G4A01084C Datasheet, PDF (1/22 Pages) List of Unclassifed Manufacturers – MICROTEMP Thermal Cutoffs INTRODUCTION

MICROTEMP^® Thermal Cutoffs:
INTRODUCTION
Upper Limit Temperature Protection
MICROTEMP^® thermal cutoffs from Therm-O-Disc offer an accurate, reliable solution to the need
for upper limit temperature protection. Known as a thermal fuse, thermal link, or TCO, the
MICROTEMP^® thermal cutoff provides protection against overheating by interrupting an electrical
circuit when operating temperatures exceed the rated temperature of the cutoff.
MICROTEMP^® Features:
• One-shot operation cuts off electrical power
• Current interrupt capacity up to 25 amps @ 250VAC
• Low resistance
• Compact size
Operating Principle of the MICROTEMP^® TCO
The active trigger mechanism of the thermal cutoff is an exclusively formulated, electrically
nonconductive pellet. Under normal operating temperatures, the solid pellet holds spring-loaded
contacts closed.
When a predetermined temperature is reached, the pellet melts, allowing the compression spring
to relax. The trip spring then slides the contact away from the lead and the circuit is opened (see
figures 1 and 2).
After a MICROTEMP^® thermal cutoff opens a circuit, the TCO needs to be replaced. This
replacement procedure must include correction of the fault condition before the product is
operated again.
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