Rain Spray Testing

[bigmantony]

Does anyone out there have knowledge and tips on how to create and measure a Rain Spray Test. Our aim is to subject our unit to 1 inch of rain/hour for 2 hrs. How is an inch of rain defined (ie. is there a defined surafce area in which to hold an inch? Is there a droplet size to maintain?) and what would be the best way to create a test set-up.

Tony

 

[IRstuff]

Have you consulted MIL-STD-810?

TTFN

 

[peebee]

Check NEMA standards (NEMA 4, I think?). Also check the European IP (ingress protection) standards which are gaining ever more acceptance in the US.

 

[jraef]

It would be covered under NEMA 3R, which has also now been adopted by UL as a test standard as well. Most electrical enclosure manufacturers have brief descriptions of the test standards, but for detailed descriptions you would need to purchase the standards from NEMA or UL.

http://www.nema.org/index_nema.cfm/1427/B9A5681E-0C0C-4248-A032BE08D6B002B3/

"Venditori de oleum-vipera non vigere excordis populi"

 

[TMD]

You can also refer to IEC 60529. It defines those IPxx ratings you see. It may help.

 

[cuky2000]

There are several “rain tests” standards applicable to electrical enclosure, insulator, motors, electronic equipment, etc.

Please be more specific regarding the application. This will increase the chance for someone to help you.

 

[bigmantony]

Thanks to all for your help. I am working thru the info.
For Cuky2000, we have an IP67 terminal box that will be subjected to all weather conditions and our customer wishes to see that it meets the 1 inch/hr for 2 hrs. We were hoping to attempt the set-up of this test in-house.

 

[cuky2000]

If I understand correct, you are interested to validate degree of protection of the enclosure rated on IP codes. I understand that for an “IP water ingress rating, IEC 60529 does permit the ingress of water, but not in any quantity that would cause harmful effects”.
Probably will be a good idea to check how IEC Std 60525 specifies the test to duplicate this test in your facility.

If the cost and credibility of the test cannot be achieved, consider use a NEMA rated enclosure for this purpose. See the enclose links for reference:

http://www.nema.org/DocUploads/388FCDA2-A544-4191-B2E187CE102C774A/250_IEC60529comparison.pdf

http://www.nema.org/DocUploads/959F0512-1A41-46DF-AC7FA9300AC988F6/FAQ_Enclosure.doc

http://www.espec.com/digest/rain.htm

 

[busbar]

Extreme Long Shot — See “Rain test Nozzle” at

http://www.comm-2000.com/category.a...talogID=ErgonomicsUSA&CategoryID=ULMechanical

 

[pennpoint]

bigmantony
Unless you have the formal testing facilities to do this type of testing yourself, you should send a test sample out to a bonified testing laboratory.
If your need is only one or a small number of units then purchase them from a reputable manufacture and ask for cirtifications they should gladly provide them.
Look at Hoffman, Rittial and others.
You might ask (in a clever way) where your customer came up with his requirements. Thus his answer may very well give you the specification number you need.

Good Luck
pennpoint

 

[TMD]

bigmantony already has an IP67 junction box. This sounds like an additional test the customer wants to see, more for his peace of mind than necessarily complying with a standard. If this is the case, bmt, then you need to come to some agreement with your customer.

 

[bigmantony]

TMD has hit the nail on the head.
Thanks to everyone for their input, So what have I done to resolve my issue.

Well, I placed my unit over a bucket and sprayed it with as fine a spray as I could get from a Homebase Hose and measured the water level after 1hr. It measured 4 inches.
I repeated the process for another hour and this amounts to approx. 8inches of rain over 2hrs.

Conclusion: Our unit still operates after 2hrs of spray (4inches) So we shall assume that our customers spec of 1 inch of rain/hr for 2hrs will not produce any issues.

We shall present this case to our customer.