Thermopile

1. [ THERMOPILE ]
[ Auto Analytical]
Name: - Mohamed Morsy Elsaied

2. 1
[ THERMOPILE ]
- Definition:-
- An electronic device that converts thermal energy into electrical energy.
It is composed of several thermocouples connected usually in series or, less
commonly, in parallel.
Operation: -
- Thermocouples operate by measuring the temperature differential fromtheir
junction point to the point in which the thermocouple output voltage is
measured.
Key Components of Thermopile Detectors
Thermopile detectors consist of an array of thermocouple junctions
linked in series as differential pairs. These differential pairs form the
hot and cold junctions
Circuit of thermocouple :-

3. 2
Differential temperature thermopile(Two Thermocouple):-
- With two sets of thermocouple pairs connected in series. The two top thermocouple
junctions are at temperature T1 while the two bottom thermocouple junctions are at
temperature T2. The output voltage from the thermopile, ΔV, is directly proportional
to the temperature differential, ΔT or T1 - T2, across the thermal resistance layer and
number of thermocouple junction pairs. The thermopile voltage output is also
directly proportional to the heat flux, q", through the thermal resistance layer.
thermopile(Several Thermocouple):-

4. 3
- Thermopiles do not respond to absolute temperature, but generate an output
voltage proportional to a local temperature difference or temperature gradient.
- Thermopiles are used to provide an output in response to temperature as part of a
temperature measuring device, such as the infrared thermometers widely used by
medical professionals to measure body temperature, or in thermal accelerometers to
measure the temperature profile inside the sealed cavity of the sensor
Applications of Thermopile Detectors
 Non-contact temperature measurements in process control and industrial
applications
 Hand-held non-contact temperature measurements
 Thermal line scanners
 Tympanic Thermometers Infrared Radiometry Refrigerant Leak Detection
 Automotive exhaust gas analysis of HC, CO2 and CO
 Commercial building HVAC and lighting control
 Security human presence and detection
 Black ice detection and early warning
 Blood glucose monitoring
 Horizon sensors for satellites, aircraft, and hobbyist applications
 Medical gas analysis such as blood alcohol breathalyzers, incubator CO and
CO2, and anesthetic
 Automotive occupancy sensing
 Automotive HVAC control
 Aircraft flame and fire detection
 Fire detection in transportation tunnels
 Hazard detection including flame and explosion
 Household appliance temperature measurement

5. 4
Application
- Thermopiles are also used to generate
electrical energy from, for instance, heat
from electrical components, solar wind,
radioactive materials, laser radiation or
combustion. The process is also an
example of the Peltier effect (electric
current transferring heat energy) as the
process transfers heat from the hot to
the cold junctions.