Ambient Temperature: The surrounding temperature or environmental temperature.
Trip Temperature: The temperature at which the thermal protector is designed for the contacts to open or close.
Bimetal: Two different metals that bond together to form the disc that actuate the thermostat when reaching a specified temperature.
Close On Rise: Normally open contacts. When the temperature rises to the specified temperature the contacts close.
Contact Resistance: The resistance measured in ohms from across the contacts
Dielectric Strength: The voltage that an insulating material can withstand before breakdown occurs.
Differential: The difference between opening and closing temperatures.
Electrical Contact Rating: The maximum amps and volts that the device has been tested to withstand.
Epoxy Seal: A seal to protect against dust and moisture.
FLA: Full Load Amps, the amount of current on a motor under its normal operation.
LRA: Locked Rotor Amps, the amount of current a motor will pull in a locked condition.
Manual Reset: The thermostat will remain open until reset manually. Also known as a high limit.
Open On Rise: Normally closed contacts. When the temperature rises to the specified temperature the contacts open.
Phenolic: An insulating thermo-set plastic used for the body of specific
Thermostats.
PBT: An insulating thermal resistant plastic used for the shell of
Thermal Protectors. Plastic as it is, PBT is a very good conductor of heat and can resist high temperatures up to 200℃.
Snap Action: Fast sudden change in temperature that will cause the bimetal to snap.
SPST: single pole/single throw. One set of terminals to activate or deactivate a circuit.
Surface Mount: Designed to sense the surface as opposed to the air temperature.
Tolerance: An additional range above or below the nominal set point. The trip temperature and reset temperature of an individual thermal protector are fixed, not sometimes higher and sometimes lower. The tolerance of
Thermal Protectors refers to a batch where the highest and lowest trip temperatures are within the range.
