Thermo-energy audit
Services for thermo-energy audit
Temperature measurement
Temperature measurement
• Elaboration of a thermo-energy audit or
balance involves analysis of characteristic
data for different energy flows. One of this
characteristic data is thermodynamic
temperature. For measuring
thermodynamic temperature there can be
used different methods and devices that
are presented bellow.
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Temperature measurement
• Obtained data after measurements can be
used for energy efficiency analysis for
different industrial contours. Values of
thermodynamic temperature can also be
used for elaboration of energy balances.
After elaborating thermo-energy audits
and/or balances, using measured data,
there ca be proposed different measures
for increasing energy efficiency.
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Temperature measurement
• Devices that are used for temperature
measurements are characterized by the
precision class. Depending on the
precision class of the device there can be
performed measurements with higher or
lower precision. This fact can influence the
results of a thermo-energy audit or
balance, and finally the energy efficiency.
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Temperature measurement
• It is important to mention that thermodynamic
temperature measurement can be performed
with devices installed permanently on different
technological equipment or with devices that are
only installed for one measurement. Another
important thing is that obtained data can be
stocked, ideally in electronic format, and then
can be used for different analysis for increasing
energy efficiency.
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Temperature measurement
• Glass thermometer with liquid dilatation.
Glass thermometer with liquid dilatation is
based on liquid dilatation (mercury or other
organic liquid) as function of temperature.
• 1 – bulb (sensitivity element)
• 2 – glass capillary tube
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Temperature measurement
• Bimetallic thermometer. Bimetallic
thermometer is based of different dilatation
of two metals that have different dilatation
coefficients, placed together helicoidally.
The free part of the bimetal is connected
to the indicator. Bimetal deformation with
temperature variation leads to moving the
free part and therefore of the indicator.
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Temperature measurement
• Bimetallic thermometer
Calibration bolt
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Temperature measurement
• Bimetallic thermometer
1 – indicator; 2 - bimetal; 3 – fixed connection;
4 – protection; 5 - box
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Temperature measurement
• Gas pressure thermometer. Gas pressure
thermometer is based on pressure change
of a gas within a reservoir with
temperature change (in conformity with
perfect gasses law). The pressure is
measured with manometer and indicated
on the dial.
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Temperature measurement
• Gas pressure thermometer
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Temperature measurement
• Resistance thermometer. Resistance
thermometer is of Pt-100 type. It is based on the
change of resistance of an electric conductor
with temperature.
• Temperature transmitter is set to indicate
temperature for a Pt-100 type sensor. Senzorul
Pt-100 este conectat intr-o configuratie cu trei
fire, pentru a compensa partial erorile de masura
ce apar datorita firelor de legatura lungi.
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Temperature measurement
• Resistance thermometer
• The output data of the transmitter is a
tension, which is sent to a digital display.
The tension is available at two output
jacks, where it can taken by an acquisition
system, and displays it in a field of
0 – 100 ºC, corresponding to inputs of
0 -10 V.
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Temperature measurement
• Resistance thermometer
• Resistance of sensor Pt-100 can be
simulated through connection of display
input to resistances of a measurement
stand:
– 100 Ω corresponding to 0 ºC
– 110 Ω corresponding to 25,7 ºC
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Temperature measurement
• Resistance thermometer
1 – Digital display
2 – Jack Pt100
3 – Jacks for simulation Pt100
4 – Jacks for resistances
(10, 100 and1000 Ω)
5 – Laboratory jacks
(output 0 – 10 V)
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Temperature measurement
• Resistance thermometer
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Temperature measurement
• Thermistor. Thermistor is of NTC type. It is
based on change of resistance of a
semiconductor with temperature: the
resistance of the semiconductor
decreases with temperature increase.
• Thermistor characteristic has a good
linearity only in the field of 20 – 55 ºC,
therefore it can only be used for
measurements in this field of
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temperatures.
Temperature measurement
• Thermistor
• The characteristic is saved in a special
program. The indicated value on the
display is also available as an analog
output signal (0 – 10 V = 0 – 100 ºC), for
the data acquisition system.
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Temperature measurement
• Thermistor
1 – Digital display
2 – Laboratory jacks
(thermistor NTC)
3 – Laboratory jacks
(output 0 – 10 V)
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Temperature measurement
• Thermistor
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Temperature measurement
• Thermocouple. Thermocouple is based on
the Seebeck effect: generation of an
electromotive tension as function of
temperature.
• Thermocouple is of K type. Its
characteristic is memorized in display
program.
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Temperature measurement
• Thermocouple
• The output tension is also available as an
analog signal for the data acquisition
system (0 – 10 V = 0 – 1000 ºC).
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Temperature measurement
• Thermocouple
1 – Digital display
2 – Thermocouple jack
3 – Laboratory jacks
(output 0 – 10 V)
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Temperature measurement
• Thermocouple
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Temperature measurement
• Technical data of thermometers
– Bimetallic thermometer
• Measurement domain: 0 …200 ºC
• Length of the protection device: 160 mm
• Diameter of the protection device: 8 mm
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Temperature measurement
• Technical data of thermometers
– Gas pressure thermometer
•
•
•
•
Measurement domain: 0 …200 ºC
Length of the protection device: 160 mm
Diameter of the protection device: 8 mm
Measurement environment: nitrogen
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Temperature measurement
• Technical data of thermometers
– Resistance thermometer
•
•
•
•
Temperature sensor Pt100
Measurement domain: 0 …200 ºC
Digital display: 0 … 100 ºC
Output signal: 0 … 10 V
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Temperature measurement
• Technical data of thermometers
– Thermistorul
•
•
•
•
•
Temperature sensor: NTC
Measurement domain: 0 … 55 ºC
Resistance: R50 = 359,3 and R25 = 886,2 Ω
Digital display: 0 … 100 ºC
Output signal: 0 … 10 V
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Temperature measurement
• Technical data of thermometers
– Thermocouple
•
•
•
•
Temperature sensor: thermocouple type K
Measurement domain: 0 … 1000 ºC
Digital display: 0 … 1000 ºC
Output signal: 0 … 10 V
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