User Manual

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Thermal Solutions Design Guide | Specifications subject to change
Set point: The temperature at which a controller is set to
control a system. In SmartHeat SLT heaters, the setpoint is
the temperature at which the heater is designed to reach
and maintain.
Shrink band: Pre-stretched strips, that shrink when heat is
applied, for mounting heaters or temperature sensors to
cylinders.
Silicone rubber: A flexible, synthetic elastomer used to
electrically insulate heaters and Thermal-Ribbons™.
SMT (Surface Mount Technology): A printed circuit wiring
method that uses solder pads on the surface of the circuit
to mount components, thereby eliminating through-holes.
Snap action: A switching method, often used in
thermostats, in which a temperature-sensitive bi-
metallic element causes fast make and break of electrical
connections. In contrast to creep action, this method
results in less electrical noise, but requires a significant
differential between temperatures that open and close the
connection, resulting in looser control.
Specific heat: The amount of heat per unit mass required
to raise the temperature of a material 1°C.
SSR (Solid State Relay): A type of relay with no moving
contacts to wear out, offering life many times that of
mechanical relays. Best for time proportioning.
Standard heaters: Predesigned heaters that are made-
to-order. Typical lead time on Minco standard heaters is 3
weeks ARO.
Stretch tape: An elastic, silicone rubber tape for mounting
heaters or temperature sensors to cylinders.
TCR (Temperature Coefficient of Resistance): The average
resistance change per unit resistance between 0°C and
100°C. Sometimes it is simplified to the ratio of resistance
at 100°C to the resistance at 0°C.
Thermal Calc: A Minco web-based program to assist in
calculating heater wattage requirements from known
parameters. Thermal Calc is available at www.minco.com.
Thermal-Clear: A heater made with transparent insulation
and a fine wire element. Thermal-Clear heaters transmit
over 80% of visible light.
Thermal conductivity: A measure of how fast heat travels
through a material. Often referred to as the “k” value.
Thermal-Ribbon sensors: Minco’s family of flexible
temperature sensors, featuring a wide variety of resistance,
TCR, and temperature ranges. Thermal-Ribbon sensors can
be integrated into a heater, or custom designed to virtually
any shape.
Thermistor: A temperature sensor made from
semiconductive material. Thermistors are highly sensitive
(resistance changes dramatically with temperature), but
non-linear and typically not very accurate.
Thermocouple: A temperature sensor made by joining
two dissimilar metals at discrete points called junctions.
Thermocouples produce a small voltage when there is a
difference in temperature between junctions.
Thermofoil: An innovative heating technology from
Minco, which utilizes an etched-foil process to create a flat,
flexible heater for optimum heat transfer. Heaters can be
designed in virtually any shape, and Minco can integrate
temperature sensors, flex circuits, and control electronics.
Thermostat: A temperature-sensitive switch used as an
economical on/off controller, or for overtemperature
protection. See “snap action” and “creep action.”
Thin-film: An electrical component made by depositing
a thin layer of metal on a substrate (usually ceramic).
Thin film techniques can be used to make heaters or
temperature sensors.
Time proportioning: Scaling of output by varying the
ratio of on-time to off-time; i.e. 80% power = 80% full on,
20% off.
TÜV: A testing and certification organization, through
which Minco has ISO 9100 accreditation, and other
approvals.
UL (Underwriters Laboratories): An independent product
safety testing and certification organization, recognized
mostly in the United States and Canada.
ULA: A thermosetting, acrylic adhesive that is UL
recognized.
Vulcanize: A process, using heat and pressure, used to
bond uncured rubber to rubber, metal, ceramic, glass, etc.
WA: A thermosetting acrylic adhesive.
Watt: The heat produced by one ampere of current
through a resistive load of one ohm.
Watt density: The amount of power per unit area, often
expressed as watts per square inch or watts per square
centimeter.