<font face="arial" size="4">I went over all of this with the folks @ Outback a couple of years ago when I was amazed to discover my home system's "3600" watt inverter (GVFX3648), was not able to sell 3600 watts for any length of time without overheating. At the time, others on the wrench list commented it is actually more like a 2800 watt inverter (unless it is running in a freezer).<br><br>The "air temp" <u>IS</u> the transformer temperature.<br><br>Shutdown for the transformer is @ 38 counts (250.7 degrees F)<br>Shutdown for cap/fet boards is @ 79 counts (194.2 degrees F)<br>(see attached chart for temp counts to degree F/C conversion)<br><br>Selling 2.7 kW (75% loaded) on a hot summer day (ambient of 92F in the power building) before modifications I typically saw:<br>
Trans = 43<br>
Fet = 143<br>
Cap = 147<br><br>Selling only 2.7 kW (75% loaded) on a hot summer day (ambient of 92F in the power building) after modifications I typically see:<br>
Trans = 50 (still way too hot to touch the case above the xmfr)<br>
Fet= 155<br>
Cap = 169<br><br>Modifications included: <br>
- Removing the "bug screens" above and below the fet/cap boards<br>
- Adding another fan on top of the internal fan's air intake.<br><br>My typical efficiency (PV input wattage versus actual selling wattage) runs ~87%.<br><br>Hope this is helpful.<br><br>Todd<br><br><br><br><br>On Friday, February 26, 2010 9:59am, "Michael Welch" <michael.welch@re-wrenches.org> said:<br><br>> <br>> >From: jfh@greenhousepc.com<br>> ><br>> >toddcory at finestplanet.com writes:<br>> >> How high have the temp counts on your transformer gotten?<br>> ><br>> >I'd pay closer attention to the FET and CAP temperatures. The<br>> >transformer sensor measures air temperature<br>> >and the other two get hotter, faster.<br>> ><br>> >> > I have a test coming up for a client where I'm going to try and get<br>> a<br>> >> > pair of GVFX3648's to sell 7.2KW.<br>> >><br>> >> My home system's GVFX3648 maxes out at around 2.8 to 2.9 kW @ 80 degrees<br>> F. If I push it harder, it<br>> >> overheats. While they are rated at "3600 watts", they cannot do this<br>> continuously with ambient temps<br>> >> above ~40 F.<br>> ><br>> >I'll be monitoring the FET, CAP and AIR temperatures while they are<br>> >selling. If the temperatures get<br>> >out of hand, the software will back off the amount of sell power.<br>> >--<br>> >Julie Haugh<br>> >Senior Design Engineer<br>> >greenHouse Computers, LLC // jfh at greenhousepc.com // greenHousePC on<br>> >Skype<br>> <br>> _______________________________________________<br>> List sponsored by Home Power magazine<br>> <br>> List Address: RE-wrenches@lists.re-wrenches.org<br>> <br>> Options & settings:<br>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org<br>> <br>> List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org<br>> <br>> List rules & etiquette:<br>> www.re-wrenches.org/etiquette.htm<br>> <br>> Check out participant bios:<br>> www.members.re-wrenches.org<br>> <br>> <br></font>