Robertshaw 66004 Series Infinite Switches
Robertshaw® Infinite Switches were designed primarily to help control the temperature of a vessel on a household electric range. They allow an infinite number of heat selections. The infinite is a rotary switch that controls the power dissipated by a heating element. Control is attained by regulating the ratio of time between the opening and closing of the contacts. The cam can provide virtually any infinitely adjustable performance. Housing and cam are molded from general purpose phenolic plastic (heat resistant). The Robertshaw Infinite Switch is a current or series type switch, as opposed to the voltage or parallel type device. This means that its internal bimetal heater assembly is in series with the cycling power contacts, the load, and the applied voltage. These switches normally operate at 240 volts AC, with a current range of 4 to 15 Amps. The advantage of a current switch over a voltage type is the fail safe condition. The bimetal heater is designed to serve as a safety fuse. If the heater opens, no power can be delivered to the load; it safely shuts off power if failure occurs. This prevents a potentially dangerous situation of full on. Robertshaw Infinite Controls deliver superior control at every power setting - low to high. Each unit is ambient temperature compensated for up to 230°F (110°C). All Infinite Switches are UL and CSA listed. Please see the charts on the following pages for shaft lengths and configurations. Mounting can be in any position, including vertical, horizontal or incline. Calibration is not affected by multipoise mounting. Z Type Stem = .188 spring clip. Consider 4590-342 for all 'Z' Type.