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6.4 Parameters of the undervoltage release
Rated voltage Ue: AC: 110 V, 230 V, 400 V; DC: 24 V, 48 V, 110 V.
The circuit breaker can interrupt reliably under (35%–70%) Us, and the operating time
is 10 ms–30 ms. When the power supply voltage is less than 35% Ue, the circuit
breaker can be prevented from closing. When the power supply voltage is more than
or equal to 85% Ue, the circuit breaker can be reliably closed.
6.5 See Table 8 for the parameters of the electric operating mechanism.
Table 8 Main technical parameters of the MDX Electric Operating Mechanism
Shell frame level rated current Inm (A)
63
100
250
400
630, 800
Model of electric operating mechanism
MDX0
MDX1
MDX2
MDX3
MDX4
Rated working voltage Ue (V)
AC 110V–230V, 50Hz; DC 110V–220V
Starting current (A)
≤
0.5
≤
2
Operating time (s)
≤0.8
Rated operating frequency (times/h))
180
120
Mechanical life (times)
15,000
9,000
5,000
3,000
The power supply capacity of the electric operating mechanism shall be large enough to ensure that the
voltage applied to the electric operating mechanism under the starting current is not less than 85% Ue.
See Figure 2 for the wiring diagram of the electric operating mechanism.
Figure 2 Wiring diagram of the MDX Electric Operating Mechanism
6.6 Special release with prepaid kilowatt-hour meter
The rated working voltage Ue of the special release with prepaid kilowatt-hour meter
is AC 240 V/50 Hz. It can work normally in the range of (65%–110%) Ue. When the
Ctrl terminal is cut off, the breaker will delay opening by 0.5 s–2 s. See Figure 3 for
the wiring diagram.
6.7 Parameters of the overvoltage release (applicable to 4-pole circuit breaker):
Rated working phase voltage Ue: AC 230 V 50 Hz (or 60 Hz).
Release operation characteristics: When the main circuit phase voltage is (85%–
110%) Ue, the release shall be able to keep the circuit breaker working for a long
time. When the phase voltage of the main circuit rises to 270 (1±5%) V, the release
combined with the circuit breaker shall operate to open the circuit breaker. See Figure
4 for the wiring diagram.
Figure 4 Wiring diagram of the overvoltage release
MDX
type
Closed
Open
R
el
ea
se
Circuit breaker
L1-N
Rated working voltage Ue of
Ctrl-N: AC 240 V/50 Hz
Note: N is connected to
the power neutral wire,
and Ctrl is connected to
the control signal terminal
of the prepaid kilowatt-
hour meter.
R
el
ea
se
P1, P2, UC1 and UC2
on the
release
must correspond to 2, 4, 6
and N on the load side of the access
circuit breaker.
