High Speed DC Circuit Breaker - G E Power Controls

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3. Technical informations 3.1 Introduction • Gerapid is a high-speed <strong>DC</strong> circuit breaker. This is a single-pole <strong>DC</strong> breaker, primarily designed for use in railway propulsion-power distribution systems with operating currents up to 8000A (code nr: 1) and operating voltages up to 3600V (code nr: 2). Additional application areas are special industrial plants as electrolysis plants, mines or steel mills. • The breaker type Gerapid has a very high interruption capacity combined with a current limiting characteristic. The arc chute works on the basis of an asbestos-free arc splitting principle. • A wide variety of accessories and spares are available for maintenance, repair, or as a possible extension. The breaker shall be configured by using PST coding system, available at the end of this instruction or as an excel file, free of charge. • Closing of the circuit breaker is performed through a high-power solenoid drive (code nr: 3). • During inspections, opening and closing may be carried out by means of a hand lever (code nr: 16), which is mounted onto the armature of the closing drive. • Overload tripping is obtained directly via OCT device (code nr: 7) or, optionally by electro-dynamic coil (code nr: 12). Indirect remote tripping can be achieved by means of a shunt trip or exclusively, by a zero voltage release (code nr: 11). • Gerapid breakers have a compact and enclosed construction [Fig. 4]. They are IP 00 protected. All parts are mounted on thick-walled, non-breakable and fireproof insulation panels. 3.2 Components and accessories 3.2.1 Contact system • Gerapid breakers are equipped with a two-stage contact system [Fig. 5], consists of a main contact and an arcing contact. With this proven design of the contact system, the main contact is not subjected to any wear or tear. • The main contacts are coated with a silver, composite material. The arcing contact and link braid are made from copper and can be easily replaced. • The flexible bend is linked to the arcing contact by means of very tight braid. Braid Flexible band Arc runner Arcing contact Main contact Fig. 5 Contact system: new (upper) and old (lower) type 3.2.2 Arc chute (code nr: 2) Fig. 4 Modular construction overview • Compact and modular design of the arc system requires no additional magnetic support and allows smaller safety distances with high breaking capacity. • Because of the new compact dimensions these breakers can be installed in extremely small enclosures (from 600mm; 2ft) and offers a cost-effective solution for replacements. • An adaptor is used to mount the various arc chutes for different operating voltages to the breakers. • The arc chutes consist of a highly durable, arc-proof material, wherein the arc plates have been integrated. • The arc plates split the arc into partial arcs and increase the arcing voltage by multiplying the anode and cathode voltage drop. Because of their high heat capacity, the plates and arc chute walls absorb a large amount of the arc’s energy. 6 Design and specifications are subject to change without notice S47183-e 01/2008
3.2.3 Mechanism • The Gerapid is equipped with a modular designed mechanism, wear-resistant and nearly maintenancefree. This mechanism ensures an extended electrical and mechanical endurance of the breaker as well as a high amount of safety for all operation conditions. • This mechanism is mechanically latched in CLOSE position. The principle of a mechanical latch mechanism offers the big advantage, contrary to often used holding magnet system. No auxiliary control power source is required to keep close. • The mechanism is provided with two latches [Fig. 6]. One of the latches, “slow latch”, is used for opening under normal conditions, like actuation of shunt trip or zerovoltage release. The other one, “quick latch”, de-clutches the main contact arm from the mechanism and open contacts with an extremely short delay. This is used in case of short-circuit or overloads. All safety releases operate onto this latch. 3.2.4 Over-Current Tripping device (code nr: 7) • The OCT device is a release magnet with twin magnet circuits, optimizing the twin magnetic field principle [Fig. 7]. This technology ensures an equally fast tripping in both current directions. • The magnetic system does not require an auxiliary control voltage to operate. It uses magnetic energy from the main circuit. • The system consists of the holding circuit [6], the movable armature [3] and the tripping circuit [7]. The holding and the tripping magnetic circuits are both excited by main current [1]. Until the static overload release’s response threshold has been reached, the armature [3] is held in position by the holding flux (ΦH) [2] and the counter spring’s force [4]. Once the main current exceeds the set static response threshold, the attraction flux (ΦA) [2] takes over and pulls rapidly down the flexible armature [3]. During this operation, the armature hit the seesaw, which releases the quick latch in the mechanism. The latch and contacts are opened immediately. • The response threshold can be easily adjusted by turning the adjustment nut with a SW6 hexagon wrench as described in point 2.3.2. • In combination with the transparent side protection covers (code nr: 15), a fixed mounted insulated knob is available to enable OCT adjusting [Fig. 16]. 6 Fig. 6 Latching and tripping system 7 1. Current flow direction. 2. Magnetic core with two fluxes (holding flux ΦH and attracting flux ΦA). 3. Movable anchor. 4. Pressure spring for movable anchor. 5. Short circuit rings. 6. Holding magnetic circuit. 7. Tripping magnetic circuit. Fig. 7 OCT device S47183-e 01/2008 Design and specifications are subject to change without notice 7
Page 1 and 2: GE Consumer & Industrial Power Prot
Page 3 and 4: 1. Warnings and Safety Hints 1.1 Wa
Page 5: 2.2 Installation 2.2.1 Operational
Page 9 and 10: With correctly designed interlock i
Page 11 and 12: • The sensor includes Hall-probes
Page 13 and 14: Control box terminals 1x12-pole AC
Page 15 and 16: 4.2 Terminals wiring system 1 2 3 4
Page 17 and 18: 4.3.2 Voltage converter Voltage con
Page 19 and 20: 4.3.4 NEKO control unit -X16 -X10,
Page 21 and 22: 4.3.6 Shunt trip control unit Emerg
Page 23 and 24: 4.3.8 Indicators -X3 :8 -X3 :12 -X3
Page 25 and 26: 4.3.10 SEL measuring system 1) 2) S
Page 27 and 28: 5.1 Safety distances. Units call in
Page 29 and 30: 5.2.2 Gerapid 2607, 4207, 6007with
Page 31 and 32: 5.2.4 Gerapid 8007 with arc chute 2
Page 33 and 34: 5.2.6 Gerapid 2607, 4207 with V / V
Page 35 and 36: 5.2.8 Gerapid 8007 terminals Gerapi
Page 37 and 38: 6.1.1 General visual inspection •
Page 39 and 40: 6.1.5 Inspection of contacts’ til
Page 41 and 42: D) Install the adapter • [Fig. 48
Page 43 and 44: D) Changing the pre-arcing contact
Page 45 and 46: Fig. 55-4 Unscrew all the plugs fro
Page 47 and 48: 6.3 Spare parts list Component Type
Page 49 and 50: 7.2 Ordering Form. Gerapid with Arc
Page 51 and 52: 7.2.1 Example of order 2. USA custo
Page 53 and 54: 7.4 Troubleshooting. Switching ON i

High Speed DC Circuit Breaker - G E Power Controls

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