The ZC series of heat sequencers for the HVAC/R industry are used for staging heaters to prevent circuit overload. Common applications for the sequencers include electric furnaces, baseboard heaters, heat pump blowers, and heating element controls. According to the company, the device uses a positive temperature coefficient (PTC) and bimetal discs to initiate switching action. The PTC is self-current limiting, which is said to ensure stable switching action over a wide range of voltages. Zettler Controls, Inc.
Zettler Controls, Inc.