Portable Temperature Simulator/Calibrator

[esware]

I am wondering if anyone can comment about the Xitron 2000MN Themocouple Simulator/Calibrator? I found this model listed in a T.O. for calibration of Honeywell UDC Controllers.
We have a requirement for a portable thermocouple simulator to perform calibrations per AMS2750D. This is an Aerospace Material Specification that requires for us to use an intrument with accuracy of +/- 1 degree F or 0.1% of reading. The biggest problem that I have found is finding an instrument that will meet this spec fo Type S thermocouples. I looked at the specs for the Xitron and see that is meets these requirements but want to know if anyone can comment about whether it will really meet these specs? I tried one instrument with the listed specs meeting the requirement but in real life, would not meet these specs. I hope to not repeat this mistake.

Comments or suggestions? 

[metrologygeek]

We support fairly large quantities of Xitrons as well as Ectrons, and while the Xitrons have excellent straight DC specs, thermocouple measurement and simulation specs aren't quite as good when you consider cold junction compensation. Over the years, we've had reliability and accuracy problems with the cold junction compensation, and many of ours are red lined for external cold junction compensation only. The Ectron 1140A, though, has better specs and has been bulletproof so far, and Ectron has been very helpful in providing firmware that provides command set compatibility with older models so we didn't have to rewrite our legacy software routines. I'd take a look at them before you buy.

[MIRCS]

Xitrons are great in a lab enviroment.  On site, they suck. 

[esware]

Thanks for the input. Any suggestions for on-site instruments? We currently use Omega CL-25 but the specs for S Type thermocouples is not good enough. We need something portable to take to the furnaces that we need to calibrate. The environment that these will be used in is not where I want to take a bench model instrument like I believe the Ectron is. Any thoughts?

[spanishfly25]

I normaly use the fluke 725 for all my TC calibrations, but is only plus/minus 1.8 degrees for type R and S TCs. we do calibrated some furnaces that use Type R TCs. but the furnace is plus and minus 10 degrees. the range of a type R TC is so big that 1.8 degrees is like 0.1%

[USMCPMEL]

I use an Omega CL23A and a Fluke 744 but neither one of those is good enough to work in your situation...

[jimmyc]

are you reading a thermocouple or simulating? or both?

[esware]

The primary need is for simulation. It is possible that the need to measure will be required, but immediate need is to simulate type S thermocouple to calibrate the controllers used on the furnaces. The accuracy requirements are tough to find acceptable portable equipment. If we have to go with a bench type instrument then we will but would really like to find a portable instrument. Any ideas?

[USMCPMEL]

How accurate do you need it to be?

[USMCPMEL]

I am looking at you original post and saw the accuracy of your unit is +/-1.8 and the item you are trying to calibrate is +/- 10. That meets the 4 to 1 accuracy requirement so I am a little confused as to what your problem is? I did find this handheld unit fairly cheap made by Omega that is +/- .25 Degrees C or +/-.5 degrees F I think that would work very well for you. Not sure how reliable it is or anything I have no experience whatsoever with that instrument.

[MIRCS]

Altek 422

[jimmyc]

can't you use a mV source and the S temp chart then?  that is all a thermocouple calibrator does anyway.