KSD307-T: Self-hold 1/2” Disc PTC Thermal Cut-out

The KSD307-T series of 1/2” (13mm) self-hold bimetal disc thermostat from Calco Electric Corp offers proven reliability in a wide range of applications. The self-hold construction is integrated with a PTC heater which is electrically located across the contacts. When the contacts are closed, the PTC heater is shunted and therefore not energized. When the contacts are open, the PTC heater is placed in series with the load and is energized to keep the temperature sensitive bimetal in an actuated state. To reset the temperature sensing control, power to the device must be cycled off for sufficient time to allow the assembly to cool to a temperature below the reset point of the bimetal switch. Based on the operational sequence, the KSD307-T is considered having a “manual reset-like” feature although no user actuating mechanism is present.

Features and Benefits

The KSD307-T features include:

• Easy mounting
• Rapid heat transmission
• High durability
• High precision

General Electrical Ratings

The KSD301-M series of controls has been rated by major agencies throughout the world. The agency ratings can be used as a guide when evaluating specific applications. However, the mechanical, electrical, thermal and environmental conditions to which a control may be exposed in an application may differ significantly from agency test conditions. Therefore, the user must not rely solely agency ratings, but must perform adequate testing of the product to confirm that the control selected will operate as intended in the user’s application.

Type and Dimension of Cover

The materials of cover include aluminum and stainless steel. If the thermostat is used to sense the temperature of liquids or steam, the stainless steel unit should be used with this application. See PDF for more details and drawings

KSD307-T: Self-hold 1/2” Disc PTC Thermal Cut-out (PDF Download)