VM1-T
- VACUUM CIRCUIT BREAKER
4
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2. Structure
2.1 Structure of the operating
mechanism (Figures 9/10 to
9/13 and 9/25)
The operating mechanism is of the magnetic type. It
fundamentally consists of the magnetic actuator 10,
the control module 27 with sensor systems, the
storage capacitors 26 and the linkages which
transmit the force to the breaker poles.
In addition, there are supplementary components
for emergency manual opening and the controls
located on the front of the enclosure.
The actuator 10 acts on the three breaker poles via
lever shaft 18. The storage capacitors 26 provides
the necessary actuating energy on demand.
The mechanical switch positions of the circuit
breaker are detected by two sensors 15 and 16
directly at lever shaft 18.
There are rating plates 7 with the main data of the
switching device on front plate 1.1, and at the left
side in the mechanism enclosure.
The basic version of the magnetic actuator
mechanism is fitted with the following controls and
instruments:
•
ON push-button 3
•
OFF push-button 4
•
Emergency manual OFF 8
•
Mechanical position indicator 6
•
Mechanical operating cycle counter 5
•
Signal lamp for switching readiness 2 (“READY”
lamp).
The following may also be installed:
•
Five-pole auxiliary switches for switch position
signal: -BB1 and -BB3.
2.1.1 Structure of the control module
(Figures 9/13 and 9/15a)
The control module consists of 2 circuit boards:
1. Control board
Control module ED 2.0 produces a voltage of
80 V from any supply voltage within the input
voltage range, with which the storage capacitors
are charged. This is also used to generate a
voltage of 18 V to supply the breaker controller.
2. Power output (upper board)
•
Power electronics for activation of the actuator
coils.
2.1.2 Storage capacitor
(Figures 9/13, 9/15b and 9/25)
The electrical energy for operation of the circuit
breaker is stored in three capacitors. The capacitors
are designed in such a way that the energy for an
OFF-ON-OFF operating cycle is provided without
recharging.
The energy stored in the capacitors is constantly
monitored.
This is accomplished by measuring the capacitor
voltage.
When the supply voltage is applied, the “READY”
lamp indicates the readiness of the circuit breaker
to perform the next switching operation (see
sections 3.1.5 and 6.2).
The energy stored in the capacitors is a criterion for
illumination of the “READY” lamp:
•
Case 1: Breaker in the OFF position.
- The available energy is sufficient for an ON and
OFF operation.
•
Case 2: Breaker in the ON position.
- The available energy is sufficient for an OFF
operation.
- On failure of the supply voltage, the available
energy is sufficient during the initial 180
seconds for an OFF operation (see also section
6.5).
When the energy is not sufficient, a NOT READY
signal indicates that the circuit breaker is not ready
to switch.
2.1.3 Sensor system
(Figures 9/12 and 9/13)
The systematic use of sensors permits control of the
circuitbreaker without auxiliary switches.
Two inductive proximity switches 15 and 16 are used
to detect the mechanical limit positions, which also
provide for self-monitoring of the system.
Summary of Contents for VM1-T
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