I'm curious to know how the Outback GT/GV series inverters Sell mode actually works? I did read that it needs first go through a daily charge cycle (Bulk/Float) before it can start to sell back. That is somewhat clear, but how the actual selling mode works is not?

In my case I'm interested in using solar panels with MX-60 charging the batteries, and then selling the extra power back to the grid with GT/GV. Once the charging cycle has completed and selling started, how does the GT/GV determine how much (an at what power level) to sell?

Ideally (what I think...) the inverter should monitor the battery voltage and keep it constant at the "sell" level. If the power increases from PV, the sell power will increase, and if PV power decrease, the sell power will decrease as well, just simply by trying to "regulate" the battery voltage at constant level. Or is this sell mode just a "dumb sell flat out" until a battery voltage has dropped to a level needing a new charge cycle? I have not been able to find out this detail from forums (here or Outback) or Outback documentation... (But I haven't really searched that hard yet...)

So how does it work, really?

You have a programmable sell voltage, the GTFX simply clamps the battery bank to that voltage by selling energy to the grid. Its NOT a daily recharge thing, it requires a single full charge cycle form power-up or line disturbance and then will regulate to the selected sell voltage

OK. I got the GTFX3048 working with my MX60 and it is selling back to the grid...

I do not have HUB, so the two can not "talk" to each others. I have set this up on outdoor and do use the RTS (temp sensor) that is connected to the MX60. The GTFX sell voltage is set to 51.8V if I recall correctly. It appear to work, but of course the temperature compensation does not.

What I'm planning is that if I buy second RTS and hook it up to the GTFX, does the Sell voltage get compensated based on the battery temperature? (I think it should... but just making sure before investing to another RTS.) Of course I could buy HUB but that is almost $200 investment... the RTS is only few bucks.

EDIT: Purchased second RTS from eBay for 11 bucks... I'll let you know how it works (a week later or so).

EDIT2: Got the second RTS installed to FX. It appear the SellRE voltage is NOT temperature compensated. Is that something someone can confirm?