AC Motor Capacitor

I. General
Most of the loads in electric power system are inductive which lead a low power factor. As an enterprise, for the requirement of the electricity, the lower of the power factor, the more capacity of the supply transformer in the condition of the same active power. This will increase the supply investment, and reduce the use factor of the equipments, as well as increase the network circuit lost which impairs the quality of the voltage. Thus, to improve the power factor is an important project for enterprises to save energy and to improve the quality of the electric network. Enterprises shall take some corresponding methods to improve the power factor.
Reactive power compensation is necessary for the improvement of the power factor. The basic principle is to parallel connect the unit of capacitive power load to the inductive power load. While the capacitive load is releasing energy, the inductive load is absorbing it; while the inductive load is releasing energy, the capacitive load is absorbing it. That is, the energy is transformed in between the two loads and thus the reactive power received by the capacitive load is compensated by the reactive power released by the inductive load to reduce the absorption of the reactive power from the electric network.
There are many methods of the reactive power compensation, mainly as follows:
1. To use over-excitation synchronous motor. This method is of complex equipments and high cost, which is only workable when it is large power device drive.
2. To use the phase adjuster as the power supply of the reactive power. This device is of good performance which can improve the stability of the electric power system, but it is of high cost, large investment, high consumption for about 1.8% to 5.5% power consumption per kilovar and complex operation technique.
3. To use static advancer to change the performance of the single motor, to reduce the reactive power and the temperature rise, to increase the output power, to improve the efficiency and to save the energy. But it only applies to wound-rotor motor.
4. To synchronize the asynchronous motor. This method has a certain effect but it is with large self consumption for about 4% to 19% of the reactive power per kilovar, which is generally not adopted.
5. To use the power capacitor for compensating. This method is with convenient installation, short construction period, low cost, easy operation and maintenance and low self consumption for about 0.3% to 0.4% or below of the consumption per kilovar.
There are two methods of the power capacitor as a compensating device:
1. Serial connecting compensation: that is, serially connect the power capacitor to the high voltage electric transmission line to improve the parameter of the electric transmission line, to lower the voltage lost, to increase the output capacity and to reduce the consumption of the circuit. This method is applicable to high voltage remote electric transmission and it is seldom adopted by the electricity enterprises.
2. Parallel connecting compensating: that is, parallel connect the capacitor and the compensating equipments to one circuit to improve the power factor. This compensation method is adopted by all the electricity enterprises.
The main functions of the parallel connecting capacitor compensating the reactive power are:
1. To compensate the reactive power and improve the power factor.
2. To increase the output capacity of the equipment.
3. To lower the energy consumption and the energy lost.
4. To improve the voltage quality.
For improving the electric network quality and other aspects of the enterprise, our company produced WPGJ low voltage reactive power automatic compensating parallel connecting capacitor complete equipment which can improve the power factor of the electric network automatically and increase the voltage quality of the network as well as lower the consumption of the power distribution system and the transformer.

II. Connections with the device


III. Performance characteristic
1. Adopting self-healing capacitor whose performance is far better than oil medium power capacitor. The medium and the poles of the self-healing capacitor have self-healing performance. It is with high density of field, low consumption of the medium, small volume and large capacity.
2. An automatic controller of reactive power compensation has been set which can circulate automatically and switch the capacitor by steps. The switching time interval can be adjusted to keep the reactive power consumption of the electric network at the lowest level, in order to improve the quality of the network voltage efficiently and reduce the consumption of the power distribution system and the transformer.
3. Multiple protections:
1). Single fuse protection
2). Over current protection
3). Over voltage protection
4). Under voltage protection
5). Inrush current and higher harmonic suppression
4. The power factor can be improved to 0.92 or above if the proper capacity is adopted.

VI. Applications
1. The power factor in the enterprise is low and often fined by the supply apartment. The power factor needs to be improved.
2. The voltage of the enterprise substation is low. The voltage of the electric network needs to be increased.
3. The wire lost of the enterprise is too much and it needs to be reduced.
4. Electricity equipments put into use lately.
5. The old capacitors need to be replaced.



                                            
Type specifications of WPGJ1

Type
Single cabinet capacity
Operation steps
Main panel
WPGJ1-1
72
6
WPGJ1-2
96
8
Auxiliary panel
WPGJ1-3
72
6
WPGJ1-4
96
8

Combination modes of WPGJ1

No.
Combination modes
Number of capacitors
Total capacity
Capacity per step
Number of steps
1
WPGJ1-1
6
72
12
6
2
WPGJ1-2
8
96
12
8
3
WPGJ1-1
6
144
24
6
WPGJ1-3
6
4
WPGJ1-2
8
192
24
8
WPGJ1-4
8
5
WPGJ1-1
6
216
36
6
WPGJ1-3
6
WPGJ1-3
6
6
WPGJ1-2
8
288
36
8
WPGJ1-4
8
WPGJ1-4
8
7
WPGJ1-2
8
384
48
8
WPGJ1-4
8
WPGJ1-4
8
WPGJ1-4
8


VI. Use condition
1. Indoor use with good ventilation.
2. Height above sea level shall not exceed 1000m. If exceeds, high-altitude capacitor and other equipments shall be adopted after agreement.
3. Around air temperature is ±40ºC, and the relative humidity is 80%.
4. Installation inclination pitch shall not exceed 5°.
5. No rain on the installation site, any erosive gas or mass dust.
6. No explosion, strong impact or shake.  






VII. Outside view and installation dimensions


VIII. Operation methods
1. Automatic mode: single press function key     to switch the operation mode to manual mode.
2. Manual mode: press up key   to input the capacitor bank gradually. Press down key   to cut off the capacitor bank gradually. Single press function key     to switch the operation mode to automatic mode which press twice (or long press for 3 seconds) to switch to setting mode. Display function code (F-  ).
3. Setting mode: when the function code is displaying, the value of the function code will be changed by pressing up key   or down key   . Single press function key       to switch the operation mode to displaying parameter setting state.
   When the parameter setting is displaying, the setting parameters can be renewed by pressing up key   or down key   . Single press function key     to switch the operation mode to display the next function code (F-  ), while press twice (or long press for 3 seconds) to switch to automatic mode and the cos¢ of the electric network will be displayed at the same time. (Single press means press once within one second and release the key after one second; press twice means release the key after one second and press again at once).
4. The examples of setting
After the controller with powering on displays the cos¢ (or 0.CC) of the electric network, single press the function key    to let the manual light on, and enter the manual state at this time. Press the function key twice (or lasting for 3 seconds) to let the setting light on and enter the setting state at this time. Display the function code (F-  ) and select the setting function code by up and down keys according to the function code table. Single press the function code again also can be done to let the showings in accordance with the setting value. Press the function code key again will display the next function code, in sequence. If set the number of the path, select the function code F-3, and then single press the function key to display the path setting value. Select the setting value by up and down keys. After finish setting, press the function key twice (or lasting for 3 seconds) to return to the automatic state and confirm all the modified setting values now. It will be return to automatic state if there is no key-press within 20 seconds.

IX. Commission
1. Self inspection
The controller displays 000 with powering on and it will display the cos¢ (display 0.CC if there is no current) of the electric network after about 5 seconds and now enter the setting state by the function key to set the self inspection (F-4) to "0". Back to the automatic state and power off the controller after the above was done. Power on again after about 10 seconds and the controller will be in self inspection state and switch off after each switching on. The circulating number is the setting number of the path. The function key can stop inspecting immediately during the inspection process. The controller will automatically cancel the self inspection state after self inspecting and it will not self inspect the next time powering on.
2. Manual test
Press the function key to enter the manual test mode. Press up key to input one capacitor bank and the value of cos¢ at this time will increase or change from lag to lead. Press down key to cut off one capacitor bank and the value of cos¢ at this time will reduce or change from lead to lag.  
3. Automatic test
Positively input the capacitor bank in the manual state to let the cos¢ in lead state and then switch to automatic state. The controller at this time will automatically cut off the capacity bank gradually within the setting time until the cos¢ is displayed between lead 0.99 to the setting value. The normally input capacitor bank can be cut off by force to let the value of cos¢ in low setting value. Then switch to automatic state, and the controller will input the capacitor bank gradually in the setting time until the value of cos¢ is between the setting value and the lag 0.99.

X. Table of function codes

Function code
Name
Setting range
Unit
Min. range
Ex-factory value
F-0
Cos¢
0.90-0.99
0.01
0.98
F-1
Delay
10-99
S
1
30
F-2
Overvoltage
410-470
V
5
430
F-3
Path
1-10(1-7)
1
10(7)
F-4
Self inspection
0.with/1.without
1
F-5
Switching times
Cannot be set
Hundred times
1
0XX

XI. Maintenance and inspection
1. Switch off the isolating switch if any of the followings happens:
a. When the bus bar voltage of the capacitor bank exceeds its rated voltage for 1.1 times or the current going through the capacitor bank exceeds the rated value for 1.3 times.
b. The contact of the capacitor is too hot or burned.
c. There is abnormal noise inside the capacitor or the discharging device.
d. The shell of the capacitor is deformed or expanded obviously.
e. The porcelain bushing of the capacitor discharges seriously with flashing.                                                                                                                                                                                                                                                        
2. When any of the followings happens, do not switch on the isolating switch before the reason has been check out:
a. The isolating switch has to be switched off when the complete unit is without power supply for accident trip.
b. The fuse of the fuse protector is broken.
3. Charging switching on operation is prohibited. The capacitor bank can switch again after finishing discharging for three minutes.
4. The inspection of the operating capacitor bank.
a. When there is a watchman, check per class; when there is no watchman, check at least for one time per week.
b. Mainly check if the capacitor shell is expanded, if there is any oil leak trace, abnormal noise or sparkle, if the fuse is normal and if the discharging indicator light is off.  
c. Record the values of the current meter and the voltage meter. Found out other defaults.
5. Faults handling
a. When the capacitor shell is not leaking heavily, descale it and coat it after welding it with zelco.
b. The capacitor shall be replaced if the shell is expanded.

XII. Quality assurance
The quality assurance of this product shall be handled according to the following rules and regulations:
1.The maintenance period of this product shall be 12 months after purchasing, but should not exceed 15 months after the manufacturing date recorded on the nameplate. However, failures due to the following reasons shall be compensated repairing even in the maintenance period.
Problems due to incorrect operation or impermissible repair and reconstruction of one's own-self.
Problems due to using exceeding the requirements of standard specification.
Damage due to falling or carrying ferociously after purchasing.
Aging or failures of the device resulting from using in the circumstances not conforming to the requirements of this manual.
Failures resulting from earthquake, fire, wind and flood disaster, lightning stroke, abnormal voltage or other natural disasters, or the causes concomitant.
2.You will enjoy the tech support lifetime and paid services whenever and wherever use our product.
The sales, production and agency of this company over the country shall provide after-sale service.
For the products failing to operate, this company has the right to assign other persons to be responsible for maintenance.
3.Matters concerning dissolution of responsibility
This company will not undertake the responsibilities resulting or reducing from using this product departing from the regulations of this manual.
This company will not be responsible for compensating the losses or affected and subsequent damage of your party due to the failure of the product.