Scope & facility of Bangla Power in Supply and Service of Electrical Sub-Stations in Bangladesh.

Power Transformer ,Up to 100MVA (132/33 kV)

 

 

Bangla Power takes pride of manufacturing the largest sized power transformers in the South-East Asian region. The best quality transformer comes out from the combined articles of state of the art design feature, cores made of precisely cut sheets, high quality copper winding, clamping structure, voltage adjustment (tappings), well designed tank and conservator, excellent cooling system, and most importantly embedded by protection and control equipment. And of course, stringent tests are carried out to determine conformity to local and international standards. Each production step is operator controlled to ensure the highest quality. Elaborate control procedures and continuous measurements are used to verify the conformance to customer specifications.In order to achieve better reduced losses and low noise levels with smaller core dimensions, core sheets produced with highly developed technologies are used. Generally, the thickness of core laminations is 0.30 or 0.23mm and it is possible or obtain better results with 0.23mm thick laser treated core sheet. CNC machinery is used for lengthwise and broadways cutting to achieve better results with these low loss core sheets.The windings are designed in accordance with the temperature rises, insulation and impulse voltage levels, overload conditions, shortcircuit stresses which are issued in international manufacturing standards. Normally layer winding is used up to 36 kV voltage level and continuous disc winding is used for higher voltage levels. The windings are compressed with pressure segments at the upper and lower yokes in order to encounter the mechanical stresses occurred axially during the short-circuits while the transformer is under service.  Motor drive mechanism is used for the control of on-load tap changer. This control can either be made locally on the transformer or remotely from the control room. The operation of off-load tap changers can either be made on the cover or on the sidewall of the transformer by manual drive mechanism.

On the tanks, there are oil treatment connection valves, oil sampling cocks, lifting lugs, butterfly valves to which radiators are connected and the oil connection valves to other types of coolers in case. All gasket surfaces at the tank are treated with utmost core to prevent unwanted oil leakage. All gasket surfaces are painted with a special point against corrosion. Before painting, outer surfaces of the tanks are sand blasted in accordance with international standards. Conservators are used to compensate the increase of oil volume due to heat. The oil rows from tank to conservator or from conservator to tank through the pipe between cover and conservator depending on expansion and extraction of the oil, air enters or exists the conservator through a dehydrating breather equipped with silica gel particles. To avoid faster aging of the oil, special oil preservation system (Air cell) is used. 

In transformers, the cooling has a special importance to ensure safe operation and to increase the lifetime of the transformer. The heat occurred in the transformers is dissipated at the cooling unit by the help of oil. The simplest and mostly used cooling system is ONAN (Natural Air Cooling with Radiators). ONAF (Radiators Additionally Cooled by Fans) cooling system, in which cooling air is blown to the radiators by fans, is also used.

Transformers are equipped with various protection and control instruments for the operational security. Gases which occur in the transformer for any reason are collected in the Bucholz relay and depending on the volume of gas it gives an alarm or control signal. Pressure relief device replies to the sudden pressure increase that may occur by an arc in the oil of the transformer and gives tripping signal by the contacts on itself. Depending on the oil temperature variations, oil level indicator indicates the oil level in the conservator and gives too low or too high indications by the contacts on itself. Dehydrating breather takes the moisture and dust in the air that enters the conservator and increases service security of the transformer, the amount of silica gel particles in it varies with the amount of the oil in the transformer. Oil thermometer controls the temperature of the oil in the transformer tank and gives alarm and trip signal at the adjusted temperature limit. It gives start and stop signal for the fans used at forced cooling. If remote control is required, PT 100 resistance or 4-20mA output is added to it. Winding thermometer controls the temperature of windings with its monitoring circuit and gives alarm and trip signal at the adjusted temperature limits, like the oil thermometer. Oil flow indicator controls the oil flow at forced oil cooled transformers. It gives alarm signal if oil does not flow for any reason.

Distribution Transformer up to 4.5 MVA (11/0.415 kV):

Bangla Power boasts of modern design and production technique supported by Computer Aided Design and required software. Localand Foreign latest technology and experienced consultants and experts are continuously placing their contributions behind the development of quality production.

Our distribution transformers are ruggedly designed for outdoor and indoor applications. Transformer cores are made of high permeable cold rolled grain oriented (CRGO) electrical steel insulated on both sides mostly imported from Japan, Europe, and USA. Primary consideration is to reduce no load losses, no load current and noise level- high quality core clamping bolts, channels and supports being used.
All of our transformer winding are made of high conductivity electrolytic copper, pin hole free enamels wire. For the HV winding one or more elementary copper strip or super enamel insulated wire are used and for the LV winding one or more copper strip insulated with pure cellulose paper are used.
The tank and cover made of lamination-free, high quality sheet steel, fabricated of a rigid bottom with an oil drainage outlet. After the required components are welded, the first leakage test is performed on the tank.
Bangla Power is probably the only company in private sector has facility for sand blasting to protect the derusting in the high humid country like Bangladesh. An active base coat and two finishing coats are applied in every tank and special tank and paints can be incorporated subject to customer requirement.
Bangla Power uses mostly off load tap changer and on load tap changer as to customer requirement. The tap changers are sourced from the best and proven sources of Europe or best manufacturer. Our tap changers are compact and mounted on the tap of the tank.
Buchholz Relay detects the internal faults and the insulating liquid loss, the alarm contact in the double float design signals oil leakage and/or gases, while a trip contact is activated in the event of severe malfunctions. We provide Buchholz relay as to customer’s requirement.
Thermometer shows the actual oil temperature, alarm and trip signals are provided as protection against over loading and as per requirement of transformer.
After the H. V. and L. V. coils are mounted and centered, the upper yoke is staggered and the core clamping is installed, the cover is also bolted to the upper clamping. The HV winding leads are insulated with paper tube and soldered to the bushing or the tap changer connection. The HV leads are insulated against the upper steel clamping by one press board panel, while another panel fixed the position of the connection wires, the standard wires of the LV bushing are fitted with crimped cable lugs and securely screwed on to the LV winding terminals.
Bangla Power is the only private company probably in Bangladesh using vacuum drying to extract accumulated humidity from the core coil assembly. Immediately after drying, the transformers are tanked and insulating oil are filled with a vacuum oil filtering machine.
Bangla Power ensure quality test facility as to IEC-76, VDE 0537, ANSI C 57.12 and BS 171 and every transformer are dispatched from the factory after being tested properly and passing quality requirements.

Control, Metering, and Relay Panels, Up to 230 kV:

Control, Metering and Relay panels facilitate centralized control of the related controlled equipment in power stations, switching stations and industrial plant. Bangla Power  designs of control, metering & relay panels are based on the concept of unit assembly from standard parts. The panel is built up of separate sheets which consist of front panel, two side panels, door frame, door and roof providing rigidly and strength. The panel has a standard dimension of height: 2350 mm, Width: 400 mm to 900 mm and depth: 500 mm to 1200 mm. Design and manufacture control & relay panel based on Customer’s requirement. The enclosure is constructed by using sheet steel and is equipped with interior lamp, anti-condensation facilities. It is suitable for floor mounting and bottom entry of auxiliary power and multicore cable. Major Compartments/Components of Control Relay Panel: 1. Metering 2. Window alarm fascia 3. Mimic Diagram & control 4. Protection relay Metering Instruments: Ammeter Voltmeter KW Meter/kVar meter Energy meter Frequency meter Power factor meter The panel incorporates control switches and indicator lamps for remote control of controlled equipment. Other Accessories: Healthy trip alarm and test switch Auto/Hand trip counter for circuit breaker All necessary switches, auxiliary relays, interposing transformers, fuses, links, MCB’s test terminal blocks, terminals wiring, lamps and labels etc. The protection relays are equipped for fault protection of system operation. Protection relays are designed and applied to provide maximum discrimination between faulty and healthy circuits. Facilities are provided to give remote signal and audible alarm alerting the control room attendant of the operation of protection devices and mal-operation of power equipment. MIMICS: Strip mimic diagrams incorporating semaphore indication and discrepancy switch. Strip mimic diagrams incorporating semaphore indication and discrepancy switch. Over current and earth fault protection Differential protection REF protection Standby unrestricted earth fault Tripping relay Trip circuit supervision

 

Low Tension (LT) Panel: Bangla Power manufactures low voltage switchgear (hereafter called LT Panel) which is applied for power control and distribution systems of AC 50Hz, rated working voltage up to 440V. It's mainly used in power station, industrial enterprise, Commercial/Residential Buildings for power distribution and can be used to control, protect and inspect the circuit.

The design meets with the standard of IEC439;GB7251. Frame, which consists of zincification steel plate by "C" shaped steel by means of steel rivets and accusing screw. The dimension inside of cabinet and separation cubicles is modular and carried out exchanged of the same unit in specification. Low voltage can endure the discharging; heat and mechanism stress caused by short circuit fault, but also prevent the let and position of press release caused by gas to operator. Switchgear is divided into main busbar compartment, branch busbar compartment, functional units compartment, cable compartment and insulation design of each unit, which can deduct the destroy to lowest degree caused by arc. Frame is without any welding corner, which assured the assemble precision while used of special tools during assembling. Each functional unit is assembled with door (Plate), which are with gemel and lock. The door with facility is not droop caused by weight or size. Each functional compartment is of pressure-releasing avenue. The gas giving out at fault can be released though the avenue. The enclosure can be designed as or "Upper incoming and outgoing"; "upper incoming down outgoing"; "down incoming and outgoing" for the cable or busbar. The dimension of low voltage is: 400mm*1000mm*2200mm (W*H*D) which can be customized at customer’s requirement. The enclosure after processing and mounting is orderliness, propitious and Beauty.

The door, shrouding and frame will be coated with epoxy resin power and not exceed the 50micron prior to acid washing, phosphate, anti-rust paint. After that the enclosure will be of strong anti-corrosive capacity. The color is recommended by us or upon request by customer. The busbar system meets with the requirement of ZBK36001-89, IEC439, IEC694. All the busbar in the cubicle is enclosed in the sub-compartment in the switchgear. The selection of material of busbar is electrolytic copper with high conductance according to the standard of IEC431. The color of phase and order of arrangement are meet with the requirement of IEC439 and GB7251. The fixing bolts of the busbar are of high intensity to make the installation be convenient and flexible and the busbar will be very firm. There are isolated PE earthing system and N neutral conductor which are passing through the device. Section cross of wires: current return circuit=2.5mm2, voltage return circuit=1.5mm2.

PFI (Power Factor Improvement) Plant:
Power Factor of the system is degraded due to inductive load of different industries and big apartments. Bangla Power manufacture PFI (Power Factor Improvement) Plant for improving the degraded Power Factor of the system. We have microprocessor based PFC (Power Factor Correction) relay up to 16 stages. The Capacitors we use are of different ratings (2.5, 5, 10, 20, 25, 50 KVAR…. etc) and corresponding Magnetic Contactor for suitable stepping of the Capacitor bank. Sometimes we also use detuned Reactor with the Capacitors for harmonic filtration of the system. The standard panel size is 600x600x1700 mm (single unit) and the weight is around 200 kg.

Outdoor Off-load Disconnectors:

TYPE OF DESIGNATION: Rated Voltage : 12-245 KV Rated Normal Current: up-to 3150 Amps Versatile design allowing a wide variety of erection arrangements Simple construction Self cleaning contacts Low operating forces required All steel parts hot-dip galvanized. DISCONNECTORS: Bangla Power manufactures outdoor offload disconnectors of the following types : Pantograph – type EPG Centre Break-type ECB Double Break – type EDB The disconnector comprise of the following main assemblies: The main current carrying parts called as the hamper assembly. Support insulators mounted between the current carrying parts and base. The bottom base assembly. The operating mechanism box. Inter-stack, inter phase and down operating pipes. Earthing switch and its operating mechanism box wherever called for. Supporting structure mounted between the base and the ground. Disconnectors can be supplied suitable for horizontal upright mounting on support structure or underhung mounting on substation gantry structure and can be manually operated or motor operated type. PANTOGRAPH TYPE: Rated voltage from 12 kV to 245 kV Rated current upto 3150 Amps Short time current rating upto 50 kA. CENTRE BREAK TYPE: Rated voltage from 12 kV to 245 kV. Rated current upto 3150 Amps Short time current rating upto 50kA. DOUBLE BREAK TYPE: Rated voltage from 12 kV to 245 kV. Rated current upto 3150 Amps Short time current rating upto 50kA. CONTACTS: For pantograph type disconnectors, the current transformer contacts consist of the fixed trapeze type contact mounted directly on the top bus and moving contacts made of copper strips mounted on the pantograph moving blade. PANTOGRAPH DISCONNECTORS: Type: EPG Very low civil engineering profile. Trapeze contact fixing to suit upper bus arrangement. 4 point contact Available for flexible / rigid busbar layouts. Current transformer through multifinger hinge contacts. Individual pole operation. CENTRE BREAK DISCONNECTORS: Type: ECB Very low operating torque Self wiping contacts Simultaneous operation of 3 poles by single operating mechanism up-to 245 kV. Structure to suit requirements. DOUBLE BREAK DISCONNECTORS: Type: EDB Turn and twist contacts Vertical/Horizontal terminal take off Totally enclosed actuator assembly Simultaneous operation of 3 poles by single operating mechanism up-to 245 kV. Structure to suit requirements. DESCRIPTION: The disconnectors consist of separate poles which can be arranged for single pole operation or linked together by operating rods to form 2 or 3 pole units. BASE FRAME: For all sizes up-to 245 KV, the base frame is of welded design and has minimum four fixing holes. EARTHING SWITCHES: Earthing switch can be supplied for mounting as an integral part of the disconnector or for separate mounting as an independent unit operated wither by a manual of motor operating mechanism. OPERATING MECHANISM: Currently the following operating mechanisms are offered: Manually operated mechanism Manually operated geared mechanism Motor operated mechanism. INSULATORS: A wide range of insulators meeting the requirements of IEC-168 of the stack type are available with various cantilever strengths, creepage distances and insulation levels to meet the customer specifications. TERMINAL CONNECTORS: Terminal connectors of rigid or flexible type suitable for horizontal/vertical take offs offered to meet specification. INTERLOCKS: Mechanical constructional interlock is provided between the disconnector and earth switch to ensure that the disconnector cannot be closed when the earth switch is closed and vice versa. INSTALLATION: Disconnectors are delivered in identifiable parts and assemblies. Assembly of Disconnector and commissioning of the same is to be carried out as per the instructions furnished in the erection and commissioning manual supplied along with the equipment. MAINTENANCE: All the bearings provided are sealed for life and need no greasing. All contacts are to be checked and appropriately maintained  and cleaned during annual maintenance. ROUTINE TESTS: 1. RESISTANCE TEST : Operating mechanism Operating universal joints and links Auxiliary contact Inter lock 2. VOLTAGE TEST ON: Auxiliary contact Operating Mechanism  3. FUNCTIONAL TEST ON: Main circuit and attachment Beam and bearing Earthing switch TYPE TESTS: Disconnectors offered have been successfully type tested as per IEC 129 and ANSI 37.30 standards at CPRI, India. STANDARD: The disconnectors are designed to meet the requirement laid down by IEC 129 and ANSI 37.30.   Indoor Type Load Break Switch: This protective equipment is used at 11 kV sub-station. The main Load Break Switch (LBS) mechanism is available for 630A & the over current protection scheme is done through HRC fuse. The panel includes 3 numbers of CT (Current Transformer) & 2/3 numbers of PT (Potential Transformer) for measuring system current & voltage respectively & 3 numbers of HRC Fuses for protection of overload. The scheme is so designed that if fault occurs in any phase it will isolate the whole three phases from the system instantly. The panel also includes 3 numbers of Ampere meters & one number of Voltmeter with selector switch for monitoring system current & voltage. The standard panel size is 900x900x1800 mm & weight is around 450 kg. Spare Parts: Bangla Power Engineering Limited supports customers through the supply of genuine spare parts from the globally reputed and authentic sources. We cater the demand of spare parts through our business network all over Bangladesh as well as in abroad. The storage place at our factory premise is a well managed and controlled temperature and humidity warehouse. Each part is entered, stored, and exited through modern software system. We maintain a huge stock of parts for our own consumption as well as warranty and life time support of the equipments. Protection and Automation: Automation is the use of control systems (such as numerical control, programmable logic control, and other industrial control systems), in concert with other applications of information technology (such as computer-aided technologies [CAD, CAM, CAx]), to control industrial machinery and processes, reducing the need for human intervention. In the scope of industrialization, automation is a step beyond mechanization. Whereas mechanization provided human operators with machinery to assist them with the muscular requirements of work, automation greatly reduces the need for human sensory and mental requirements as well. Processes and systems can also be automated. Bangla Power  provides smart and intelligent solutions for your home, office, and industries. Our Automation and Protection solutions make your power distribution more efficient and reliable. We represent world renowned brands Like ABB, Europe and Mitsubishi, Japan for their protection, and Automation devices to make your facility fully secured and controlled. These products are built to withstand the rigors of the most demanding environments including marine and offshore, industrial facilities such as mines and paper and petrochemical plants, as well as utilities in urban and rural locations. We have the entire range of products to cater your demand suitably. Miniature Circuit Breaker (MCB): Molded Case Circuit Breaker (MCCB): Air Circuit Breaker (ACB): Surge Protective Device (SPD): Magnetic Contactor: Motor Starter: Thermal Overload Relay: Variable Frequency Drive (Inverter): Industrial Voltage Stabilizer: Installation and Commissioning: Bangla Power  is acquainted with the installation and commissioning of thousands of transformers, switchgears, and complete substations in it’s nearly 3 decades long experience. The entire process of installation and commissioning involves the preparation of BOQ, ensuring availability of the right materials at the right quantity at the right time, physical arrangements of transformer, switchgear, ancillary materials, and arrangement of all equipments as per the regulatory authority’s requirement. The ultimate focus on this job is to ensure that safety of the power transmission/distribution equipment, efficient power transmission/distribution, and maximum care for the installation and the environment. The commissioning of the equipments has specific and stringent procedures to avoid premature or wrong operations. It includes the checking of all connections and settings of equipments and ancillaries, load management, test run, and finally supplying power to the grid/loads. Bangla Power has highly expert engineers who are designated only to perform the commissioning jobs. They have received intensive trainings and are of highly experienced to demonstrate perfections in their jobs. Engineering, Procurement, and Construction (EPC): Bangla Power provides complete solution to the customers including engineering, procurement and construction (EPC). We deliver the keys of a commissioned plant to the owner for an agreed amount, just as a builder hands over the keys of a flat to the purchaser. It is also a way that needs the better understanding of customer’s need for perfect execution of a project. An EPC contract is important for several vital reasons. Some are:        The owner puts in minimum efforts for his project and, so, has less stress EPC gives the owner one point contact. It is easy to monitor and coordinate It is easy for the owner to get post-commissioning services EPC way ensures quality and reduces practical issues faced in other ways Owner is not affected by the market rise Investment figure is known at the start of the project Besides the plant sitting, in an EPC contract the owner will define the following: Scope and the specifications of the plant Quality Project duration, and EEL provides total solution to the customers for their power requirement from the project solution activities. Two broad categories of the project solutions are Turnkey, and EPC (Engineering, Procurement, and Construction). It entails project development, BOP development, project engineering, and project management. Our knowledgeable, skilled and experienced engineers are getting involved with the customers through all the stages of project conception, development, implementation, and continuation. It happens from a tiny substation to a large project implementation. Bangla Power has an established department for taking care of the projects. It starts with the concept development, and finishes with the successful implementation of the project. It includes the preparation of project profile, feasibility study, detailed engineering, outsourcing needful, managing resources, and draw fine finishes to the projects. Desirous to be a cutting-edge engineering organization, EEL is relentlessly trying for acquiring excellence in engineering knowledge, preparing BOQ & feasibilities, and practical implementations of the projects. Relevant books are collected and consulted, trainings are received, hands on experience are achieved for establishing proven confidence. Stringent calculations on different engineering aspects of product characteristics, performance analysis, and environmental considerations have been made it possible to reengineer the product, improvement in the quality of installations, and enhancement of performance. Project Management is a function of organizing resources, and timely completion of the project. The project team has to be calculative enough to complete and handover the project within the stipulated time and budget taking in account all the uncertainties, and risks to implement the project at minimum margin of error. Tests: Bangla Power places utmost emphasis on the quality assurance of its products. Rigorous tests are carried out in its manufacturing facility through modern equipments in a controlled environment. We have invested enormously on our testing eWWquipments some of which are: High voltage testing panel Loss measurement panel Insulation testing machine Resistance measuring meter Transformer loss, over voltage, and temperature rise tester Power factor tester Transformer turn ratio tester Inter turn insulation tester Automatic oil tester Lightning tester Routine tests that are usually conducted are: Measurement of voltage ratio and check of vector relationship Measurement of impedance voltage and load loss Measurement of on load loss and current Induced over voltage test Applied voltage test Test on on-load tap changers Type and special tests (The tests that are performed upon request): Temperature rise test Measurement of insulation resistance Measurement of capacity and tangent of insulation loss angle Chopped wave impulse test (1) Measurement of acoustic sound level Measurement of zero sequence impedance Partial discharge measurements (1) Measurement of harmonics of on-load current Measurement of power taken by the fan and oil pump motors Short circuit withstand test. High Voltage Testing Panel Testing Facilities Resistance Measuring Meter Loss Measurement Panel Inter Turn Insulation Tester Transformer Loss, Over Voltage, and Temperature Rise Tester Power Factor Tester Automatic Oil Tester Lightning Tester Insulation Testing Machine Transformer Turn Ration Tester Company Overview: Bangla Power is one of the leading power engineering companies in Bangladesh. Continual research and development, state of the art production facility, quality products, competent services, and countrywide operations have made it warmly acceptable to the customers. Energypac was incorporated in 2004 as a private limited business enterprise. It is powered by 20 skilled manpower of which 05 are graduated engineers. The relentless efforts and dedication of these people are providing continual help to improve technology to innovate and develop new products, just in time delivery, pre and post sales services to maintain a long term business relationship with the customers. To meet countrywide demand of its products and services, Bangla Power has extensive distribution network throughout Bangladesh with full-fledged offices in the major cities like Chittagong, Khulna, Rajshahi, Sylhet, and Bogura. Vision, Mission and Strategy: Vision We will be the most preferred business partner of our customers. Mission We will provide total power solutions to enhance the business of our customers, concurrently creating better technologies that benefit both the customers and the environment. Strategy Our strategic aim is to strengthen the leading position we enjoy in our markets, and to ensure continued growth. We rely on our capability to integrate and deliver solutions from our broad equipment and service portfolio which meet the specific needs of our customer segments globally. Our priority is to offer the best efficiency, reliability and value available. Products & Services: Bangla Power presets a wide range of products and services for its valued customers. Apart from our standard offerings, we provide our clients customized offers suitable to their demands. Our Products: Our illustrative product range includes the manufacturing, marketing and powering with complete solutions or as per customer demand. All of our products are manufactured at controlled environment following international standards like IEC, BS, and ANSI. Our range of products can be broadly categorized as: Transformer Power Transformer Distribution Transformer Instrument Transformer Other Transformers Switchgear Outdoor Vacuum Circuit Breaker Indoor Vacuum Circuit Breaker Control, Metering, and Relay Panels LT and PFI Panels Indoor Type Load Break Switch Disconnecting switch Outdoor Off-load Disconnectors Indoor Type Load Break Switch By-Pass Switches Protection and Automation Spare Parts Our Services: Bangla Power provides comprehensive services to the customers on turnkey basis or as and when required by the customers. Our services are catered but not limited to the followings: Installation and Commissioning Service and Maintenance Engineering, Procurement, and Construction (EPC) Tests: We maintain strict compliance of quality in our entire manufacturing process. Meticulous procedures are followed in every step of the production. To ensure better quality, we use modern testing equipments. Our testing procedure verifies that our design and construction withstands the conditions stipulated by national and international standards. Tests are performed into two main categories: Routine Tests Type and special Tests Marketing Channels and Networks: Bangla Power has an extensive and effective marketing and distribution network across the nation and abroad. Our strong and highly motivated sales and marketing team has undertaken the responsibility to reach our products at all the stores in both the cities and the suburbs. Through the combined effort of our branch offices, and strategic business partners located nation wide and abroad, we ensure proper distribution of our products as per our customer’s need. Contact Us: Contact Us While contacting us, you have several possibilities. Using the links to your right you can find our corporate contact information. Bangla Power Hossain Mollah Electric Market (1st  Floor) 113/3, B.C.C Road, Nawabpur Dhaka-1000, Bangladesh Tel. +880 2 9572251/ 01715-347752 E-mail: biplob_cnyh@yahoo.com Web Site: www.banglapowerbd.com

Indoor Vacuum Circuit Breaker, Up to 33 kV:

Bangla Power is the first and only company in Bangladesh to introduce horizontal isolated, horizontal draw out type vacuum circuit breaker in the country way back in 1998. Large numbers of these circuit breakers are today in operation in Bangladesh and other parts of the world. This specially designed equipment offers following concepts: a) Customer friendly b) High degree of safety c) High operational reliability d) Rugged design e) Simple in construction f) Modular and compact g) Easy maneuverability of truck h) Extensible with high degree of customization The construction is of metal clad type and uses high grade CRCA steel of adequate thickness ensuring safety and security. HHV 12 employs rated vacuum interrupters for arc extinction. The interrupters are procured from most renowned and the best quality manufacturer of the world, CUTLER-HAMMER (EATON), USA. Special characteristics of vacuum interrupters are : a) Very low arcing time b) Quick recovery of dielectric strength c) Small contact gap d) Trouble free service e) Low energy mechanism The mechanism M-37 is of conventional design and is very simple in operation and construction. Mechanism is designed for operation of very short stroke required in vacuum interrupter and is normally charged by motor. When charged, the closing spring is held by a latch which can be released either by manual means or by a solenoid to close the circuit breaker. The energy required for opening is provided by the springs, incorporated in the drive assembly which is compressed during the closing stroke.  The closing mechanism includes the following indications: Breaker on/off Spring charged or discharged The following features are also provided on the switchgear. Operation counter Local on/off switch Local/remote switch All necessary fuses and wiring Cubicle is compartmentalized design in various segregations and bus bars are fully insulated for specified power frequency withstands voltage through use of shrinkable sleeves. Cable chamber is located at the rear of the panel and can accommodate 6 nos. single core 1000 sq. mm. cable or equivalent.  The cable box is designed for cable entry from top or bottom and sufficient head room is provided for cable termination. Relays, indicating instruments and measuring instruments are mounted on a separate chamber. This is a LT chamber and is fully segregated from the other chambers. The relays and meters are mounted on a hinged door and are located at a comfortable height for ease of viewing and maintenance. Where required, earth switches can be provided as an integral part of the equipment. The earth switches are independent in operation to the main closing mechanism, and are interlocked to prevent use when the VCB is connected into its service position. In addition to regular distribution function HHV-12 is ideally suitable for capacitor switching application and auto reclosing duty. HHV-12 is manufactured strictly under technology standards set by the company with the components and subsystems selected through strict quality control procedures as per ISO 9001 certifications guidelines. With its systematically developed technology, the vacuum circuit breaker of type HHV-12 occupies a leading position in networks for electrical power distribution. Applications: Power stations Transformers Chemical industry Steel Industry Automotive industry Airport power supply Cold storage power supply Building power supply Our Circuit breaker is designed for switching: Short circuit current Cables overhead lines under load and no load conditions Ripple control system Capacitor banks Transformers and generators under load and no load conditions Key Features: Long maintenance free operation Fully metal clad design Horizontal isolation Busbar system fully insulated Manual or motor charged main closing mechanism Fully rated with switches Complete set of interlocks and padlocking facilities Isolatable voltage transformer Ample current transformer accommodation Extensive use in tropical environments Safety interlocks TECHNICAL PARTICULARS:  Technical Particulars 11KV 33kV Applicable standard IEC 60056 IEC60056 Type Designation HHV-12 HHV-36 Normal Voltage 11kV 33kV Rated Voltage 12kV 36 KV Frequency 50 Hz 50 Hz Normal rated current 630/1250/1600/2000 Amps 1250/1600/2000 Amps Short circuit breaking capacity 20kA/25kA/31.5kA 25kA Rated 1 Minute Power Frequency Withstand Voltage 28 75 kV Pms Rated impulse withstand voltage 75 170 kV Peak Duty Cycle full breaking capacity Normal 0-3 Min-Co-3 Min-Co 0-3 Min-Co-3 Min-Co Auto reclose 0-0.3 Sec-Co-3 Min-Co 0-0.3 Sec-Co-3 Min-Co