Nema 4 HMI - indoor use only?

[RMore]

I have noticed that many HMI have a Nema rating of Mena 4/4X (indoor use only)

Does anyone have any guesses as to what the constraints are that limit the HMI to being used only indoors?

 

[Rson]

I have noticed that many HMI have a Nema rating of Mena 4/4X (indoor use only)

Does anyone have any guesses as to what the constraints are that limit the HMI to being used only indoors?

I think most of it has to do with being in sunlight. You can wash them down, but I don't think the screens are made made to be outside in the sun.

There are HMI covers you can get for outdoor HMI's with a prop stick that will give a Nema 4/4X outdoor rating. I've used them on several jobs now and they seem to work fairly well.

https://www.hammfg.com/electrical/products/accessories/pjhmi

Edit: Also be aware many HMI models don't work in the freezing cold either!

 

[James Mcquade]

+1,
this is what i have been told from AB tech support.
the touchscreen film will not last in sunlight, we use protective covers as suggested and they have been in place for 5 years.
james

 

[BryanG]

Also, the outdoor versions generally have an extended temperature range, things can get very hot in the sun. The PBCs are often coated to protect them against moisture. But, perhaps most importantly, the backlights are much brighter so that you can see the screen when the sun shines. Typical indoor screen brightness is 350 - 400 nits / cd/m^2, outdoor screens are in the range of 800 to 1000 nits / cd/m^2. It makes a huge difference. We were at a sight where they were using a competitors machine which used a standard HMI. Bubba had added a couple of screws so that he could drape a sack over the screen, and he would regularly disappear under the sack to operate the machine.

 

[Puddle]

Does anyone have any guesses as to what the constraints are that limit the HMI to being used only indoors?

Having asked The Google, I'd go off the IP rating.


https://en.wikipedia.org/wiki/IP_Code


The comparison table shows that NEMA 4/4X is equivalent to IP44, IP65 or IP66. I'd never use an IP44 component outdoors, but IP66 is rated again water jets and therefore fine for outside. IP67 is rated for immersion.



This is a Simatic outdoor Comfort panel and page 3 says that it's IP66 at the front or NEMA 4, which means it's fine to use outside based on the IP rating, but not the NEMA rating.



https://mall.industry.siemens.com/t...caller=EGH&mlfbs=6AV21240QC130AX0&language=en

 

[Rson]

Having asked The Google, I'd go off the IP rating.


https://en.wikipedia.org/wiki/IP_Code


The comparison table shows that NEMA 4/4X is equivalent to IP44, IP65 or IP66. I'd never use an IP44 component outdoors, but IP66 is rated again water jets and therefore fine for outside. IP67 is rated for immersion.



This is a Simatic outdoor Comfort panel and page 3 says that it's IP66 at the front or NEMA 4, which means it's fine to use outside based on the IP rating, but not the NEMA rating.



https://mall.industry.siemens.com/t...caller=EGH&mlfbs=6AV21240QC130AX0&language=en

Most HMIs carry both an IP and NEMA rating. Those HMIs rated 4/4x are typically rated IP65 or IP66. I still wouldn't use it outdoors unless it had a cover on it or the screen was specifically made for outdoor use.