Insulation Boot for Draw-Out Circuit Breaker Contact Arms

About Insulation Boot for Draw-Out Circuit Breaker Contact Arms

On a draw-out medium-voltage circuit breaker, the contact arms that plug into the switchgear are exposed conductors. Contamination, moisture, chemical attack and vermin on or between them are a common cause of flashovers. Gala's insulation boot covers each arm with a close-fitting insulating sleeve.

The boots are moulded from track-resistant cross-linked polyolefin, chosen for electrical insulation and for continuous service at high operating temperature. Each boot slides over a contact arm and is held with fasteners, which are supplied. Because nothing is shrunk or bonded, boots can be removed for maintenance and refitted as often as needed, and a set can be fitted or replaced in a few minutes. The boots protect the arms from corrosion by acids, alkalis and salts, reduce the risk of accidental flashover, and resist UV and ozone, so they suit indoor and outdoor switchgear.

Wall thickness is chosen by system voltage: 1.8 mm minimum for 12 kV, 2.2 mm for 18 kV, 2.8 mm for 24 kV and 3.3 mm for 36 kV class breakers. Boots are made to fit the contact arms of the breaker in question, so send the breaker make and model or an arm drawing with the enquiry. The colour is brick red.

Manufactured by Gala in India. Datasheet and size selection on request.

Specifications

• Brand: Gala
• Product type: Insulating boot for draw-out circuit breaker contact arms, removable and re-usable
• Material: Track-resistant cross-linked polyolefin
• Colour: Brick red
• Voltage rating: Wall thickness chosen by system voltage, 12 kV to 36 kV class (Gala selection chart)
• Operating temperature: -40 deg C to +105 deg C (continuous)
• Size range: Made to the breaker's contact-arm dimensions
• Wall type / thickness: 1.8 mm (12 kV), 2.2 mm (18 kV), 2.8 mm (24 kV), 3.3 mm (36 kV) minimum
• Standards tested to: Test methods quoted on Gala's datasheet - ASTM D638, ASTM D792, ASTM D2240, ASTM D570, ASTM D2671, ESI 09-11, IEC 216, ASTM D2303
• Application: Insulating the contact arms of draw-out MV circuit breakers in power plants and substations
• Installation: Slid over each contact arm and secured with the fasteners supplied; removable
• Country of origin: India

Sizes

• 12 kV | 1.8 mm
• 18 kV | 2.2 mm
• 24 kV | 2.8 mm
• 36 kV | 3.3 mm
• Boot length and bore are made to the breaker's contact arm; supply make and model or a drawing.

Applications: Power plants, transmission and distribution substations, switchgear manufacturers and refurbishers, industrial MV switchboards, switchgear maintenance contractors