Capacitance
split phase compensating thrown-and-cut unit
Product overview£º
IDL-F series Capacitance split phase compensating
thrown-and-cut unit is a kind of relatively advanced
thrown-and-cut unit. Approved by Quality Inspecting
and Testing Center for Reactive Compensation Integrated
Equipment of State Ministry of Power Industry on
Jul.12th, 2003, it is in compliance with the relevant
requirement of Q/32028i\IDCZ02¨C2003 Standard filed
with State Standard Measurement Bureau.
It is usually necessary to carry out power compensation to the circuit due to the inductance components
in the illumination circuit.
In the past, AC contactor was usually used
as switching element. Nevertheless, there will be a heavy
current flowing past the contact of AC contactor at the
moment when the AC contactor is switched in the circuit
just on a voltage peak value because the switching action
occurs so frequently and the voltages at the two ends
of capacitor are unable to change abruptly, so that the
heavy current makes the contact terminals melt, vaporize
and ablate and gradually damages the contacts. In case
that SCR is used alone as switching element, the requirement
for the SCR is relatively high because the illumination
circuit is operating permanently under the conditions
of high voltage and heavy current. Meanwhile, the switching
of SCR will import the crossover distortion from the power
supply to the circuit, which only increases harmonics.
Therefore we now make the cubicle switch integrated the
contact with the SCR component and use it as the switching
element of capacitance compensating controlled circuit,
the thrown-and-cut unit. Thus it will make the capacitance
compensating switching unit more reliable as we bring
the advantages of these two electric components into play
and overcome their disadvantages.
Product model£º
Service condition£º
Diagram of capacitance split
phase compensating thrown-and-cut unit
1¡¢Not exceeding an altitude of 2,500 m
2¡¢Environment temperature: -20¡æ~55¡æ
3¡¢Air humidity: not exceeding 90% at 40¡æ
4¡¢No corrosive gas, electric dust or inflammables and
explosives in the operation environment.
5¡¢Voltage variation range: 160V ¡« 250V
Operation process of capacitance
compensating digital controlled thrown-and-cut unit
1¡¢When the capacitor is switching in:
Receiving the voltage signal outputted by the compensation
controller, the chip-microcomputer begins testing the
operation of the circuit and sends out the turn-on control
signal for SCR. The SCR is turned on when the voltage
is crossing zero and the red indicator (4) turns on. Then
the capacitor switches in and sends out operation signal
for the contactor or relay after a time lag of 0.5-1s;
the contactor or relay operates and green indicator (3)
turns on. The SCR is cut off,the red indicators (4) turns
off and the unit begins its normal operation.
2¡¢When the capacitor is cut off:
Receiving the zero signal outputted by the compensation
controller, the chip-microcomputer detects the blackout
of controlling signal and sends out the turn-on signal
for the SCR. At this point, the voltages at the two ends
of the SCR become zero, then the red indicator (4) turns
on. After a time delay of 0.5-1s, the cut off signal for
the contactor or relay is sent out and the contactor or
relay is cut off. After another time lag of 0.5-1s, the
SCR crosses zero and cuts off, then the capacitor cuts
off and both indicators turns off. The circuit resumes
its initial condition.
The controlling method succeeds in averting the current
surge to the mechanical moving contacts because the SCR
turns on and cuts off and the capacitor switches in and
cuts off all under zero voltage condition, so that the
moving contacts can operate with long lives. Meanwhile,
the SCR only works at the moment when the capacitor throws
and cuts, its operation time being very short. As a matter
of fact, this design brings the advantages of these two
electrical components into full play. ¡¡
The Company adopts the module structure for the inner
cubicle switch of capacitance compensating digital controlled
thrown-and-cut unit, so that the protection properties
of the product are better. In addition, the damage occurred
in the site can be solved simply by replacing the relevant
module, which greatly contributes to easy and fast maintenance.
The capacitance compensating digital controlled thrown-and-cut
unit falls into 2 categories: split compensating unit
and 3-phase compensating unit. As to the 3-phase compensating
unit, only one phase is processed for signal sampling
while 3 phases are processed for compensation and cutting-off
at the same time, which is suitable for the applications
of relatively balanced 3-phase load such as motor and
so on.
As to split phase compensating unit, each phase will be
processed for testing and compensation, so that the circuit
of each phase can acquire the optimum compensation, which
is suitable for street lamp illumination circuit.
The Company attaches great importance to the technology
innovation and dedicates itself to the quality improvement
of its products.
Concerning the key components and heavy duty control elements,
we all adopt imported materials and leave sufficient overmeasure
in the design and selection of materials, so that the
product is ensured to operate effectively for long term.
Diagram for external dimension
and installing size of capacitance compensating digital
controlled thrown-and-cut unit (IDL-F-IV-25A-220V)A£º
Note: (1) Incoming
line of major loop (Power off) (2) Outgoing line of major
loop (load Capacitor) (3) Green indicator (Showing the
thrown-and-cut of compensating capacity) (4) Red indicator
(Showing the thrown-and-cut of SCR) (5) Controlling signal
leg of circuit (6) Controlling signal zero conductor (7)
Mounting hole
Product overview£º
