Phase Insulated

ATEX certified
Ex e // Ex nA

A well respected, well designed terminal box supplied on multiple GEC manufactured machines as well as those of other OEM manufacture and more commonly known as the BEAMA/CEGB box. Developed in response to industry demands in the early 1960’s and still supplied today, this Phase Insulated box is suitable for Zone 1 and Zone 2 hazardous areas.

Technical Description

The phase insulated terminal box is fabricated from heavy gauge steel plate. Each terminal is protected from adjacent terminals by a steel flash plate, which is integral with the front cover of the box. The terminals are of a stud type, mounted in a glass polyester base, and connected internally to the equipment cables. The intermediate cable lug sockets are securely held by hexagon nuts and locking nuts, and the cable ends shrouded with neoprene caps and seals. The cables pass through a cable spacing block with clamping bolts to the sealing chamber of which two sizes can be fitted.

A deep sealing box is used for supply cables of 185 mm2 and larger. Shallow sealing chambers are used for smaller cable sizes. A pressure relief diaphragm of tinned copper foil is held by a clamping frame in the back of the phase insulated terminal box. In the event of a fault developing between phase and earth, the rapid expansion of gases within the terminal box will fracture the pressure relief diaphragm and direct the path of flame and hot gas outside the equipment carcass from behind the terminal box. Additional ducts and deflector plates can be fitted to direct the flame path in a safe direction, where site conditions make this desirable.

Spares Support

A full range of spares to support this terminal box assembly are available.

Key Contacts


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