AC 3-phase Porcelain Electric Switch for Power System

AC 3-phase Porcelain Electric Switch for Power System

1 The product, suitable for service in a 12kV 50Hz AC 3-phase power system, is a main part of a metal enclosed switchgear. The main contacting knife is used for circuit opening or closing without load, when maintenance of electric equipments during power out, the earthing knife makes a man-made earthing while its closing to guarantee a reliable "ground potential” protection for maintenance personal for safety requirement. It is one of main measures to avoid from electric shock to personal.

2 Features of Main Structure

2.1 On the basis of type GN19 isolating switch, an earthing switch is added to form a new isolating switch GN24-12Q. Every phase conductive part is fixed on a bottom frame by two post insulators. Type GN24-12CQ/630, 1000 or 1250 isolating switch is wall gone-thru type, C means a post insulator is on one side, the other side is a bushing. GN24-12SCQ/630, 1000 or 1250 is double earthing and wall gone-thru type. Three phases of the switch are mounted in parallel. The conductive part per phase consists of a contacting knife, a stationary contact and an earthing knife. There is a pull rod insulator connected at the mid of every contact knife. The pull rod insulator is connected to a main shaft mounted on the bottom frame. Two main shafts for earthing knife and contacting knife are connected respectively by a driven crank arm, and the crank arm is connected to the operating mechanism type CS18-I, CS18-II, CS18-IV or CS18-VI.

2.2 At contacting points for GN24-12CQ/1000(1250) isolating switch (except the bolt fixing contacting of the earthing knife), there is a magnetic locking plate, its role is to strengthen the attract force between two main knives and two earthing knives, enhance the contacting pressure at contacting places, so to heighten the dynamic and thermal stability of the isolating switch while short circuit trouble happens.

2.3 The bottom frame assembly consists of a frame a main shaft and a limit arrester. The limit arrester is used to guarantee the acquirement of the final position needed of main knife and earthing knife while "opening' and "closing".

3 Technical Parameters for GN24-12Q Insolating Switches

Technical Parameters Table

4 Installation and Adjustment

4.1 The isolating switch and operating mechanism can be mounted vertically or declinely in a switchgear.

4.2 Locate the position for a isolating switch according its dimension. Attention has to be paid to the following: while opening and closing of the switch, the insulation distance between the conductive part and earth is not less than 125mm, the distance between the same pole openings of the main knife for combined apparatus is not less than 150 mm, the distance between the same pole openings of the earthing knife of isolating switch is not less than 125 mm.

4.3 An opening signal for main knife of isolating switch has to be given out only after the 75% whole journey for the contacting knife of isolating switch has passed. A signal indicating the isolating switch closing, has to be given out after the reliable contacting between the stationary contact and the isolating switch contacting knife.

4.4 A contacting between the isolating switch main knife, the earthing knife and the stationary contact has to be in good condition. A normal pressure of a spring to the contacting surface should arrive at the value below:

4.5 Earthing of an earthing wire must be good. A resistance for earthing loop never exceed 3Ω.

4.6 A contacting between wiring terminal and busbar connecting should be good, fixed and reliable to avoid a mechanical stress coming from busbar to the isolating switch.

Notes: Detailed technical data and outline drawing shall be provided upon request.

   AC 3-phase Porcelain Electric Switch for Power System

All our goods are packed in wooden cases, with foam inside for protection. And we have a team who is in charge of packing. The team consists of our skilful carpenters and experienced packing designers. These enable our packing reasonable, safe and reliable.

  AC 3-phase Porcelain Electric Switch for Power System

I. Before Sale

a. Contact with clients nearly to know their requirements exactly.

b. Express the requirements from the clients to relevant departments in quickness and exactitude.

II. During Sale

a. Ensure that the products delivered are certified (confirming to the standards of China and IEC).

b. Ensure that marks, handle, package, storage and protection are in accordance with the requirements of ISO 9001/ISO 14001 standards.

c.Transport the products to specified destination as per the contract.

III. After Sale

Our after- sales service is available anytime.

a. Three guarantees will be carried out on the products delivered (18 months quality guarantee). That is refund, replacement and repair.

b. Fittings supply shall be in time.

c. Response for the financial loss brought from the uncertified or services.

d. Product sample is available.

e. Product customization is welcome. We have professional team to meet your requirements.

   AC 3-phase Porcelain Electric Switch for Power System

(GDSH)Guangdong Shui Instrument Transformer Works Co., Ltd. has been in the field of designing and manufacturing power transformers, instrument transformers and related components for more than 24 years. GDSH has two factories based in Sihui City near Guangzhou. Sihu Brand products have the full certificates as below:

·Russia GOST certification;

·China Environmental Symbol Products;

·Guangdong Provincial Energy Saving Symbol Products;

·Excellent conduct enterprise certification with AAAA-level standard; and

·Standardized safety production enterprise with second level

And GDSH pass ISO 9001:2000, ISO 9001/ISO 14001/OHSAS 18001 Quality Environmental and Occupational Health and Safety Management Systems certification.

Our production capability is:

Power transformers 20,000 pieces per year

Voltage transformers 80,000 pieces per year

Current transformers 100,000 pieces per year

Insulating articles 400,000 pieces per year

Quality control

We have more than 50 professional quality inspectors. There are at least 2 quality inspectors distributed at each workshop to make sure every parts of our product are qualified. What’s more, our Test workshop is always capable of stopping non-conforming products to be delivered.

There are 30-45 members in our R&D team

We have a policy of continuous improvement to its product lines.

 And our substantial R & D capabilities are focused on quality and functional enhancements.

Our R&D team provides innovative products to the power grid and other electrical industries.

Our main export market is South Asia, North America, Europe and South America and so on.

   AC 3-phase Porcelain Electric Switch for Power System

Payment terms: 30% deposit in advance and 70% balance paid before delivery or 100% L/C at sight

Minimum order:

For high voltage products and power transformers: 1 piece;

 For medium voltage products: 3 pieces;

For low voltage products and insulating articles: 10 pieces

Delivery time: 5~30 days after receive of order

Quotation Valid Date: 90 days

Transportation methods: By air or by sea, as requested

  AC 3-phase Porcelain Electric Switch for Power System