from the air that flows through it into the conservator when the transformer is cooling down. This largely prevents any reduction of the dielectric strength and the formation of condensation in the expansion tank. Thus, the dehydrating breathers increases the operational safety of transformers.

The Buchholz Relay MBP in accordance with EN 50216-2 protects liquid immersed transformers and reactors with conservator. It will be mounted in the pipeline between transformer and conservator tank. The Buchholz Relay MBP operates as a protection device that can be provided with either two contacts or four contacts for alarm and tripping. Each Buchholzrelay is individually tested in a test facility for tightness and proper functioning.

These compact half-wave and bridge rectifiers are ideal for installation in space restricted junction boxes of brake motors. They can be delivered with flying leads or terminals for connection. Various accessories are available to meet different installation requirements.

Thanks to extremely compact design the overexcitation rectifier "Slim Collection" can be installed in very restricted space. The module features a central bore for screw fixing inside the terminal box. It can also be installed by using an adhesive pad.

The compact collection is available as bridge, and half-wave rectifiers in two voltage variants. Two different housing variants allow mounting by screwing or snapping in.

The Regular Collection is available as bridge, half-wave, and bridge/half-wave rectifiers. The bridge/half-wave rectifiers reduce the output voltage after the brake is released. Depending on the selected rated coil voltage of the brake, either a faster switching by overexcitation, a reduction of the electrical power while the brake is released or a combination of both is possible.

These half-wave and bridge rectifiers are ideal for installation in the junction boxes of medium-power brake motors, brakes and solenoids. Accessories include flying leads and a range of mounting hardware so that installation on DIN rails is also possible. Encapsulated versions for an extended operating temperature range are available as options. In case of additional DC side fast turn-off, the induction voltage generated by inductive loads is limited within the rectifier.

The rectifier with built-in current sensor for fast turn-off is designed for the operation of electromagnetic devices. It ensures fast turn-on and turn-off. The rectifier with bridge circuit comprises a thyristor and timer. During overexcitation, the rectifier delivers bridge rectified output voltage before changing over to half-wave rectification. On the DC side, the output voltage is enabled by the built-in current sensor which measures the AC current of the connected motor. If the motor is stopped, the rectifier turns off on the DC side as soon as the current falls below the turn-off threshold. The turn-off voltage generated by the inductive load is limited. The rectifier is suitable for connection in parallel with AC motors. The current sensor must be wired into the motor current path in such a way that the current flow created when the motor operates in generator mode will not pass through the sensor. This is crucial to avoid delayed or impaired DC side switching.

These overexcitation rectifiers are designed to increase the attractive force and reduce the attraction time of actuating solenoids, to shorten the coupling and disconnection times of clutches and brakes and to decrease the power consumption of clutches, brakes and actuating solenoids. To increase the attractive force, the solenoid is overexcited during the overexcitation time, applying bridge rectified voltage. Then the rectifier changes over to the selected holding voltage which must not exceed the rated voltage of the solenoid.

ESM for AC-brakes: The module consists of a time-controlled rectifier with integral electronic fast turn-off. During start-up, the ESM delivers bridge-rectified output voltage before changing over to half-wave rectification. The built-in voltage sensor ensures that the DC side output voltage is interrupted electronically when AC input voltage is removed. Thanks to its compact design, the ESM can be installed in very restricted space. ESM for DC-brakes: The module keeps the voltage supplied to the electromagnetic device at a constant level over a wide input voltage and temperature range. Full operating voltage is applied to ensure fast switching when the load is switched on. The module then reduces the power supply to constant holding voltage. A 30% reduction provides power savings of 50%. The ESM is very compact thanks to the use of state-of-the-art microelectronic and power electronic components. Overexcitation time and holding voltage can be factory-programmed to customer demands.

Tavrida Electric's circuit breakers are the perfect match for applications like transformers or generators with a neutral earthing, server rooms and point on wave switching. The circuit breakers weigh less than 14 kg, meaning they can be installed quickly and cost effectively in even the smallest of spaces.

Hotdip galvanized steel mounting kit for Rec15/25 frontal and lateral pole installation. Mounting kit is applicable for all types of wooden, concrete or metal single poles and Hpole structures. Kit could include accessories for control cubicle pole mounting and up to two voltage transformers installation.

Common type wires and terminals to provide a reliable connection between auxiliary voltage transformer and recloser control cubicle.

Custom designed bird guards to provide a protection against wildlife and aggressive environment.

Protection The recloser protects against overcurrent, earth faults, over and undervoltage, over and underfrequency, current and voltage imbalances and many other problems. Measurements The recloser can measure phase, neutral and sequence currents, phasetophase and sequence voltages and threephase active and reactive power and energy. Key measurement data can be logged. Communications The control cubicle has various communication interfaces and can be connected with any third party modem via RS232/RS485 or the Ethernet using various communication protocols, including Modbus, DNP3 and IEC104. Large battery 48hrs operation battery, charged by smart battery charger and maintenance free for up to 10 years. Monitoring Highly comprehensive, remotely accessible separate log files for load and fault profiles, events, malfunctions, lifetime and change messages.

Air insulated switching module incorporates a Tavrida Electric vacuum circuit breaker with a per phase actuator, housed in a corrosion resistant tank. Six main circuit bushings, made from UVstable polymer, are covered with silicone rubber bushing boots. Each bushing has builtin current and voltage sensors for protection, measurement and indication purposes. The outdoor switching module is equipped with six, high voltage bushings with embedded current and voltage sensors. Current sensing is performed by Rogowski coil sensors. Capacitive sensors are used for voltage measurement in all six bushings. Tavrida Electric manufactures small vacuum interrupters with extremely long mechanical and electrical lifespans. A specially designed axial magnetic field distribution provides even current density over the contact surface and significantly improves the vacuum's interrupting performance.

Challenge To execute a pilot project at the Energisa distribution network operator in Brazil within a tight time frame. The customer needed to install 23 kV outdoor circuit breakers with protection at a newly erected substation. Solution Tavrida Electric supplied the Rec25 with substation mounting kit to meet the deadline and satisfy the customer’s requirements in terms of protection. The mounting kit was subjected to comprehensive mechanical tests including overweighting, wind load and seismic impact with successful results.

Tavrida Electric recloser can be used to quickly build costeffective unmanned structure mounted outdoor substation. Provides full protection and automation functionality required at the substation.