43
42
Temperature: -25°C~+70°C (average temperature up to +35°C within 24h)
Altitude: up to 2000m
Press test
button once a month, to ensure the long-term stable operation.
Operating environment
Maintenance requirements
Alarm
contact (AL)
Accessories
Ex9ML can be installed with alarm contact for extra functions including “Alarm but no release” or “Alarm
and release”.
Note: The above functions are available upon request, however the accessories must be installed by
Noark.
Residual current protection
Ex9ML series residual current protection circuit breaker consists an Ex9M circuit breaker and a residual
current protection model (can be provided separately, please contact Noark for details). The circuit
breaker does not need any external power supply and should be directly installed under the 3-pole or 4-pole
circuit breaker. With adjustable rated residual current operating current and residual current release time,
the circuit breaker provides backup protection for direct contact and protection for indirect contact.
The residual current release complies with the following standards:
IEC 60947-2; GB/T 14048.2 Appendix B
IEC 60255-3 and IEC 61000: Preventing unnecessary release
IEC 60255-4 and IEC 1-2~5: With resistance to instantaneous overvoltage, lightening, static
discharge and radio-frequency interference.
Function
Provide indirect contact protection for human body, the exposed conductive parts of the
equipment should be connected to the grounding pole
Provide residual current protection for building power distribution system and similar equipment
Provide detection and protection of long-existing grounding fault due to non-operation of
overcurrent protection device
Key parameters
Operation interface
1. Power indicator
2. Residual current operating setting
3. Limit non-actuating time setting
4. Reset button
5. (Residual current) test button
Model
Rated residual current
operating setting
Residual
current
type
Limit non-actuating time setting
Ex9ML1
0.03-0.1-0.3-1(A)
0.05-0.2-0.5-2(A)
A/AC
∆
t(ms): 0
- 60 -
200
-
500
Maximum breaking
time t (ms):
100 -
300
- 500 - 1000
Ex9ML2
0.03-0.1-0.3-1(A)
0.05-0.2-0.5-2(A)
Note: the set time is correspond to the breaking time
below; when the residual current is set to 0.03A, the
limit non-actuating time must be set to 0.
Ex9ML3
0.03-0.1-0.3-1(A)
0.05-0.2-0.5-1(A)
0.1-0.3-1-2(A)
Residual current protection circuit breaker with high sensitivity
Selective protection
Selective protection means when there is a fault occurred at any point in the grid, only the
upstream circuit breaker will disconnect the fault circuit. The Ex9M series circuit breakers provide
selective protection function. When fault happens, override tripping or multistage tripping can
occur in power grid without selective protection, which can cause widespread blackout, economic
loss, equipment damage and personal injury.
Three types of selective protection:
Complete selectivity: Provides selective protection to all overload and short circuit currents.
Local selectivity: Provides selective protection to fault currents smaller than a certain level.
No selectivity: The upstream and downstream circuit breakers operates at the same time when
a fault occurs, which means there is no selective protection.
See “Curves and Parameters” for the detailed parameter table of the selective protection of
Ex9M series circuit breakers.
Notes for using cascade protection
●
The upstream circuit breaker must have current limiting capability.
●
The maximum breaking capacity of the upstream circuit breaker must be bigger than the
expected short circuit current value of its installation point.
●
The energy goes through the upstream circuit breaker must be within the allowable range of
the protected line.
●
The protection can include more than two levels instead of just upstream and downstream
circuit breakers.
●
The “enhanced” breaking capacity of the downstream circuit breaker is determined by
upstream circuit breaker.
●
The cascade protection table of Ex9M is provided by Noark.
Please refer to different cascade table for different system voltage
●
If the upstream circuit breaker is located between the phase line and the neutral line of 3-phase
4-line grid, with rated voltage of 220/240V, and the rated voltage of downstream circuit breaker
is also 220V, please refer to the 220/240V cascade table.
●
If the operating voltage of the upstream circuit breaker is 380V, the downstream circuit breaker
is also 380V or is 220V but located between the phase line and the neutral line, please refer to
308V cascade table.
●
Please refer to “Curves and Parameters” for the detailed parameter table of the cascade
protection function of Ex9M.
Cascade protection
Cascade protection uses the current limiting capability of upstream circuit breaker (Ex9M) to
shield the short circuit current so that the short circuit current pass through the downstream
circuit breaker will be much smaller than expected. User can choose a circuit breaker with
breaking capacity smaller than the expected short circuit current at installation point to reduce
the cost of the entire electrical system.
For example: As shown in the right figure, when there is short circuit current at D2, the upstream
circuit breaker D1 will detect the current, and if D1 has current limiting capability, it can reduce
the short circuit current in the entire circuit. In this case, it’s like D1 has undertaken a part of the
short circuit current for D2 which enhanced the breaking capacity of D2 so D2 can cut off a short
circuit current that is bigger than its maximum breaking capacity.
D
1
D
2
Ｎ
Ａ
Ｎ
Ａ
Ｂ
Ｃ
Ｎ
Ａ
Ｂ
Ｃ
Functions
Functions
Ue AC380/400/415/440V
f 50/60Hz In≤160A
GB/T 14048.2
IEC/EN 60947-2
Ex9ML1
2
1
4
3
6
5
N
N
T
1
4
5
2
3
