Hi my name is Sam I have just install 2 5kva Mecer Axpert inverters with 24 335w panels and 3 pylontech S3000 batteries. I an in the process of setting it up and would like to know how do I set is up for priority solar so that in the day it runs on the panels and then at night switches to the batteries. When the batteries get flat it uses the grid as a last resort.

Any advice

regards

Sam

4 hours ago, Gwedge said:

how do I set is up for priority solar so that

Setting 01 (Output source priority) to SbU, and setting 16 (Charger source priority) to SNU, or OSO if you never want utility charging.

Make sure that settings 12 (back to utility voltage) and 13 (back to battery) are set to sensible levels. These depend on your battery, your tolerance for using utility power, and whether you are using something like ICC to automatically switch for you.

Hi I do still want to use utility charging but want it as a last resort. I am using 3 x S3000 pylontech batteries and my inverters are set as follows.

Program 02    70A

Program 05    USE

Program 12    48V

Program 13    51V

Program 26    53.2V

Program 29    46V

What I am getting now when the utility goes down, which it often does, is an error 04 low batter even when I have 4 or more green lights on. I am not sure if I am charging the batteries up enough although all indication are that I am or at least almost fully charged. I would also appreciate your suggestion on what a sensible value would be for option 12 and 13 would be.

 

 

 

20 hours ago, Gwedge said:

Hi I do still want to use utility charging but want it as a last resort.

Program 29    46V

What I am getting now when the utility goes down, which it often does, is an error 04 low batter even when I have 4 or more green lights on.

You want to avoid the battery low warning if at all possible. It means the inverter thinks the battery is "weak", meaning it will switch to line mode. Once it's declared weak, it should stop being weak at an undocumented 4.0 V (for factory firmware) above the battery low cutoff voltage (program/setting 29). So I'd reduce setting 29 until this stops.

It is declared weak when the battery voltage reaches 2.0 V (for factory firmware) above setting 29. It might be worth checking the battery voltage calibration (use a good multimeter), and the battery cables and fuses / breakers for voltage drops under load. Are your battery cables perhaps too thin? They should be at least 35 mm².

20 hours ago, Gwedge said:

I would also appreciate your suggestion on what a sensible value would be for option 12 and 13 would be.

I consider those to be "adjust on test" values. It depends on many factors, chiefly your loads, and how tolerant you are for using utility power. You could start by reducing them both by 1 V.

Another undocumented gotcha: if your battery low cutoff setting (setting 29) isn't at least 2.0 V below the back to utility setting (setting 12), then the effective back to utility setting is the battery low cutoff setting (setting 29) plus 2.0 V. So if you decide to try reducing setting 12 to 47 V, you should reduce setting 29 to at most 45.0 V, or it will have no effect.

Thank you I will adjust when I get home as program 12 is 50 and 29 is 45 and see what the net effect is.

the battery cable at all from pylon tech and look rather thick, I would say are 35mm. I currently do not have a fuss or MCB on the batteries as I can't get either in Zim at the moment, is there another way to check the batteries?