australia:irthermometer
Table of Contents
infrared thermometers
see also:
- I don't sell any of these nor do I receive any remuneration if you buy them, and I have not personally reviewed all of them, they are listed here to give you perspective
Introduction
- infrared thermometers allow you to ascertain the temperature of objects from a distance by measuring the infrared wavelength of light that they are emitting
- this page only discusses those devices which just give a temperature readout rather than a visual heat map and temperature read out - for these see thermal imaging cameras
- the temperature range will vary depending upon the device:
- those designed for human foreheads will only go to 50degC in general even in “object” mode but are far more accurate than most industrial devices
- human skin has an emissivity of 0.95-0.99 but these forehead thermometers use an emissivity of around 0.78 in human mode to give a reading that approximates oral temperatures
- when set to object mode they presumably use an emissivity of 0.95
- medium temperature “industrial” / BBQ models may have a temperature limit of around 500degC
- high temperature industrial ones will have a wide range of temperature from minus 50degC to 1500degC
- industrial ones usually have:
- 1 or 2 lasers to help aim the device
- ability to set the emissivity from 0.1 to 1.0
- a narrow “angle of view” which is measured as distance to spot (D:S) ratio
- wider ones for general use are 16:1, more industrial very high temp usage are 30:1 allowing you to stand 3m away to measure a 10cm area
- 12:1 models are generally best at 36cm distances from objects
- newer sensors have a faster response time of under 250msec, older ones are 500msec
- more expensive ones will be drop proof to 3m and water-resistant
- industrial IR thermometers are NOT good for assessing fevers as they are NOT sufficiently accurate, even the better ones have an accuracy of only ±1.8°C and that assumes you have ascertained the correct emissivity value!
- in fact they are NOT very accurate for most of your needs of ambient temperature measurements where a +/- 2 degC error when measuring something at 20degC can give a measure anywhere from 18-22degC - probably NOT useful
- where they are great is for measuring very hot temperatures and a few degrees out does not make any difference for most uses.
- the device will need to have the emissivity set for the type of material you are measuring otherwise you will get inaccurate results
- for many objects, their emissivity CHANGES significantly with major changes in temperature!
- SOME devices have a FIXED emissivity of 0.95 which you cannot change limiting its versatility greatly!
- they are however adequate for most non-reflective non-metal surfaces, and painted or non-reflective coated metals
- eg. Klein IR1 as emissivity set to 0.95; HoldPeak HP-960C for cooking;
- to ascertain the emissivity you can either:
- use a table look up
- for most materials, emissivity is the opposite of reflectivity
- unoxidised aluminium = 0.02-0.03 depending on temp
- oxidised aluminium = 0.11-0.19 depending on temp
- polished stainless steel = 0.07
- matte stainless steel / aluminium = 0.2-0.3
- unoxidised cast iron = 0.21
- gravel = 0.28
- water = 0.67
- moderately oxidised cast iron = 0.65-0.78 depending upon temp (strongly oxidised = 0.95)
- snow = 0.82-0.89
- glass = 0.92-0.94
- most non-reflective non-metals = 0.95
- cooking oil = 0.95
- ice = 0.95
- measure it by comparing with contact probe:
- heat a target object well above room temperature and measure it by a trusted contact probe and via IR making sure the IR is not detecting the probe itself (best to remove the probe)
- ensure there are no hot objects nearby that could cause reflections that interfere with the measurement
- The surroundings of the object should have the same temperature as the sensor ie. don't measure it inside an oven
- Adjust the emissivity setting on the IR sensor until it measures the same temperature as the contact probe
- measure it by painting part of it matte black:
- paint part of it with matte black BBQ paint
- heat the object as above, measure the painted area at emissivity 0.95 then adjust emissivity whilst measuring non-painted area to get the same temperature reading.
wide temperature range devices for really hot objects at a distance
- HoldPeak HP-1800C
- -50~1800℃ (-58~3272°F)
- 50:1 D:S thus designed for being around 5m or more from object
- HoldPeak HP-1500C
- -58°F - 2732°F (-50°C - 1500°C）at +/- 2% accuracy above 0degC (+/- 4°C below 0°C), resolution: 0.1°C under 1000°C, 1°C over 1000°C
- <250msec response time
- 30:1 D:S
- 30cm = 1cm spot; 1.5m 20-30cm spot; 3m 10cm spot; 9m 30cm spot; 15m 50cm spot
- dual LED flashlights
- dual laser beams
- backlight; 9V battery, 160g, 7.6 x 3.75 x 2.5 inch
- HP-1500APP version gives Bluetooth smartphone control $AU84
- older model, HP-1420C has older sensor and measures to 1420degC
- HoldPeak HP-985B
- as for HoldPeak HP-1500C however:
- -50℃～1360℃(-58℉～2480℉) accuracy ±3°C
- 16:1 D:S makes it more useful for cooking than a 30:1 model as you only need to be 1.6m for a 10cm spot not 3m away, 0.7m gives a 4cm spot, 2m gives a 13cm spot;
- UT303D
- -32°C – 1250°C; 250ms with single spot laser; 30:1 D:S; 9V or can be powered by USB; 322g;
- $AU188
reduced temperature range devices
- Mestek IR01D
- -50℃~800℃, ±1.5% + 2℃; 12:1; 500msec; 2xAAA;
- color screen, ambient temp thermometer (takes 30min to adjust) and humidity meter; $AU40
- FLUKE 62 MAX+ IR
- -30 C to 650 C (-22 F to 1202 F); 12:1;
- 300ms
- FLUKE 62 MAX IR
- -30°C to 500°C; 10:1 D:S; 500msec;
- 3m drop proof; IP54; AA battery; 255g; $AU268
- UT309C
- -35 ~ 650°C ( -31 ~ 1202°F) ≥0°C: ±1.8°C or ±1.8% of reading
- 12:1 D:S
- dual laser; 250ms response;
- 3m drop proof; IP65; 32mm × 29mm LCD; 292g; 189mm × 118mm × 55mm; 9V battery; $AU119
- HP-985C-APP
- as for HoldPeak HP-985B however:
- -50 C to 800 C ( -58 to 14720 F ) accuracy 0-100°C = ±2°C and above 100°C = ±3°C
- 500msec response
- Bluetooth
- HoldPeak HP 980D-APP
- -50℃ to 550℃(-58 to1022℉)
- 500msec response
- Klein IR5
- -30° to 400°C; 2m drop proof; dual laser; 9V battery;
Dual IR and probe devices
- Klein IR10
- -40°C to 650°C; 20:1 D:S; dual lasers; 3m drop proof; IP54; 9V battery;
- Klein IR07
- -40°C to 300°C; 8:1 D:S;
- calculates the differential temperature (T1-T2) for both IR and probe temperatures
devices designed for cooking
- Inkbird Ink-IFT01
- -50℃ to 550℃ at ±2°C accuracy; 500ms; 12:1 DS; 1 laser; 3cm spot at 36cm; 9V battery; $AU33
- HoldPeak HP-960C
- designed for holding 3-4cm from food or cooking surface but will not be adequate for wood-fired oven pizzas which need 450degC
- -30℃~275℃ (-22~527℉)
- read out within 0.5sec; no laser pointer; preset emissivity;
- finger-sized 3.3x 0.6×0.8in (84x16x20mm); Weight:30g; Two 1.5V(LR-44) button batteries;
australia/irthermometer.txt · Last modified: 2022/07/28 19:32 by gary1