WSL cage type series-parallel conversion non-excitation tap changer

WSL cage type series-parallel conversion non-excitation tap changer

























WSL cage type series-parallel conversion non-excitation tap changer

Quick Details

Place of Origin: China (Mainland)                           Brand Name: XINCHENG

Usage: Power Transformer or Others                     Model Number: WSL

Max. Current: 2000A                                                Rated voltage: Under 110KV

Application: Voltage regulator                              Type: non-excitation tap changer

Function: Voltage Regulating                               Phase Type: Three

Grade No.: 3 – 10 or others                                     Regulating Position: Central or Others

structures: vertical type                                          Supply Ability: 3500 Set/Sets per Month


WSL cage type series-parallel conversion non-excitation tap changer


WSL cage vision off circuit tap-switch with positive-negative regulating

Functions and Application

Type WSL off-circuit tap changers apply to single pole or three poles oil immersed transformers with the max.

rated through current of 300A,600A,800A,1000A,1200A and highest voltage for equipment of 12 kV, 40.5kV,72.5 kV and 126kV. And the operating position is such: model A is 5 ; mode B is 11. The rated frequency is 50Hz~60Hz.

1 Normal service condition of the tap changer

1.1 The temperature of the transformer oil shall be less than 100, more than -25

1.2 The tap changer shall be kept in the place with ambient temperature from -25~+40, and the relative

humidity shall be less than 85%.

1.3 Vertical inclination of the tap changer should not be over 2% when it is installed on the transformer.

1.4 The tap changer shall be operated in areas without any corrosive or explosive gases.


The specification of the product is rated voltage 110kV(highest voltage for equipment 126kV) and below, rated current 2000A and below with various regulating methods can apply hand-operation and power-driven on the cover or side of the transformer.

WSL Series off-circuit tap changer is used for oil-immersed transformer with on-load tap changer. It is usually of cage type structure. The switch transition type is variable with its inner structure. It has linear regulating , single-bridge stridden over connection, double-bridge stridden over connection, Y-Δ transition, series-parallel connected transition, positive or reverse regulation ate. This tape changer is classified into two type, one called tank head type, the other called bell covered type. The operation method can be classified into two type, one is handled on the tank head or to the grounding, the other is driven with motor, They are used for power transformer, rectification transformer or furnace transformer in following specification range, rated frequency with 50Hz or 60Hz,highest voltage for equipment with 40.5kV,72.5kV and 126kV,rated current with 250A-2000A.This type of tap changer can only be operated in transformer under non-energized condition.

The WSL cage vision off circuit tap-switch with positive-negative regulating is used for oil-immersed off-load voltage-regulating transformer, with vertical and horizontal cage structure. According to different inner structures, the connection mode includes linear regulation, single bridging, twin bridging, Y-△ conversion, serial-parallel conversion, positive-negative regulation. Installation way can be tank-cover-type and bell-type. The tap changer can be widely applicable to power, rectification, furnace and other transformers with rated frequencies of 50Hz and 60Hz, rated voltages of 35kV, 66kV and 110 kV, and rated currents of 125A~2000A. This tap changer must be operated under off-circuit status of transformer

Non-excitation tap switch applies to oil-immersed transformer with 50Hz or 60Hz of rated frequency. In case of no excitation in transformer (i.e. no winding is charged), the switch can be operated manually or electrically to change the tapping position and further to change the transformation ratio, and by this means, secondary voltage can be adjusted or stabilized.

This type of tap changer is comprised by electric, drive me chanism, tap changer body and electric controller with two kinds of specifications standing-type and horizontal-type it is suitable for oil-immersed furnace transformer with rated voltage 40kV and below, rated current 630A and below, they must be working under non-energized condition, it can be operated by electric drive or handle drive.


WSL cage type series-parallel conversion non-excitation tap changer


Product features of round type electrical device:

1)Transformer cover’s round installation opening is smaller and power balance, so its sealing function is better than that of the square’s.

2)Reduce the complex components will make the structure more compact and enable high transmission reliability.

3)The round electric operator operates freely and steadily with high quality of gear shift and small noise.

4)Round series electrical device’s voltage regulating can reach 30 grades and above which leave more space for transformer designing. It’s superior to the others.

5)This patent round electrical switch is in simple structure, advanced function and lower costs. It is economical and safe!

WSL cage type series-parallel conversion non-excitation tap changer


This type off-circuit tap changer consists of gearing mechanism and body, gearing mechanism is on the head of the tap changer, which can be mounted onto top cover of transformer tank; while the body,structured as cage form and without oil compartment, can be mounted into transformer tank.


(1) All gearing components are located inside the compartment above the flange, isolating from

transformer. Gearing components features as compact structure, small size, good appearance and

convenient for maintenance.

Note: The gearing mechanism compartment on the tap changer head should be fully filled with transformer oil before putting into operation.

(2) WSLV and WSLIV series off-circuit tap changer can be affiliated with HMWK-1 controller that can indicate the tap position and operate the tap changer manually by push button at control room.

(3) Clip contact structure, good heat dissipation, reliable contact and strong ability to withstand short-circuit current.

(4) Reliable operation is secured further by electrical and mechanical limit protection.

(5) The control circuit of tap changer controller is interlocked with that of transformer, the power supply of controller is disconnected when transformer is energized, and therefore, ensuring tap changer could not operate in on-load condition.

(6) It is only suitable for standard tank mounting.

WSL cage type series-parallel conversion non-excitation tap changer

1.1 It has independent operating mechanism, which connects with the switch body through operating rod. The operating rod shall be equipped at the time of transformer assembly.

1.2 Contact positioner is installed on the upper wall plate of regular switch body, and it can give you a strong hand feel at the time of tank cover installation and operation so that you can accurately locate the switch contact to the center, therefore, accuracy and reliability of installation and location are improved. Gear indicator is equipped on the positioner, and it indicates 1st gear, 2nd gear, 3rd gear…anticlockwise. There are identification numbers on leading wire, which will provide connivance to you for connecting tapping wire.

1.3 Movable contact is of ring rolling type and strong hand feels for operating, and can be back in place automatically (in case of no undue external resistance). It is generally at the medium gear (at the observation window of the insulating cylinder) when it leaves factory.

1.4 The shaft coupling is with big head (in the direction with high gear number) and small head. The big head and small head shall be respectively inserted into the big head and small head of operating rod notch. Elastic contact device is added on the shaft coupling of switch body, and tightly abuts upon the operating rod. By this means, the generation of floating potential is avoided, and discharge due to operation is eradicated.

1.5 Mechanical retainer is installed on the body positioner or on wall plate. Three-phase switch body is generally equipped with mechanical retainers, while regular 5-gear and 7-gear single-phase switches are not equipped with mechanical retainers so that they can rotate circularly.

1.6   Switch with built-in shielding applies to transformers with high partial discharge requirements and high-voltage transformers, and it can effectively reduce the volume of transformers.


2.1 The contact structure and drum switch are annular pure rolling contact structure, which absorbs the merits of drum switch, such as big working current, automatic arrival in place, small charged body, good stiffness, uniform electric-field distribution and so on. In combination with the structure of wiring terminal of cage switch, this product is developed to replace cage switch and has overcome the demerits of cage switch, such as bad stiffness, big volume, small current-carrying capacity, no operational feel and so on.

2.3 Flat-topped and bell type installation manners are mainly adopted for barrel switch. Switch control mechanism and the body are integral structure without riveting control lever, which makes the installation simpler and more convenient. Floor type installation can also be adopted with control lever for connection and the installation method is the same with drum switch.

3.1 Clip structure shall be adopted for moving contact and is hard to carry big current. Screw drive shall be adopted for the body. The gear shall be switched over after several revolutions (the rev olutions of different types shall be different and the instructions are on the hand grip of control mechanism).

3.2 The installation shall be carried out at Gear 1. The limit (joint end) shall be only set at Gear 1 for the body. Rotate clockwise the joint of switch body to the limit position as Gear 1 and at that time, the moving contact touches the Gear 1 position; remove the protective cover and observe, and when the moving contact stops at the two adjacent fixed contacts

(when leaving the factory, the fixed contacts of switch have been labeled with tapping mark) which are close to the body joint, it is Gear 1.

3.3 Just as drum switch, independent control mechanism is adopted for strip switch. The switch body is connected through control lever which shall be prepared during general assembly of transformer.


4.1   The clip type structure is applicable to the switch with relatively small current. Circumferential rotation of moving contact will realize switchover of gears. In general, switchover of gears will happen after rotation of dozens of degrees.

4.2   Squirrel-cage structure is applicable to the switch with especially big current. The rotation of screw stem will drive moving contact to slide upward and downward axially, so as to realize switchover of gears. Parallel wiring terminal shall be set on fixed contact.

4.3 In general, flat-topped and bell type installation manners shall be adopted without riveting control lever, which makes installation simple and convenient.




1.Open the top cover of tap changer

  1. Drying procedure: under standard atmospheric pressure, heat up the tap changer at a temperature increasing rate of 10C per hour until 110C, and then keep drying with circulating hot air for 24 hours.



WSL Off-Circuit Tap Changers for transformers

Type WSL Off-Circuit Tap Changers are used for adjusting the voltage of oil-immersed transformers. It is designed like a cage without oil compartment and can be vertically installed on the transformer tank cover through top flange directly.

As per different operating modes, there’re three types of tap changer: type motor drive unit tap changer; type ground manual drive tap changer; type hand wheel on the head tap changer. The former can be operated by motor unit while the latter two can be only operated manually.

As per different internal structures,and regulating mode there are six types of tap changer: Type Linear off-circuit tap changer for neutral application; Type Single-bridging off-circuit tap changer; Type Star-delta off-circuit tap changer;

Type Double-bridging off-circuit tap changer; Type Reversing off-circuit tap changer; Type Serial-parallel off-circuit tap changer

As per different sizes, there are two types of tap changer: type A and type B.

There are two type of flange mounting: tank cover type and bell type.

The ground motor drive tap changer is equipped with a motor drive unit. See fig.15 for connection and “CMA9

Motor Drive Unit Instructions” specifies the operating instructions for the motor drive unit.

This instruction contains all the information for installing and operating of the three types off circuit tap changer.











  1. Can you offer test report of the product?
    A: We test every product before packing and delivery. Test report will be provided by requirement.
    Can you offer components of the products?
    A: Yes, we also sell components separately too.
    3. Shall we pay for the sample charges? How to pay and how to deliver us?
    A: For low cost samples, we providing with FOC, customer need to pay for the freight through Western Union etc or providing with freight collection account of courier like DHL, THT, FedEx, the sample will be sent by courier.
    4. Could you manufacture the products according to my drawing or sample?
    A: Yes, ODM is available, we also could manufacture the products according to customer’s drawing or replicate sample.
    5. If new mould is needed, shall we pay for the mould cost? If mould cost will be refunded?
    A: Yes, customer will be asked to pay for the mould cost, this mould cost will be deducted gradually from your orders.
    6. More question
    A:Feel free to contact me, you will get immediately reply


Our main product line:

Tap changer and HV switchgear

Tap changer manufacturing with fullest vertical integration

Tap Changer Products Range On-Load Tap Changer:

Conventional OLTC for transformer with voltage up to 765kV

Vacuum OLTC for oil transformer with voltage up to 765kV

Vacuum OLTC for dry transformer with voltage of 72.5kV

Off-Circuit Tap Changer

Application for the transformer with voltage up to 765kV


WSL cage type series-parallel conversion non-excitation tap changer


The tap changer equipment is shipped as follows:

1 Off circuit tap changer

2 For the tap changer driven by motor drive unit, the tap changer will be delivered with Motor drive Unit type CMA9, middle drive gear box, drive shaft

3 For ground manual drive type off-circuit tap changer, the tap changer will be delivered with hand wheel crank, middle drive gear box and drive shaft.


WSL cage type series-parallel conversion non-excitation tap changer

Packaging & Delivery

Packaging Details

Packaging Details    standard export packing  Carton Box + Wooden Pallet

Delivery Time  2-4 weeks upon deposit

Port: Tianjin, Shanghai, Qingdao

WSL cage type series-parallel conversion non-excitation tap changer

Please Contact Us

 Miss: lydia

Mob: 86-13752439076      Fax: 86-22-60863016

WeChat : 86-13752439076   WhatsApp: 86-13752439076