Sources of Errors:

There are a number of sources of errors within DTA, and they could lead to inaccuracies in the recorded temperature and weight data. A few errors might be eliminated through placing the thermocouple at proper place and handing it along with the care. For understanding we discuss a few general sources of errors during operation of a DTA.

i)          Buoyance effect: If a thermally inert crucible is heated when empty there is commonly an apparent mass modification as temperature increases. This is because of effect of change within buoyancy of the gas in the sample environment along with the temperature, the rise convection and probable effect of heat from the furnace in the balance itself. Present, in most modern instruments, this effect is negligible. Therefore, if essential, a blank run along with empty crucible can be performed over the suitable temperature range and calibrate the base line by mentioned procedure by individual instruments. The resultant record can be used as a correction curve and results for following experiment performed in the similar condition.

ii)        Condensation on Temperature Sensor: Condensation of the sample will also affect the sensitivity of a thermocouple for temperature measurement. This could be prevented through managing a dynamic atmosphere around the sample within the furnace so in which all the condensable products might be driven through the flowing gases.

iii)       Fluctuation of thermostats.

iv)       Reaction between sample and container

v)         Convection effect from furnace

vi)       Turbulence effect from gas flow

vii)      Induction effect from furnace

It might noted in which errors of type (iii) might be eliminated through properly placing balance within the laboratory and managing constant power supply and error (v) could be prevented through sensible choice of sample container. Last three categories of errors (v-vii) have to be considered within the design of the furnace, the balance and its suspension system. Through preventing excessive heating rate and proper gas flow rate some of above declared errors might be eliminated. To additional minimize errors, DTA equipment should be calibrated both for temperature and peak area determination along with appropriate standards. For temperature substances like KNO₃, In, Sn, SiO₂, BaCO₃, etc. are used depending upon the temperature range used for the experimental condition. For area calibration indium is frequent employed as a standard, but as calibration factor K in case of DTA is temperature dependent, thus, dependium upon the temperature range of the experimental condition other standard are also used.