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Idiomas disponibles
Idiomas disponibles
Ground Fault (G)
Earth Leakage (G) - Option
I n
t
4
950
(ms)
3
5
800
800
2
10
350
350
230
1
20
230
0.5
30
140
140
Earth Leakage
trip alarm
t
I n
t
I
ZCT or External
CT
Trip Relay Setting
The function for breaking ground fault current above setting value after
time-delay to protect the circuit from ground fault.
1. Standard setting current knob: Ig
- Setting range: (0.2-0.3-0.4-0.5-0.6-0.7-0.8-1.0-Off)×In
2. Time delay setting knob: tg
- Inverse time (I
2
t On): 0.1-0.2-0.3-0.4 sec
- Definite time (I
t Off): 0.05-0.1-0.2-0.3-0.4 sec
2
3. Ground fault current is vector sum of each phase current. Therefore, 3Pole products may operate under its
phase-unbalance including ground fault situations.(R/S/T Phase)
4. When ZSI function was set, the protection operation will take place instantaneously with input absence by
downstream devices. It is advised to disable its ZSI function on the last downstream device.
5. Ground-fault functions are basically provided with products equipped with a trip relay through its internal CT
that is embedded in each phase.(But, it can't be used with earth-leakage protection function at the same time)
The function for breaking earth leakage current above setting value after
time delay to protect the circuit from earth leakage. (A, P, S type)
1. Standard setting current knob: l▵n
- Setting range: 0.5 - 1 - 2 - 3 - 5 - 10 - 20 - 30 - OFF(A)
2. Time delay setting knob: ▵t
- Trip time: 140-230-350-800 ms
- Alarm time: 140-230-350-800-950 ms
3. Settings within its alarm range will prevent its breaker from tripping but activating its alarm.
4. This function is enabled and can be used only with private external CT(secondary output 5A)
selected by customers.
5. When the ZSI function is set, the protection operation will take place instantaneously with
input absence by downstream devices. It is advised to disable the ZSI function on the last
downstream device.
※ USE CAUTIONS WITH EARTH-LEAKAGE CURRENT SETTINGS
- When using other CT selected by customers, the setting range is from 0.5 to 5A based on
its secondary current. (Secondary output rating: 5A)
Hence, under 100:5A CT, if trip relay is set to 0.5A, earth-leakage exceeding 10A will
activate its operation (0.5A x 20=10A)
GUIDELINES FOR USING AN EXTERNAL CT
※
A
- Earth-leakage protection characteristics using the standard CT which is installed inside of
MCCB can protect currents from 20 to 100% range on its rated current.
- As rated currents on MCCB increases, current that is covered by its standard CT increase
as well. This can not protect against small leakage currents.
ex) 400A MCCB Min. Earth-leakage current 400A x 20%=80A
- Therefore, customers are advised to install an external CT in accordance with its rated
currents within its systems. And choose trip relay(E, X type) which is required with CT
usage in order to provide earth-leakage function.
B
- 19 -
GCB800/1200
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