Pull Cord Switches

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Pull Cord Switch is a switch that is mounted along a conveyor stringer and is manually actuated by a cord that runs the full length of the conveyor. The cord can then be pulled at any point on the conveyor as an emergency stop.A light switch combined with a light socket is sometimes installed in basement or utility areas of homes. The switch is operated by a pull chain or cord. It is also possible to have the cord-operated switch separate from the light socket, which is particularly common in British bathrooms. Until 2001 it was a requirement of the UK wiring regulations that all bathroom switches were operated by pull cords.

Pull Cord Switches
Pull Cord Switches

Construction

As these Switches are used as safety or emergency switch , it is not operated very frequently therefore construction of these switch is such that it should be operated immediately though it kept idle for long time .Pull cord switch is housed in dust and weatherproof enclosure with IP65 grade of protection. Sturdy and heavy-duty cam-switch with robust contacts is used to give longer service life. Operating handle fitted with spring steel rings at both ends for fixing the rope. The design of the rings gives maximum flexibility in operating condition. Enclosure is epoxy painted to give high corrosion resistance. The switch is designed with manual reset type of mechanism.

Operation

Pull cord switch is mounted on the walkway side of the conveyor belt, preferably at about every 20-25 meters. When the rope is pulled from any side. The switch get operated . Unless and until the handle is reset to normal position manually, the switch remains in operated condition.All the pull cord switches installed along an individual belt are electrically wired in series and connected to the control station by a two core cable. Therefore actuation of any one of these pull cord switches will stop the concerned conveyor until the particular switch is manually reset.