ABB recognised that circuit breakers had reached the point where a major evolutionary step was needed. In particular the market has been calling for greater performance in a more compact design, combined with enhanced control functionality.The company created a new design – the Emax 2. The most obvious difference compared with the previous Emax design is in its size and weight. An Emax2 unit rated for an uninterrupted current of 1250A weighs 32kg, against some 60kg for the equivalent design. It is also the first circuit breaker to offer a large, colour touchscreen display. ControlThe Emax 2 Power Controller function uses a patented algorithm to determine the average power usage over a period of time and then controls a load list to maintain the maximum power usage limit specified by the user. In effect, it will automatically take low priority loads offline as required. The elimination of instantaneous based measurements and ability to synchronise with utility measurement devices creates an efficient environment that saves on electricity bills without the need for additional monitoring systems.The Ekip Link system and Ekip Control Panel enable local monitoring of circuit breakers and switchgear functions in an individual switchboard. They require no programming and are available for even the most basic trip unit, providing an economic way for a small plant to increase its monitoring capabilities or a large plant to simplify local supervision and maintenance.A Network Analyzer feature is available to analyse power quality in real-time, in accordance with EN 50160 and IEC 6100-4 30. As a result, it is possible to identify the causes of increased power outages or a reduction on the service life of cables and capacitors without having to install costly, external instrumentation. The Ekip Synchrocheck module enables the control of the synchronisation condition for placing two lines in parallel before enabling circuit breaker closing. Providing this feature as a module eliminates the need for the purchase and installation of independent monitoring systems.Generator versions of the Ekip Touch and Ekip Hi-touch trip units include all the functions of true generator protection switchgear without the need for external relays or devices, wiring or inspections. The G version offers a safe control solution that is immediately ready for use.ConnectivityEvery Emax 2 can be equipped with multiple cartridge-type communication modules at any time. These allow the circuit breakers to be directly integrated into automation and energy management systems through the seven most popular global protocols; including IEC 61850 for the creation of smart grid networks. All functions can be safely accessed via the Internet, using the Ekip Link switchgear monitoring system.Not only can the rear terminals be field rotated from horizontal to vertical, but they have been specifically designed to fit the most common bus configurations. Each terminal has been created to the standard width of bus bar for that current and is equipped with one, two or three terminal stabs for easy connection of one to four bus runs. The terminal technology provides easy connection and installation with less bus bar stock required.The Supply Module can be connected to any voltage in AC or DC to internally supply auxiliary power for the trip units and terminal box modules consecutively. The need for any external power supply converter elsewhere in the cabinet is eliminated, saving both space and cost.The neutral position can be modified from left to right and the E6.2 model is available with neutral conductor sizes of 50 or 100% to allow for the correct sizing of bus bar and an opportunity to reduce construction costs.PerformanceEmax 2 uses four frame sizes, each only as wide as its current rating requires, so that panel designers can optimize their use of space and material. The breaker design and quality materials allow for a small size while maintaining the high performance required by the most demanding conditions.The Emax 2 family contains: the E1.2, 1600A with a 440V Icu of 66kA and Icw 1s of 50kA in a 210mm width; the E2.2, 2500A with a 440V Icu of 100kA and Icw 1s of 85kA in a 276mm width; the E4.2, 4000A with a 440V Icu of 150kA and Icw 1s of 100kA in a 384mm width and the E6.2, 6300A with a 440V Icu of 200kA and Icw 1s of 120kA in a 762mm width.All models use new generation Rogowski sensors for precise measurements. The tolerance to 1% of the actual value of current, 0.5% of voltage and 2% of power and energy guarantees precision and enables the circuit-breaker to act as a measurement device in switchgear. Measurements can be read directly on the trip unit display so additional devices can be eliminated.The Ekip Fan Module continuously monitors the internal temperature of the fixed switchgear part and activates cooling fans if required. This enables the increased current-carrying capacity.Safety issuesThe touchscreen provides clear, easy navigation for quick access to information and adjustment that is invaluable in the event of a fault or emergency.The trip units can be used in 10 languages, reducing the need for extensive training. In addition, they can be read and used directly, without the need for expensive HMI (human machine interface) units and they can also be programmed and consulted from a tablet, smart phone or PC via the Ekip Connect application.Removal of the main cover allows access to the accessory mounting area only, not the operating mechanism or other components. This protects both maintenance personnel and the breaker itself from unwanted damage. In addition, the key lock accessory is mounted inside the accessory area and allows for the breaker to remain locked, avoiding unwanted operation during maintenance.Dedicated guide rails simplify movement and allow correct, locked and clearly identifiable positioning. The rails extend outside the fixed part so that the mobile part can be easily inserted. In addition, shutters on the fixed part can be locked from the front, without access through the inside of the fixed part. These features allow for easy and safe installation and maintenance.Implementation of breaker settings is simplified with the aid of the company’s DOC software and Ekip Connect interface. Curves and settings can be determined and saved using the software and the program can open and read the file, eliminating the need to retype the settings into the breaker or software program and allowing for easy, error free implementation.The design also contains push-in terminal box technology, making wiring easy and tooling-free. This feature ensures immediate, safe wiring. In addition, terminal boxes and wiring set-ups are common across the line and its trip units are field interchangeable, creating flexibility and the potential for easy, rapid upgrades without the added cost of a service technician.In March 2014, Emax 2 was awarded the Red Dot Product Design Award which has recognised international excellence in product design since 1954. The award recognises its potential to achieve annual worldwide savings equivalent to the consumption of 1.4million EU households per year, or 5.8million MW hours. Case studyOne of the first flagship applications is a diesel-electric ferryboat equipped by Italian electromechanical construction specialist, IMESA. The challenge was to create a switchgear column to feed the vessel’s main distribution system and motors. The column needed to meet four strict criteria set by IMESA’s customer. The first two requirements were for it to be fully selective with downstream circuit-breakers and to offer a short-circuit breaking capacity of 50kA at 600V AC. The second two requirements were for a horizontal bussing distribution system that is compact, to fit within the confines of the vessel’s switch room and to be compatible with withdrawable circuit breakers. The first two challenges call for a category B circuit breaker, while the third and fourth would fit the profile of a moulded-case circuit breaker, which can be mounted in a horizontal position and is compact in size. The Emax E1.2 met all of the requirements. It can be mounted horizontally or vertically, can break up to 66kA at 440V AC or crucially, in the case of IMESA’s installation, 50kA at 690V AC and it is able to withstand 50kA for 1s. The ferryboat installation integrates five units. It also includes the optional add-on module Ekip Measuring, which measures voltage and voltage-related data including power, energy, power factor and frequency. Building on the trip units, each air circuit breaker is also equipped with an Ekip Multimeter, which is a 96mm touchscreen display that displays measurements on a larger screen. Connected to the trip units, the multimeters enable the parameters and protection thresholds to be adjusted onboard. The five units have been installed in a single column which is just 210mm wide, which is 45% smaller than a comparable column of first generation Emax switchgear or of comparable products. The space saved on board the ferry can be put to good use, either in integrating additional electrical distribution equipment or in other operational equipment or in space to accommodate fare-paying passengers. PIC CAPTIONSFigure 1: The Emax 2 power circuit breaker has a touchscreen display.Figure 2: All models use new generation Rogowski sensors for precise measurements.Figure 3: Dedicated guide rails simplify movement and allow correct, locked and clearly identifiable positioning.QUOTE 1The Supply Module can be connected to any voltage in AC or DC to internally supply auxiliary power for the trip units and terminal box modules consecutively. The need for any external power supply converter . . . is eliminated.QUOTE 2All functions can be safely accessed via the Internet, using the Ekip Link switchgear monitoring system.QUOTE 3Implementation of breaker settings is simplified with the aid of the company’s DOC software and Ekip Connect interface.
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