Cantilever Bimetallic Thermal Controls
One advantage of cantilever type controls is that you can customize them to meet the needs of your application. All one has to do, is take advantage of the many different types of bimetals available to easily alter the reactive characteristics. At Portage Electric Products, Inc. (Pepi ®) you are offered a choice of the element used in many of our devices making it easier to meet the specific requirements of your application. Your choice of the bimetal can include choosing a high or low resistance type of element which provides for increased or decreased sensitivity to short circuit conditions in your application. Also, by having a choice as to the type of bimetallic element that best suits the needs of your application, you can tailor the needs of your application which matches the operating specification of the thermal control device. At Pepi ® you have a choice in how it works best for your application.
You also have a choice on the function of the bimetallic element as well. Based on the type of bimetallic element used, you can specify a narrow differential between the opening and closing temperature of the device, a wider differential, or a device that essentially does not reset unless the power source is interrupted, or does not reset at all. Engineers also can choose from many different model variations that are designed in a normally closed configuration where the bimetal element will open the electrical circuit upon increases in temperature or designed in a normally open configuration where the bimetal element will close the electrical circuit upon increases in temperature.
Cantilever type controls which provide for a narrow differential between opening and closing temperatures makes them ideal for temperature control applications where it is necessary to continually make or break the circuit. Cantilever type controls which provide for a wider temperature differential permits lower average operating temperatures in applications where the device is used for over-temperature protection. Variations of these types of controls allow for the device to remain in an open state due to the device having a very low reset temperature that would be much lower than the normal ambient temperatures. This type of device permits for 100 percent testing for function of the device while exhibiting fuse-like operation in the end application. Another variation of this type of control incorporates a heat source either internally or externally to the bimetallic element. This heat source is activated once the bimetallic element opens the circuit current, providing heat to prevent the bimetal from functioning and permitting the device to reclose. The only way the device can be reset, is to disconnect the application from the power source (pull the plug), and the device will reset automatically.