Larry, If you need a bigger diversion than a Tristar can handle, you can use a relay controlled by the auxiliary output of a charge control or inverter and have the relay close when the voltage is 0.2 volts higher than the diversion voltage. You can switch on a load that is 50 to 75 % of the diversion load and let the diversion controller do the fine tuning. Let me know if that does not make sense. David Katz
----- Original Message ----- From: Larry Crutcher, Starlight Solar Power Systems [mailto:la...@starlightsolar.com] Sent: Tuesday, November 29, 2011 05:35 PM To: RE-wrenches <re-wrenches@lists.re-wrenches.org> Subject: [RE-wrenches] Diversion load for AC coupled system Hello Wrenches, I would like some advice on diversion load control of 3800 watts of PV solar. The battery bank is 48 volts and the battery inverter is the MS4448PAE. This will AC couple with a grid tied inverter during an outage. Magnum Energy recommends the addition of a dump load for safe battery voltage control. The customer may leave the home unattended for weeks so I am looking for reliability here. Quality, as well. A pair of Tristar 60's should be suitable for the 3.8kW output but I haven't been able to find a load that is sized for this job. I welcome any advice on this subject. Thanks in advance. Larry Crutcher Starlight Solar Power Systems _______________________________________________ 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 _______________________________________________ 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