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Hikvision DS-2TP31 series Thermal Camera Teardown

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Hikvision cleverly incorporated a very accurate FFC shutter design that is used as a calibration reference for the microbolometer measurement process. The standard DS-2TP31 camera uses a conventional “free air” open FFC flag that is vulnerable to temperature errors at the point of flag temperature measurement. Image stacking also appears to have been employed but I do not know the exact purpose of this except to create an average sample for measurement.

I totally agree that the use of thermal imaging cameras was a mixture of science and ‘wishful thinking’ It is very difficult to accurately measure a human's core temperature at a distance, using a thermal camera.That is a topic that has been covered before on this forum though. What impressed me with ten DC-2TP31B  was that the design had been enhanced in hardware and firmware to provide meaningful non contact measurements of good accuracy. How accurate the camera is over the full range of ambient temperature, I have not tested. Like some thermal camera manufacturers, Hikvision realised that a weakness in many modern budget thermal cameras was the thermal differential between the FFC flag and the temperature sensor used to enter mine it’s surface temperature. An error in this measurement is transferred to ten measurement system and introduces that error into it. Hikvision positioned a small temperature sensor in a ‘garage’ that reps the FFC shutter at a stable temperature away from air currents. The sensor obtains a reasonable measurement of the shutters surface temperature as a result. Nice idea  :-+ As the the accuracy of any master reference for temperature….. that is not known to me at this time. I can say that my test DS-2TP31B easily met the stated specification of measurement accuracy when tested against a Professional Blackbody of known accuracy and emissivity. The permitted error was +/-0.3C between 30C and 45C. My sample unit had an error of +0.1C at 40C in an ambient of 21C and this level of error starts to challenge the accuracy of the Blackbody so an error can be in the cameras measurement, or the Blackbody control loop/deviation etc.

Tim Foo:
Before you open up your UTi260B watch this first

This morning my UTi260B overheated during charging.  I always monitor my USB charging and it went to something like 3.5A!  That's what trigger my interest. 

After disconnecting the charger, I placed the unit in a safer location (outdoors) as a precaution against any possibility of the unit going up in flames.  Some spots are hot to the touch.  The hottest spot is near the (finger) trigger switch is in excess of 54°C, measurement done with an IR Thermometer about 20 min after disconnection.  It took me a bit of time to recompose myself after moving the unit. 

5 hours latter after letting the unit to cool down, as expected that unit wouldn't startup. 

I would now recommend everyone to exercise caution when charging thier UTi260Bs.  It may be sensible to place the unit in some place where any fire dammage can be controlled in case the battery chargging goes wrong.

I will attempt opening the unit up very soon.

Meanwhile I am open to any advice. 


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