Edison Tank Pump Regulator.
The Edison General Electric Company has just designed and put on the market an automatic switch for use with electrically operated pumps employed in filling water tanks. This is a simple single pole switch with ebonite base, mounted upon an angle piece and operated by a ball float. As the water rises in the tank, the ball float rises with it until it reaches a point where the switch is opened by the operation of aspring. The motor consequently stops and no more water is pumped into the tank. As the water is drawn off, the ball falls with the water level, the switch is closed, the pump starts and continues working until the tank is again filled to the desired point. The ball and all parts coming in contact with the water are insulated from the switch connections and line terminals, so that no part of the circuit can be grounded through the tank. The switch may he screwed to a wall or partition by the side of the tank, or, if convenient, may be placed within and screwed directly to one side of the tank.
The particular switch shown in the illustration is fitted with an arm 7 inches long and a ball 7j£ inches in diameter, and will operate with a variation of 6 inches in the water level. It requires a cubic space of 11^x183^x20 inches, and can be used in any ordinary tank capable of holding more than 30 gallons.
Switches of this type can be used in connection with motors up to two kilowatts capacity, and can be arranged to opperate upon any reasonable change in water level.