The Clifton Range - 3 Year Warranty
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High Quality Products at Affordable Prices
EXPLANATION OF TEMPERATURE CONTROL TERMS
Temperature Calibration
Accuracy
We do not provide, claim or assure any form of accuracy. Accuracy is defined as "the ability of a
measurement to match the actual value of the quantity being measured". For accuracy we recom-
mend using a calibrated reference probe at the actual set point temperature and where necessary,
adjust the set point accordingly.
Sensitivity
For an explanation of sensitivity consider a unstirred digital water bath, the PID temperature
control system measures and displays the actual temperature of the water and then compares it
with the ‘set point’ temperature. It automatically calculates and adjusts the required quantity of
heat into the bath to make the measured temperature equal to the set temperature. As with any
process there is a time delay between measuring the temperature and the heat entering the water,
which causes minor fluctuations in the temperature of the bath.
Heat is also distributed in an unstirred bath by convection and conduction and there are heat losses
from the surface of the liquid which can cause temperature losses. These losses and heat distribu-
tion produce small fluctuations in temperature across the water in the bath.
These small temperature fluctuations at any one point are defined as “sensitivity” and vary be-
tween an upper and lower limit, however occasionally a larger variation can be observed. Sensitiv-
ity as stated in DIN 58966 is the temperature difference between the upper and lower temperature
level over 100 cycles after removing the largest 25% of readings.
We determine sensitivity by recording the actual upper and lower temperatures of the bath using
temperature loggers and is stated as plus or minus one half of the measured value.
Uniformity
Uniformity is calculated by measuring the temperature in opposing ends of the water bath and is
the difference between the mean temperatures at these two points and stated as plus or minus
half this value.
POWER INTERRUPT DURING TIMER MODE
If power is interrupted during timer mode, the display shows P.OFF when resumed.
To clear, press and hold the RUN button until display reverts to actual temperature.
Timer mode will then continue. To deactivate timer, press and hold RUN button.
