Hi I am new to this and i wish to get some advice from the knowledgeable users.

I have a 5 kW Synapse unit with 12 x 330 W  panels and 4 x 225 Ah Varta lead acid batteries connected in series.

in the day I have an excess of power, at night I have to use the grid by early in the morning. the problem with this is that the batteries start charging at 2 amps and I would like them to not charge until the cells come in to charge.

My settings are 01=Sbu,  02 = 60 A,  05 = Use,  06 = Lre,  07 =Tre,  09 = 50,  10 = Avt,  11 = 2,  12 = 47,  13 = 54,  16 = Sbl. Udc,  23 =Bye,  26 = 58.4,  27 =56.8,  29 = 46,

Thanks.

8 hours ago, JRW said:

I have a 5 kW Synapse unit...

My understanding is that these are clones, possibly made my Must Power.

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the batteries start charging at 2 amps and I would like them to not charge until the cells come in to charge.

I assume you mean you don't want utility charging, you'd prefer to wait till PV power is available.

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My settings are ... 16 = Sbl. Udc

I don't know what Sbl.Udc means. Assuming that the Synapse is sufficiently Axpert compatible, setting 16 should have an option similar to the Axpert's OSO (Only SOlar charger source priority). Choose that option to disallow utility charging when the inverter is in bypass.

8 hours ago, JRW said:

26 = 58.4,  27 =56.8

Those figures seem high for lead acid, especially the float setting (setting 27). I would use a maximum of 13.8 x 4 = 55.2 V for setting 27.

You are working your lead acid batteries very hard; consider raising setting 12 by 2 volts or more (raising it one volt will likely make no difference because of setting 29). This will mean using more utility energy (switching to utility earlier in the morning), to extend the life of your battery.

Edited September 22, 20196 yr by Coulomb
Reworded option for setting 16

Thanks Coulomb, I have a bit of a typo in  16 it should be Sbl (solar for batteries first), Udc (disallow utility to charge batteries) however this still has the utility putting in 2 A until the PV power comes on line with the sun. 

There is a setting: Slb (solar for load first), Udc (disallow utility to charge batteries) I could change to this and see what happens, just nervous to change settings the installer made as it may invalidate my warranty.

As for 12 the book recommends 46 Volts the installer put in 47, I understand from you it should be 49 v to prolong battery life.

What do you recommend for 29, the book says 42 V.

Thanks

16 minutes ago, JRW said:

What do you recommend for 29, the book says 42 V.

I would make it 2.0 V less than setting 12. Experiment with 12 and leave the 2 V gap.

I vaguely recall reports that clones don't respect the don't charge from utility setting. So there may not be much you can do.

Thanks will see what happens.