Mitsubishi Electric C Series Handling And Maintenance page 47

(b) NF400-CW to NF1600-SEW, NF100-SEP·HEP
A UVT mechanical unit is incorporated in the circuit breaker, and a UVT voltage-control module is
attached outside. Lowered voltage is detected by the UVT voltage-control module, and the UVT
mechanical unit functions to trip. Some are so composed to trip even when the handle of the circuit
breaker is at OFF state but the coil of the UVT mechanical unit isn't energized, while others are
composed for no tripping under this state.
Separate type is the standard for UVT voltage -control module, but a lead wire terminal block can be
attached to the circuit breaker proper.
Circuit
breaker
Connection diagram of UVT voltage module
(Lead wire outgoing)
Connection diagram of UVT
voltage -control module (Lead wire outgoing)
Keep the control voltage within the range of the rated voltage of UVT. Applying higher control circuit
voltage can cause burning of the UVT coil and fire. Applying lower control circuit voltage can result in
malfunction and noise generation in the case of AC.
3 Resettable type and reset prevention type UVT 3 3 3 3
■ Resettable type
The circuit breaker is not made the trip condition even if the UVT coil is not excited when the
circuit breaker handle is set in the OFF or RESET positions. Therefore, when it resets by electric
operation, the UVT coil hold reset status also for no exciting. Moreover, if the breaker is operated
to ON in the state of no exciting the UVT coil, the circuit breaker normally trip. But since the main
contact of the circuit breaker may contact momentarily depending on the breaker model or the
auxiliary switch may change momentarily in with auxiliary switch, please use reset prevention
type for the electrical interlock.
■ Reset prevention type
When the UVT coil is in no excited condition, the circuit breaker can not be operated into OFF
position even if it reset from trip status. If the excitation voltage of the UVT coil returns more than
standard, the circuit breaker can reset in the OFF position.
4 Time delay type UVT 4 4
4 4
(Except for NF2000-S to NF4000-S)
• Operating time of this type has a time lag.
• Operation at instantaneous break down can be avoided.
Type name of UVT module
UVT-MC
U-05S
U-10S
U-05W
U-30W
45
J2
J1
J2
Short circuit protecting
J1
device such as fuse
D2
D1
UVT voltage -control module
CAUTION
Time delay
100ms
(Commonly used for 50/60Hz)
500ms
1s
(Commonly used for 50/60Hz)
0.1·0.3·0.5s
(selectable)
(Commonly used for 50/60Hz)
0.5·1·3s
(selectable)
(Commonly used for 50/60Hz)
Standard
AC100-120
200-240
380-450
DC100-110
AC100-120
200-240
400-450
AC24/48
AC100-120/200-240/380-450
AC200-250/380-450/460-550
DC100-110
AC100-120/200-240/380-450
AC200-250/380-450/460-550
Voltage (V)
Special
AC24
48
440-480
500-550
(Commonly used for 50/60Hz)
DC24
48
AC380-450/460-550/600-690
(Commonly used for 50/60Hz)
DC24/48