I notice that the spec sheets for the FX2000 Inverter and the MX60 charge controller both state that the units will handle operating temperatures up to 60C (140F - this sounds great) but that de-rating occurs above 25C (77F - this does not sound so great).

Sooo... about how much de-rating should you assume in a typical southern US summer temperature (such as 40C/104F)? Or a more extreme case (e.g. lower desert area @ 50C/122F)?

I am most interested in the FX2000 but it would be good to know the Outback position on both, especially since 77F seems really low...

Thanks! [img]images/smiles/icon_biggrin.gif[/img]

Both the FX inverter and MX controller are designed to tolerate hot environments (we called ourselves "OutBack" after all).

The official listing ratings on the products are at 25C/77F. This is mostly done as it is the easiest and fastest way to complete the testing for the certification (which also means less money spent with the test lab). We have left considerable margin in both of the designs to allow for operation at higher ambient temperatures however. I will get the information and post it here as soon as I can.

One interesting thing we have done on the FX inverter is to not temperature derate the surge capacity at high temperatures. Most inverters advertise high surge ratings which are only achieved from a cold start condition. So a pump for example will run when you test it on a cool day but you get called back because it won't run in the summer. With the FX series the surge rating is kept conservative when cool so that you can be assured it will operate the load even under high ambient temperature conditions.

Hi Chris,

Any word on the specifics for de-rating stats? Or is the info still TBD (i.e. are you guys working on it in the lab)?

<BLOCKQUOTE><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><HR>Originally posted by Christopher Freitas:
... (snip)
I will get the information and post it here as soon as I can.
(snip)
<HR></BLOCKQUOTE>

Thanks! [img]images/smiles/icon_biggrin.gif[/img]
-Roger

Here is the information on the performance of the OutBack products at high ambient temperatures.

The derating on the FX2000 is -20VA for each degree Celcius above 25 degrees Celcuis.

So for a OutBack inverter operating at an ambient temperature of 40C - the maximum continuous power is decreased by 300VA (15C x -20VA/C) to 1700VA from the original 2000VA rating.

We also have published the data on the short term performance of the FX2000 - here it is:

5 minutes 3500VA
15 minute 3000VA
30 minute 2500VA
Continuous 2000VA

These perfomance numbers assume a "cold" start in a 25C ambient environment.

The derating curve for the MX60 is still being determined - the 60 amp rating has been field tested in high ambients (~35C) without causing any derating. We need to operate it at full power in a thermal chamber to find out when it actually does start to limit. It will depend somewhat on the amount of voltage step down it is handling as this has a small impact on the efficiency. [img]images/smiles/icon_cool.gif[/img]

Chris,

Oops, I just realized I didn't reply to this thread after your update appeared, although I did see it and really appreciate it!

Looks great, thanks to you & the team for making the data available!

-Roger [img]images/smiles/icon_biggrin.gif[/img]