GE Industrial Solutions GERAPID 2607, 4207, 6007, 8007 with arc chutes 1X2, 1X4, 2X2, 2X3, 2X4 - Manual (Page 6)

6 Design and specifications are subject to change without notice S47183e rev.03 2010-06-07
3. Technical information
3.1 Introduction
• Gerapid is a high-speed DC circuit breaker. This is a
single-pole DC breaker, primarily designed for use in
railway power distribution systems with operating
currents up to 8000 A (Code 1) and operating voltages up
to 3600 V (Code 2). Additional applications are special
industrial plants such as electrolysis, mining or steel mills.
• Gerapid breaker 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 enhancement.
• Use the catalogue coding system described in section 7.1
to configure the breaker. Each rating, option or accessory
has own code.
• Closing of the circuit breaker is performed through a high-
power solenoid drive (Code 3).
• During inspections, opening and closing may be carried
out by means of a hand lever (Code 16), which is mounted
onto the armature of the closing drive.
• Overload tripping and release is obtained directly by
means of the OCT release (Code 7), or optionally by ED
impulse release (Code 12). Indirect remote tripping can be
achieved by means of a shunt trip, or optionally by a zero
voltage release (Code 11).
• Gerapid breakers have a compact and enclosed
construction [Fig. 4]. Gerapid is IP 00 protected. All parts
are mounted on thick-walled, non-breakable and
fireproof insulation panels.
Fig. 4 Modular construction overview
3.2 Components and accessories
3.2.1 Contact system
• All Gerapid breakers are equipped with a two-stage
contact system [Fig. 5], consisting of a main contact and
an arcing contact. With this proven design, the main
contact is not subjected to any appreciable wear or tear.
• The main contact is made of a silver composite material.
The arcing contact and link braid are made of copper and
can be easily replaced.
• The flexible bend is linked to the arcing contact by means
of very tight braid.
Fig. 5 Two types of the contact system
3.2.2 Arc chute (Code 2)
•
Compact and modular design of the arc system requires
no additional magnetic support and allows small safety
distances with high breaking capacity.
• Because of the compact dimensions, these breakers can
be installed in extremely small enclosures (from 500 mm;
1.65
ft) and offers a cost-effective solution for
replacements.
• An adaptor [Fig.43] is used to mount the various arc
chutes for different operating voltages on the breakers.
• The arc chutes consist of a highly durable, arc-proof
material, in which 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.