Good day. I have a 3kw mecer sol-i-ax-3vp inverter. With 2x 100ah lead acid batteries.  We use it for beating loadsheding.  Just the basic, light's alarm and internet. My previous batteries died on me and I  recently got these.  I also installed a 540w solar panel to help get the batteries charged during loadsheding at day time. My question is what is the best setting for the inverter to make best use of the pannel and to preserve the batteries for loadsheding at night.  It only has 3 options, Solar first, SBU and Utility  and then for charging it gives Solar first, Utility, Utility and solar and lastly only Solar.

13 minutes ago, Quins said:

Good day. I have a 3kw mecer sol-i-ax-3vp inverter. With 2x 100ah lead acid batteries.  We use it for beating loadsheding.  Just the basic, light's alarm and internet. My previous batteries died on me and I  recently got these.  I also installed a 540w solar panel to help get the batteries charged during loadsheding at day time. My question is what is the best setting for the inverter to make best use of the pannel and to preserve the batteries for loadsheding at night.  It only has 3 options, Solar first, SBU and Utility  and then for charging it gives Solar first, Utility, Utility and solar and lastly only Solar.

I remains a problem if you want to make use of solar as much as you can but also ensure you have enough battery power to beat LS. 

Charging from solar only you can save a bit on grid use but that might mean when there is not enough sunshine the batteries might not get fully charged. Getting lead acid fully charged can take more than 12hrs.

Thus charging from solar and grid provides the best chance of getting enough power to charge the batteries and to be in a position to be ready for LS. 

Using solar 1st again reduces the power to charge at the expense of using less grid power. SBU or UTIL gives a better chance of having battery power when there is LS. 

It all depends on how much of the 1200Wh the batteries can provide during LS. Lead acid can only provide 1200Wh when discharged to 50% in order for the batteries to make it past the about 9 month life. 

Ok thanks.  I will giv3those settings a go. Speaking of 50% sharge. The DC cut of voltage. When I change it up and down it effects the battery capacity as displayed on the inverter. I understand that I should only discharge the batteries to 50%. But if I set the Low Dc cut of voltage to 24v  I barly have an hour. The load is at 100 and some thing Watts. I should have 12 mor or less. I set the floating charge to 27.5v but any recommendations on the other settings? 

 

15 minutes ago, Quins said:

Ok thanks.  I will giv3those settings a go. Speaking of 50% sharge. The DC cut of voltage. When I change it up and down it effects the battery capacity as displayed on the inverter. I understand that I should only discharge the batteries to 50%. But if I set the Low Dc cut of voltage to 24v  I barly have an hour. The load is at 100 and some thing Watts. I should have 12 mor or less. I set the floating charge to 27.5v but any recommendations on the other settings? 

 

You did not indicate what the bulk charge level is. Set it to 29V. If charged to a lower level you will indeed experience a much shorter run time. 

You can use cut out at 23.6V as 24V is the level at 50% under no load but the inverter will normally be under load when it cuts out. 

Edited June 3, 20233 yr by Scorp007

50% is resting percentage . 

So I would let the Battery rest for 10 minutes before charging ofter loads to get an idea what your battery percent really is .

The higher the constant load the lower volts you can set for shut down volts