High Speed DC Circuit Breaker - G E Power Controls

3.2.5 Electro-Dynamic tripping device (code nr: 12)
• ED tripping device requires an external protective relay/system
for monitoring a current increase. This relay/system
belongs to customer’s installation.
• If a fault occurs, an external relay, releases signal into
the capacitors’ control unit (internal NEKO or external),
which discharges abruptly its energy into ED coil [Fig. 8].
The coil trips the breaker’s quick latch and cause opening
within time of less 3ms.
• ED tripping device is offered as an option. Standard set
consist of ED coil and electronic control unit with C-bank
installed in (NEKO). The external release signal shall have
6V to 24V DC, and shall be fed at (-X2 :10 / :11).
• Customer may use it’s own C-bank unit. Rated voltage of
300VDC and capacity of 2000uF is required. In this case
only ED coil will be installed into the breaker.
• Be sure, that voltage level is between 6V…24V and
there are no spikes on signal with duration 3V. In these cases UVR trips the breaker. It is therefore
possible to use this device in combination with the electronic
trip unit for voltage monitoring, i.e. for motor
switches, where an unintended re-start of machines after
a temporary voltage breakdown is to be prevented.
• The UVR is intended for continuous operation. Its rated
power is 40W.
• Due to their operational mode, UVR is self-monitoring
device, i.e. when the breaker is tripped upon a break of
the pilot wire (EMERGENCY-OFF principle).
Fig. 9 Zero voltage release
3.2.7 Forced tripping release (code nr: 13)
Fig. 8 ED tripping coil with seesaw interface
• Optionally, the forced tripping release (FTU) can be installed
in the breaker [Fig. 10a]. This unit is used for mechanical
tripping of the breaker, by means of pressing
the pin at the bottom plate. Force required to trip the
breaker is about 300N (~67,5 lbf).
• The tripping pin position is as on Fig. 10b.
3.2.6 Auxiliary tripping devices (code nr: 11).
• The breaker can be equipped with either a shunt trip (ST)
or a zero voltage release (UVR). It is not possible to have
both devices installed in the same breaker.
• In standard configuration, internal voltage converter
(code nr: 8), supply the devices with 24VDC. This converter
transforms any externally connected voltage, into
internal 24VDC, required by breaker’s controls.
• Optionally, it’s possible to supply both devices with direct
external 24VDC ± 5%. In this case release signal for ST
shall not be longer 100ms.
• Both devices are tripped by potential free contact connected
accordingly.
• Both devices are interchangeable.
• The ST is used for remote actuation. It is designed for
short time operation with maximum duty cycle of 9%.
ST’s supply is connected through the auxiliary contact,
which cut off supply voltage after breaker’s opening.
This protects ST against overheating.
Fig. 10a Forced tripping release
(~0,6 in)
(~0,3 in)
8 Design and specifications are subject to change without notice S47183-e 01/2008