GE Industrial Solutions GERAPID 2607, 4207, 6007, 8007 with arc chutes 1X2, 1X4, 2X2, 2X3, 2X4 - Manual (Page 7)

2010-06-07 S47183e rev.03 Design and specifications are subject to change without notice 7
3.2.3 Mechanism
• The Gerapid is equipped with a modular designed
mechanism, which is wear-resistant and nearly
maintenance-free. This mechanism ensures an extended
electrical and mechanical endurance of the breaker as
well as a high level of safety under all operation
conditions.
• Breaker can operate 20 000 cycles when opened by the
shunt trip or zero voltage release, and 1 000 operations
by means of ED impulse coil or OCT releases.
• This mechanism is mechanically latched in the CLOSED
position. The principle of a mechanically latched
mechanism offers a big advantage compared to often
used electro magnet holding system. No auxiliary control
power source is required to keep breaker closed.
• The mechanism is provided with two tripping latches
[Fig. 6]. First latch, called “slow latch”, is used for opening
under normal conditions, like actuation of shunt trip or
zero-voltage release. The second one, “quick latch”, de-
clutches the main contact arm from the mechanism and
opens the contacts with an extremely short delay. This is
used when interrupting short-circuit or overloads. All
safety releases operate onto “quick latch” latch.
• Different main springs are used in mechanisms for
different breaker frames. Therefore mechanisms cannot
be exchange between breakers of different frame.
Fig. 6 Latching and tripping system
3.2.4 Over current release (Code 7)
• The OCT release is a magnet with two magnetic circuits,
optimizing the twin magnetic field principle [Fig. 7]. This
technology ensures equally fast tripping in both current
directions. This system does not require an auxiliary
control voltage to operate. It is a direct acting and
instantaneous tripping device.
• The OCT 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 load
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 load current exceeds the set
static response threshold, the attraction flux (ΦA) [2] takes
over and rapidly pulls down the flexible armature [3].
During this operation, the armature hits 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. The
available ranges are described in the table below. Other
ranges might be possible on request.
• When supplied with the optional transparent side
protection covers (Code 15), a fixed mounted insulated
knob is provided to enable OCT adjustment [Fig. 16].
Fig. 7 OCT device.
Default tripping bands for the OCT release 1) .
No OCT band 2607 4207 6007 8007
1 1,5 kA - 2,5 kA
2 1,5 kA – 3 kA
3 1,5 kA – 4 kA
4 1,5 kA – 5 kA
5 2 kA – 6 kA
6 2 kA – 7 kA
7 2 kA – 8 kA
8 2,5 kA - 5,5 kA
9 3 kA – 7 kA
10 3 kA – 8 kA
11 3 kA – 9 kA
12 3 kA – 12 kA
13 5 kA – 10 kA
14 6 kA – 14 kA
15 7 kA – 15 kA
16 8 kA – 18 kA
17 10 kA – 16 kA
18 12 kA – 24 kA
1) Customer specific bands on request.
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