First full day of sun with new system, but batteries not charging

[740GLE]

Getting ssoc from Victron connect via mk3 to MPII

MPII as in Multiplus 2? Do you have a Victron smart shunt? Multiplus need a shunt to properly measure SOC.

Also voltage based SOC is pointless.

Watts don’t disappear, either it’s being used, going into the battery, or burning something down.

 

[HalfBaked]

it looks like the bulk charge is trying to get to 57.59VDC. Is this the correct setting?

It looks like you are trying to charge 48v 500AH(24kwh) with 1155watts? Seems under sized to me.

My rudementary understanding of this is the batteries can charge at 0.5 Charge rate or 250amps. I think 0.20 charge rate is preferred(100 amps). What I am seeing is 16.5 amps.

Yes you're right, my batteries are under paneled and my SCC is overpanelled. I'm working on that as funds permit. But I don't need to charge it all in one day as they last around 3 days

 

[HalfBaked]

They have to be, the screenshot shows it (unless you have a load) That is why I asked what the load was. If the load is greater than the PV generation, you will have a net loss.

Understood. But the load was 350ish for 3hrs while the SCC was showing 1300ish gain, yet this resulted in a net loss. So I'm guessing the PV is not going to the batteries.

 

[HalfBaked]

MPII as in Multiplus 2? Do you have a Victron smart shunt? Multiplus need a shunt to properly measure SOC.

Also voltage based SOC is pointless.

Watts don’t disappear, either it’s being used, going into the battery, or burning something down.

Yes Multiplus 2. I also have the smartshunt, they don't talk tho, no ve network.

I just don't know where they're going. Seems the busbars are eating it.

 

[timselectric]

If your clamp meter is showing amps going into the bus bar. Clamp onto the other wires on the bus bar to see where it's going.

 

[740GLE]

Is the clamp meter set to AC or DC when you are doing you’re readings?

 

[740GLE]

Yes Multiplus 2. I also have the smartshunt, they don't talk tho, no ve network.

I just don't know where they're going. Seems the busbars are eating it.

Can you post some pictures of your connections/bus bar/shunt?

 

[Madcodger]

If you have all Victron equipment, they definitely CAN "talk": and you don't need a Cerbo GX. Google "Venus on Raspberry Pi". There are multiple sites, including Victron itself, that will help you create a low-cost monitoring system.

 

[Texas-Mark]

I just don't know where they're going. Seems the busbars are eating it.

If you are measuring it, and nothing is getting overly warm, there are only two places current can go, the battery or the load.

 

[HalfBaked]

Thanks everyone for the tips. I'm troubleshooting this at the same time as I'm adding new arrays, ending up with about 5500w, will know more in a couple days and then update.

 

[HalfBaked]

So this is what's throwing me:

One image is VC via mk3 from MPII.
The other image is a screenshot of VC via smartshunt Bluetooth to phone.

They were taken a few seconds apart. They have similar voltages, but SOC varies wildly. Meanwhile, if the MPII thinks SOC is too low, it will shut down. How can I tell the MPII to adjust SOC?

 

[MisterSandals]

One image is VC via mk3 from MPII.
The other image is a screenshot of VC via smartshunt Bluetooth to phone.

It looks like the Morningstar screen in the first pic is charging at 17A. Does this go thru your shunt? I need to look back from the beginning but this stands out to me.

 

[HalfBaked]

It looks like the Morningstar screen in the first pic is charging at 17A. Does this go thru your shunt? I need to look back from the beginning but this stands out to me.

Yes, I have traced the amps coming from the SCC to the busbars, then evenly split to the batteries. At first I thought I wasn't getting the amps, but it's these mismatched socs that are confusing me, especially when the inverter shuts down because it thinks the battery is too low.

 

[HalfBaked]

Amps passing shunt

 

[740GLE]

Can you provide a image of the interconnections of the elements?

 

[HalfBaked]

What I've got

 

[740GLE]

What are the settings of the MPII?

If it’s hitting low voltage disconnect under load is that hitting 48v at the terminals of the MPII?

 

[HalfBaked]

No, it's showing voltage in the 50s, but telling me that SOC is 10% under mild load 250ish watts

 

[740GLE]

VE.Bus Smart dongle - Victron Energy

Communicate system information straight to your smart phone using the VE.Bus Smart dongle, with battery temperature-and-voltage sensing. Find a dealer now.

www.victronenergy.com

Also this will allow your MPII talk to your shut over Bluetooth without needing a cerbo.

 

[HalfBaked]

MP2 settings