Coal PIle Temperature

[shantanu@india]

Hi,
Looking for a IR device/camera to measure the temperature of a coal pile in a thermal power plant to alert in case of spontaneous combustion.
The device should be able to read in the range of 0-200 degC with an accuracy of +/- 2 degC.
Only criteria...cost!! Fluke gave me a price of 25000 dollars!!

[top204]

I bought one about 12 years ago for £20 from Maplins, and they are now quite common and not very expensive, except if you buy a Fluke type. Fluke are good, but not that good, and they have always been stupidly expensive. :-) I bought a fluke multi-meter in the mid-1990s when I was repairing satellite receivers for Sky, and it was good, but not that good and did the same job as a mult-meter a 10th of its price. It also broke down about 6 years after I bought it and could not be repaired due to the silly buttons they had used on it, so it was a total waste of money. My Maplins multi-meter has been with me now for about 15 years and does the job well, and it only cost about £20.

Here is an IR Thermocouple meter for about £90, but they do come less expensive:

https://thermometer.co.uk/infrared-thermometers/527-raytemp-8-infrared-thermometer-with-type-k-thermocouple-socket.html

You can buy an Infrared Thermocouple component and make your own meter, but the component is usually more expensive than the complete meter.

[JonW]

The accuracy will be a problem with any low cost sensor.  Module

datasheet

[RGV250]

Hi,
How about a Melexis sensor  https://www.melexis.com/en/product/MLX90614/Digital-Plug-Play-Infrared-Thermometer-TO-Can
https://www.sparkfun.com/products/9570
https://learn.sparkfun.com/tutorials/mlx90614-ir-thermometer-hookup-guide/all

Bob

[top204]

Even on Ebay, with its greedy sellers, a ready made unit with a 1.5 degree accuracy is only approx £10.00:

Digital Infrared Thermometer Non-Contact Pyrometer

So they are guaranteed to be less expensive elsewhere.

Looking at the price of the IR thermocouple components, they are approx £9 to £10 on their own, or close to £20 if bought from one of the rip-off companies such as Adafruit or Sparkfun, so it is better to buy a ready made handheld unit for general temperature measurements, or buy a ready made unit and take out its components for a DIY project or data managing project.

When such high temperatures are to be measured for general purpose usage, is high accuracy really needed? i.e. Does it matter if the object is 198 degrees C or 200 degrees C? :-)

I wish I had been brought up to be a rip-off merchant like the people I have worked for most of my life, and feel no sympathy for the people I would have ripped off. :-(

[shantanu@india]

Sorry to be so late in replying friends!! Plain forgot that I posed this question to my learned colleagues...
Thanks for your responses Les , Bob , John.
Les handheld devices are not what I am looking for. I need an automated solution where the camera/pyrometer connects to a processor/Single board computer via an Ethernet port where an image analysis software analyses the IR image & generates a textual colour temperature chart to be uploaded to the database. This camera would be physically mounted on a coal stacker/reclaimer machine & would be focussed on the coal pile that is being stacked or reclaimed.
Bob , I am actively thinking of buying a Melexis product for evaluation. My constraint is the distance. The stacker reclaimer sits about 4/5 meters above the coal pile. Don't know the accuracy of these sensors at a distance.