I.R. non contact Pyrometer suggestions  - Page 1
Forum section: electronics / general

author: calexanian
author_rank: Super Contributor
timestamp: May 19, 2015, 06:55:11 pm
content: Need to get a handheld I.R. pyrometer for annealing glass and I am looking for suggestions. For glass you want about a 5 um detection and will be working in the 600 to 700 Celsius range. Anybody have any favorites? Most of the cheapies do not give the wavelength spec, but for glass you want a shorter wavelength to give a surface temp.

author: mzzj
author_rank: Super Contributor
timestamp: May 19, 2015, 08:41:29 pm
content: Have to say that you have pretty slim choices IF any.My first xhoice would be LAND handhels pyrometer because of their top quality. Best they can offer is Cyclops 390L at 3.9 um. Less than ideal för glass.Cant find anything from the usual suspects ie: LAND, ircon, lumasense, optris, heitronics, Williamson so i am affraid you got the shortest straw this time.Some of the non-portable models are somewhat usable IF you strap external battery Back to them. LAND has a few 5um models and so does lumasense.Id say your best candidates are lumasense in140 with integrated display or in5 with external rs232/4-20ma connected display. Both will need external battery pack and possibly some sort of pistol grip för handheld use. You are probably better of with laser aiming than see-through optics.

author: calexanian
author_rank: Super Contributor
timestamp: May 19, 2015, 10:28:54 pm
content: Thanks. Looks like exactly what I need. I am a little scared about not finding a price for it anywhere and the super expensive looking optics on it. I am going to shoot off an email to them and see how much we are talking about. I will not be surprised if it is well beyond my hobbyist budget, but it does look like exactly what I need. I can see it now. Crowd source me buying a what most likely will be a 1K + pyrometer. Really is it any more silly than some lame art exhibit that nobody will see? Oh wait. A different angle.. Rather than glass for electronics I should claim that I need it to make a political statement art piece. "That's the ticket"

author: CatalinaWOW
author_rank: Super Contributor
timestamp: May 20, 2015, 12:25:46 am
content: By memory this spectral transmission is pretty typical for glass. Don't know how thick the pieces you are working with so I don't know what "surface" might mean, but it seems that 5 micrometers is a longer wavelength than you need. Other than avoiding the quasi-window at 3.1 micrometers it seems you would get a pretty good answer for anything much longer than 2.5 micrometers.Since these things work by comparing the response from two wavebands it seems that if you are really concerned you needed to know the both bands and the transmission slope for the glass you are using to fully understand the answers the instrument gives you.http://www.uqgoptics.com/images/materials_glasses_corning_pyrexBorosilicate_1.gif

author: mzzj
author_rank: Super Contributor
timestamp: May 20, 2015, 06:38:05 am
content: You dont want to go much below 5um cause things get messy.http://blog.lumasenseinc.com/2014/06/17/monitoring-flat-glass-production-temperatures/What comes to prices these are not your cheap.http://blog.lumasenseinc.com/2014/06/17/monitoring-flat-glass-production-temperatures/Land cyclops is easily somewhere 5-8k. Lumasense models probably start from 2-4k

author: calexanian
author_rank: Super Contributor
timestamp: May 20, 2015, 04:36:35 pm
content: Quote from: mzzj on May 20, 2015, 06:38:05 amI am working with relatively thin glass tubing and am mostly interested in the surface temperature for based on that chart i would want something in that 5 to 8 um range like you said. The curves are conveniently flat in that range.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: May 20, 2015, 04:50:40 pm
content: While 3.9 micrometers may view several centimeters into some type of glass, the depth observed will be far less for common glasses. The referenced article provides no units on the transmission curve (either a rate like percent/distance or a thickness for the referenced curves) so it is hard to interpret the sales talk.For borosilicate glass, check this link, which shows several millimeters will be the most really sensed.http://www.edmundoptics.com/optics/windows-diffusers/ultraviolet-uv-infrared-ir-windows/borofloat-borosilicate-windows/1913/For the even more common soda lime glasses several sources, typified by the following, show that about a centimeter will be the maximum depth sensed.http://en.wikipedia.org/wiki/Soda-lime_glassIt all boils down to what you really need to know. If you need the top millimeter you will have to go to longer wavelengths. As you go beyond 5 um you will have to be cautious because the air starts being pretty opaque from a little beyond 5 to about 8 micrometers, leading to other types of errors. You might find the easiest answer somewhere around 4.5 to 5.0. None of that gives you a cheap instrument, but at least you will have a better understanding of what you want.

author: calexanian
author_rank: Super Contributor
timestamp: May 20, 2015, 05:52:52 pm
content: I am only concerned with surface temperatures.

author: calexanian
author_rank: Super Contributor
timestamp: May 22, 2015, 03:20:12 am
content: Just for the heck of it I ordered a relatively inexpensive model off of Amazon. A EnnoLogic eT6500 to be exact. It has a spectral range of 8 to 14 um and it appears to work well. It tracks a thermocouple in the glass within a reasonable amount. Close enough for my use. I am just using it to know when I am above and below annealing point while sealing tubes, and that is just a rough estimate anyways.