Solid State Devices
Ceramic Type Devices
It is difficult to describe all the variations of ceramic type controls. These controls range from devices which only measure or sense temperature increases or decreases in limited area of an application to that of providing a self limiting heat source.
There are many variations of these temperature measuring devices. These are generally categorized as PTC’s (Positive Temperature Coefficient) or NTC’s (Negative Temperature Coefficient). These are again used for temperature sensing applications and require additional circuitry to actually open and close an electrical circuit. These devices on generally used on low voltage DC circuits and are very accurate in their measurement capabilities.
Although some solid state controls can sense temperature, additional logic is required to do something about it. For example, a solid state device in a laptop computer can sense heat, but needs additional circuitry to tell the cooling fan to do something about it.
Other types of ceramic devices actually are used to provide a heat source for an application as well as provide for a temperature limiting function. Although the first generation of these devices was used for low wattage applications there have been advancements to permit their use on higher wattage applications. These can be used in continuous duty applications and include glue guns, curling irons, and small portable space heaters.