Programming Conext 6848
Goal, Program inverter to not sell to grid but feed subpanel. Automatically recharge from grid only as last resort. Grid will always burn a bit of power (about 1.5 kwh/day which costs about 17 cents a day) so the inverter can track grid AC cycling and keep grid qualified. This is pretty much required if I want automatic grid backup during low battery conditions.
Context 6848 made June 2015 so up to date firmware with Context battery monitor feeding 395 amp/hr battery bank using 4500 watt solar array. Charge controller is a Magnum PT-100 that does not communicate with charge controller. I've read the manuals and learned some here and this is my current programming. Circuits wired to subpanel including well pump and clothes washer average 11 kw/hr draw per day. I intend to run dishwasher and clothes washer on sunny days further minimizing drain on this smaller battery bank. What do I need to do to optimize this setup?
Load Shave on with 0 Load Shave Amps, Sell is enabled with 0 Max Amps Sell, Grid Support is Enabled.
Grid Supply set at 49.2v so Grid will come on stopping almost all of the drain on my batteries below 65% to protect batteries; so far this is working well with the batteries draining less than 20% most nights. This hopefully will allow the next sunny day to recharge batteries avoiding using power from the grid to recharge batteries. Inverter Recharge set at 47.5% (35% battery remaining) to avoid nuisance trips when the well comes on. If inverter does charge from the grid charger is set at 16% power which gives me a slow c/20 charge rate if the grid is used in hopes the sun will show up to finish the charge cycle minimizing grid power recharging.
Low Battery Cut Out (LBCO) voltage is set at 47.2 (28% battery) to protect batteries in a grid down situation. LBCO Delay is set at 15 seconds once again to minimize the chances of the well pump coming on while something else is on and tripping LBCO.
With the exception of paying an electrician to wire the subpanel (I would like to keep my insurance company happy) I installed this system myself. I may eventually pay for the permit and electrician to wire me up to sell back to the grid but with this smaller system I'm not sure it's worth while financially.
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