Infrared thermometer

Here's one:

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We used to use them all the time for food temp control. Unless used properly they are very inaccurate. I assume it is a gun type thing you point at the object and pull the trigger, it then gives you the reading. They work off ambient air temp to get the reading of the object so if you have the air conditioning on in the car then take the gun outside into 40 degree heat the reading will be wrong. The ones we used took about half an hour to settle before being accurate again. Same going the other way from hot temp into cold areas. We would often laugh at health inspectors who would drive down with air con on in the car then walk across in 40 degree heat and into our cool room to take a temp with a gun that had just had 3 temp changes in about 30 sec and couldn't work out why in a coolroom at 2 degrees their gun was showing between 25 and 35 degrees on the product. Very handy if you know how to work them to your advantage. We could get a 2 degree reading even though we knew the product was higher. They are very handy units and had never thought of using them for the ideas you have said. I like the idea for brakes or even on shocks after a long drive, sure beats putting your hand on it and finding out it's really hot lol. Would have been handy when we were in Roxy Downs to check temps out there on the ground in 48 degree days, was to hot to touch anything that had been in the sun

Josh

Carl - these things don't actually measure temperature. They measure the amount of heat energy being radiated. That is dependent on both the temperature and the emissivity of the radiator. Emissivity varies widely, so the accuracy as a temperature measuring device is pretty awful.

They are good for comparative measurements such as comparing the temperature of two similar things - your caravan wheels for example. Comparing the temperature of 2 different coloured cars though isn't so good. The cars will absorb different amounts of heat from the sun because of the colour differences and so they will have different temperatures, but emissivity of the 2 colours in the infrared may be quite unpredictable.

Keeping in mind the emissivity issue though, they can be very useful.


John

Or you could hide behind a roadside tree and frighten the .... out of passing motorists.