Pylontech and Kodak inverter floating charge

[Adeptus Mechanicus]

Does this look correct? Replaced my old Mecer and AGM setup yesterday and viewing SolarAssistant with the new equipment now for the first time.

• Kodak OG6.2 Twin
• 2x Pylontech UP5000's
• There is comms between the batteries and inverter
• Inverter has the Pylontech battery program set.

Haven't been on battery since about 6am this morning. Voltage cycles between 53.2v and 50.2v basically over the course of an hour.

Does this look like normal lithium battery floating charge behavior?

 

[leon.davibe]

Yes the lithium lifep04 pushes voltage up to 3.55v -3.65v per cell(53.25-54.7)to charge full and then the voltage comes to resting voltage of about 3.35v(50.25v)

ie both voltages are regarded as full one for charging and one for resting

The battery is configured with 15cells

This settling takes 1-1.5hrs on my shoto

naturally if loadshedding hits just as it is fully charged that superficial high voltage 53.2v drops very very quickly to 50.2v

Edit on the graph it seems it cycle in and out of charge cycle
ie i assume it does not ask you to set the voltages

imo it isn't needed to permanently cycle like this

if you change the float voktage to 50.2 it will leave the battery to rest and not do the steep voltage cycle all the time

 

[leon.davibe]

So what currently happens is it charges to 53.2 and the allows it to settle but since the float is set that high when the battery comes down to resting voltage

It drops enough under the float to trigger another charge cycle

Make the float 50.2 to 50.5v

A high float helps if you have panels and want to make better use of surplus power

But in a battery backup only the lower float will allow the batteries to rest

 

[TheChamp]

Does this look correct? Replaced my old Mecer and AGM setup yesterday and viewing SolarAssistant with the new equipment now for the first time.

• Kodak OG6.2 Twin
• 2x Pylontech UP5000's
• There is comms between the batteries and inverter
• Inverter has the Pylontech battery program set.

Haven't been on battery since about 6am this morning. Voltage cycles between 53.2v and 50.2v basically over the course of an hour.

Does this look like normal lithium battery floating charge behavior?

View attachment 1520363
View attachment 1520365

Max charge current looks too low, if Kodak is the same as Axperts that should be the total sum of both grid and solar.

 

[Adeptus Mechanicus]

Max charge current looks too low, if Kodak is the same as Axperts that should be the total sum of both grid and solar.

Yeah, not sure if perhaps it autoselects that when on the Pylontech program, but I did try and set it to 60A via SolarAssistant and the inverter itself and it just defaults back to 10A total

 

[Adeptus Mechanicus]

Yes the lithium lifep04 pushes voltage up to 3.55v -3.65v per cell(53.25-54.7)to charge full and then the voltage comes to resting voltage of about 3.35v(50.25v)

ie both voltages are regarded as full one for charging and one for resting

The battery is configured with 15cells

This takes 1-1.5hrs on my shoto

naturally if loadshedding hits just as it is fully charged that superficial high voltage 53.2v drops very very quickly to 50.2v

Edit on the graph it seems it cycle in and out of charge cycle
ie i assume it does not ask you to set the voltages

imo it isn't needed to permanently cycle like this

if you change the float voktage to 50.2 it will leave the battery to rest and not do the steep voltage cycle all the time

Nope. It's using the built in Pylontech charging profile selected within the inverter menu, so no manual setting of voltages

 

[leon.davibe]

Max charge current looks too low, if Kodak is the same as Axperts that should be the total sum of both grid and solar.

The charging amps is too low because it is full already

And the charging cycle has been triggered again because the resting voltage is to low below float which trigers a charge cycle on a full battery

So just as it Is ramping it pushes into the steep voktage and then stops charging and goes into float state which with a true lithium means not supplying an actual float which is the case and it settles to 50.2v

if it was supplying float it would not settle and stay at 53.2v

Edit
The behaviour of letting it settle is better if it just did not cycle into charging again

 

[leon.davibe]

You could try the USE setting

Change the voltages and see behaviour

And then change to lithium setting again and see if the voltages stay same as set or changes

If it keeps the float low bonus

Edit my device allows me to change the voltages under lithium setting not a growatt though

Maybe because i don't have comms

 

[Adeptus Mechanicus]

Max charge current looks too low, if Kodak is the same as Axperts that should be the total sum of both grid and solar.

Confirmed that this does change dynamically by itself.