Re: [RE-wrenches] Inverter temperature (was Electrolytic Caps vs. Thin Film Caps)

[Allan Sindelar]

Steve, My understanding is that wind chill by definition only affects living things. From Wikipedia: "The rate of heat loss by a surface through convection depends on the wind speed above that surface: the faster the wind speed, the more readily the surface cools. For inanimate objects, the effect of wind chill is to reduce any warmer objects to the ambient temperature more quickly. It cannot, however, reduce the temperature of these objects below the ambient temperature, no matter how great the wind velocity." So in a high wind an inverter will cool more quickly until it reaches ambient temperature, but it won't be any warmer inside a enclosure. If the inverter is producing enough internal heat through inefficiency, an enclosure could slow the rate of heat loss enough to warm surrounding internal components a bit more. But this wouldn't have any effect on the inverter in your New Jersey example, as the inverter can't produce heat until it's in operation. Could there be another explanation? Thanks, Allan Allan Sindelar al...@positiveenergysolar.com NABCEP Certified Photovoltaic Installer NABCEP Certified Technical Sales Professional New Mexico EE98J Journeyman Electrician Positive Energy, Inc. 3201 Calle Marie Santa Fe, New Mexico 87507 505 424-1112 www.positiveenergysolar.com On 1/19/2012 4:01 PM, Steve Jefferson wrote: Afternoon Wrenches, All SMA models in the US are rated for -25C (-13F). Canadian models are rated for both -25C and -40C.   I highly recommend if installing in areas with any extreme temperatures, to build an enclosure around the units. Sometimes with the wind chill factor temps can be quite more than just the ambient temp. Installing in a conditioned building is always ideal though.   I talked with an installer in New Jersey who had a system that was not turning on until late morning. He went out with in early morning with and took the temperature from one of the caps and it was about -30 F. We figured out that this extreme cold was caused by the north to south wind hitting the inverter, mounted on the backside of the ground mount. He built a little wall to protect from the wind, and the problem was solved.   SMA America, LLC Steve Jefferson Sr. Technical Service Specialist, Sunny Family 6020 West Oaks Blvd, Suite 300 Rocklin, CA 95765 - 3714 U.S.A. Tel:  +1 916 625 0870 Fax: +1 916 624-2445 Service Line +1 877 697 6283 (Toll Free) Email: steve.jeffer...@sma-america.com www.SMA-America.com

_______________________________________________
List sponsored by Home Power magazine

List Address: RE-wrenches@lists.re-wrenches.org

Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org

List rules & etiquette:
www.re-wrenches.org/etiquette.htm

Check out participant bios:
www.members.re-wrenches.org