Electrothermal Capacitor, Electric Capacitor for Improving Power Factor of Induction Heating

RFM electric capacitor

The operation manual is applicable to the water-cooled electric thermal capacitor with mineral oil impregnated capacitor paper as interelectrode medium for improving power factor of medium frequency electrical system.
RWF type electric thermal capacitor is mainly used in the fixed capacitance part of the circuit, while rwft type electric thermal capacitor is used in the capacitance regulation part of the circuit.
1, Structure
1. The capacitor is composed of the following main parts:
Core: the core is composed of several parallel components. The capacitor element is made of capacitor paper (dielectric) and aluminum conductor (plate). The electrode plates of the elements are protruding out of the medium. One plate is welded with the cooling water pipe and connected with the grounding stud or grounding plate on the cover through the cooling water pipe, which is the total outlet of the plate. The second pole plate is insulated from the shell and connected with the guide rod with a connecting piece, which is led out through the porcelain sleeve on the cover.
Box shell: the case is a rectangle, and there are hanging climbing plates welded on both sides of the box wall for carrying. The cover is equipped with a porcelain sleeve with a number pole and a grounding screw or grounding piece.
2, Technical data
1. The capacitor should be used indoors where the inlet water temperature is not higher than + 30 ºC, and the altitude of the installation site is not more than 1000 meters.
2. The capacitor should work for a long time under the condition of no higher than rated voltage and rated frequency.
3. If the frequency remains at the rated value, the capacitor can operate at 1.1 times the rated voltage for 4 hours in a day and night, but the voltage difference exceeds the rated value in the rest of the time.
4. The capacitance deviation of capacitor shall not exceed ± 20% of the standard value.
The ratio of the maximum capacitance to the minimum capacitance measured between the outlet of RWF type electric thermal capacitor and the outlet of the shell shall not be greater than 1.1
The capacitance deviation measured between the lead-in head and the shell outlet of rwft type electric thermal capacitor for parallel operation shall not exceed ± 20% of the rated value.
5. When the temperature is 25 ± 10 ºC, the tangent value of capacitor loss angle measured under power frequency voltage shall not exceed 0.003
3, Transportation
1. The well packed capacitor can be transported by any uniform speed tool.
2. During transportation, the capacitor should be placed upright with the porcelain sleeve upward.
3. Cap the inlet and outlet of cooling water pipe to avoid blockage.
4, Acceptance
1. When receiving the capacitor, the user should check the correctness of the label and whether there is oil leakage according to the external condition.
2. The withstand voltage test has been done for the capacitor before delivery, so it is not suitable to conduct the withstand voltage test again during acceptance. If necessary, the voltage withstand test can be conducted according to the following test voltage (lasting for 10 seconds).
For unused capacitors: 0.85us.
For used capacitors: 0.75us.
Note: US --- factory test voltage, its value is as follows: DC or AC (power frequency)
For capacitors with frequencies of 1000-4000 Hz, 6ue 3ue
For capacitor 8ue 4ue with frequency 8000 Hz
UE -- rated voltage
Any method to ensure that the relative error of measurement is less than 3% can be used to check the capacitance of capacitor during acceptance.
5, Preservation
The capacitor shall be stored in a room free from rain and snow and without corrosive steam or gas, and the ambient air temperature shall be - 40 to + 40 ºC.
The capacitor must not be placed upside down or stacked.
During storage, there should be no ponding in the cooling water pipe of capacitor, and the inlet and outlet of cooling water pipe should be capped.
6, Use
Vibration is not allowed for capacitor installation. It is allowed to install capacitor close to heater, but non combustible material is used as dense partition wall to enclose capacitor or put capacitor in separate metal cabinet.