Beijer Electronics (formerly QSI Corporation)
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Temperature limits
http://qsiforums.com/viewtopic.php?f=9&t=1710
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Author:  Pierre [ Mon Sep 24, 2007 7:22 am ]
Post subject:  Temperature limits

Hi live up north and many potential applications involve having an HMI installed on systems which are left outside for some time.



Outside means at least -20C. I also have some application where the spec ask for -40C.



Beside these system we see some forestry equipment equipped with touch screens. The are not rate -40C but they are used.



I read the environmental testing of QSI products is performed at -55C!!!



What product can match these applications?

Author:  Anissa Howell [ Mon Sep 24, 2007 2:55 pm ]
Post subject:  Regarding HMI temperature

Depending on the HMI you are looking to use there is different ratings. The average temperature ratings for our terminals is -10 to 60C. The QTERM-G55 does have a lower rating from -20 to 60C. For applications requiring a lower temperature we can offer custom terminals to meet your environmental needs. Please contact sales to further discuss this option.

Author:  Pierre [ Mon Sep 24, 2007 2:58 pm ]
Post subject:  Re: Regarding HMI temperature

anissa.howell (at) qsicorp.nospam.com wrote:
...Please contact sales to further discuss this option.




I certainly will. Thanks



Edit by Jeremy: modified the email address to reduce spam generated by automatic email collection bots.

Author:  Sabian [ Mon Sep 24, 2007 3:55 pm ]
Post subject: 

Here are a few more resources to help determine the right QSI HMI terminal.



Read more about the QTERM-G55 on the QSI Corporation website at:

http://www.qsicorp.com/product/industrial/qterm-g55.php



Or, learn about several of our other rugged graphic and character HMI products on the following page:

http://www.qsicorp.com/product/industrial/



Detailed technical information of our terminals can be found in the product data sheets located on the following page:

http://www.qsicorp.com/support/files/



Thanks

Author:  Pierre [ Thu Sep 27, 2007 8:30 am ]
Post subject: 

To simplify, an example is required.



Say you install an interface inside a truck.



This truck is parked outside during the winter months.



Outside can get as low as -40.



What say you?.



Do all them RPM and Fuel gages display inside the truck are rated -40. I doubt it.



Since you are the expert in this, can you tell me more on the uses vs the ratings.



Thanks

Author:  Ron L. [ Wed Oct 03, 2007 9:40 am ]
Post subject: 

Sounds like you need to look at the storage temperature vs. the running temperature. If your not going to use the terminal until the inside of a vehicle is warmed up then your looking at a different running temperature. For example, the G55 has a running temp of -20 to 60 ?C, but a storage temperature of -40 to 85 ?C. This is what we have thoroughly tested all parts above and below. Does this mean the unit will automatically be damaged at -41? Probably not, but it's more risk as you go beyond the specifications.



You also need to consider that at -40 it would be much too cold for a person to be outside trying to use a terminal.

http://www.ontarioweather.com/winter/sa ... dchill.asp (at least for more than a few minutes)



Just my opinion, for what its worth.

Author:  Pierre [ Wed Oct 03, 2007 9:07 pm ]
Post subject: 

Ron L. wrote:
Sounds like you need to look at the storage temperature vs. the running temperature. If your not going to use the terminal until the inside of a vehicle is warmed up then your looking at a different running temperature. For example, the G55 has a running temp of -20 to 60 ?C, but a storage temperature of -40 to 85 ?C. This is what we have thoroughly tested all parts above and below. Does this mean the unit will automatically be damaged at -41? Probably not, but it's more risk as you go beyond the specifications.



You also need to consider that at -40 it would be much too cold for a person to be outside trying to use a terminal.

http://www.ontarioweather.com/winter/sa ... dchill.asp (at least for more than a few minutes)



Just my opinion, for what its worth.




You understand my point.



Furthermore, in this example, the skid is outside during our winter night. It gets to say ... -36C.



The workers, get there and they "start" the unit. Generators and other equipments. Soon enough, they will need to use the interface to setup some "recipes" for there equipments is run by a PLC and it has some specific guidelines to follow.



At this point the unit is above the -20C but what has happened between the time it was coldest and now.



I usually let my laptop "warm up" for 1 hour when I carry it inside after some time in the cold.



Is there a temperature "shock" value that I must respect?



I know that most of them equipments are working outside there nominal limits, but how do we "spec" a terminal for such harsh conditions?



I have a few project that require some logging equipments to be left in the cold. IT will need to retrieve the data and your interfaces are an excellent choice.



The cold is one thing that appears to be the biggest problem.



I guess that I will need to have "faith", for there is no guaranties in these kind of weather.



My main concern is the liquid crystal freezing and breaking cells, and the weldings of course.



Thanks.



-Pierre



PS:



<<You also need to consider that at -40 it would be much too cold for a person to be outside trying to use a terminal.>>



Are you kidding me! We are in short pants and drinking a cold beer in these kind of weather. Real cold beer :)

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