Correct Battery Settings For Sunsynk and AM-5's

[Chris888]

Hi all,

Got a new setup which I am still figuring out.

• Sunsynk 8KW
• 3 Hubble AM-5's
• 9 Canadian Solar 545 Panels

The AM-5 specs from the website and what came in the box:

• Capacity: 100 Ah
• Nominal Voltage: 51.2 V
• Equalized Charge 55.2 V
• Charging Voltage 58.4 V
• C Rating: 1.0 C
• Max Continuous charge & discharge current: 100A 

The Sunsynk is picking up the Hubble's, with the following shown under LiBms:

 

I thought that would be that and it would use what the batteries where telling it, however I noticed that my peak charge and discharge from the batteries is only 2100 W.

I guess the battery settings still need to be set. It is currently set at Charge/Discharge 40A, which would explain the 2100 W peak.

 

 

My question is, what are the correct settings?

Batt type

Batt Capacity is 300 Ah

I presume the three batteries in parallel could handle 300A max charge/discharge (What the LiBms also says) but the inverter is only 8KW and from the spec sheet has a 190A max charge/discharge rating. 

So should I go with 150A Charge/Discharge to be on the safe side?

Batt charge

Are the Float/Absorption/Equalization V numbers okay? 

The float V is the same as the Equalized Charge V of the battery specs, but what is Absorption and Equalization V, should those be set to the 58.4V charging voltage?

What are the two Amps numbers on the Batt charge screen? I think from the manual it is the Gen and Grid start voltage. I cant edit the first one, is the second one at 40A alright?

Thanks!

 

Edited October 2, 2022 by Chris888

[P1000]

58.4V is a bit on the high side at 3.65V per cell. I would stick to the voltages that the BMS wanted. You can set your charge and discharge currents to 190A, assuming that the rest of the installation is capable (cable gauge and length as well as fuses). Usually when the BMS is connected, it should override the charge/discharge current settings, but perhaps that is only true when you try to exceed the BMS value.

[Chris888]

@P1000 Thanks. The 58.4V is what Hubble listed as the charging voltage in the little pamphlet that came in the box but will stick with the 57.6V as you suggest.

You reminded me about the fuses. I believe they are 160A. With the three batteries connected with equal length cables to the fuses and then even thicker cable from the fuses to the inverter. But the 160A would then be the limit I suppose. I will double check with the electrician on Monday.

I just upped it to 150A and the Watts charging the battery went up to around 4000 which seems to be what I am getting from the PV at the moment.

   

[GreenFields]

Bearing in mind that with 4.9kW of solar panels, you're not going to be able to supply more than about 95-100A charging from the sun.

The higher charge/discharge of 190A will only be possible when adding power from the grid.

Edited October 2, 2022 by GreenFields

[P1000]

4 minutes ago, Chris888 said:

@P1000 Thanks. The 58.4V is what Hubble listed as the charging voltage in the little pamphlet that came in the box but will stick with the 57.6V as you suggest.  

I would actually go with this:

55.5V. That is closer to what other packs with 16s LFP cells do.

[Chris888]

Thanks @GreenFields, I wanted to ask that.

To work out the max Amps from the panels is it (545W x 9 panels) / operating voltage ?

So 4905 / 41.5 (I think I am looking at the right spec sheet online for these panels) = 118A

But that would be with 100 % efficiency so like you said, 95-100A.

 

[GreenFields]

16 minutes ago, Chris888 said:

Thanks @GreenFields, I wanted to ask that.

To work out the max Amps from the panels is it (545W x 9 panels) / operating voltage ?

So 4905 / 41.5 (I think I am looking at the right spec sheet online for these panels) = 118A

But that would be with 100 % efficiency so like you said, 95-100A.

 

Not quite, it's the available solar power divided by the battery charging voltage. So around 4905/55V or thereabouts at peak of day. So actually a bit closer to 90A max from solar. Just rough thumbsucks not taking weather or inefficiencies into account, just to give an idea.

If you're looking at the panel specs, that's on the input side of the MPPT, not on the output side to the battery, and your 9-panel string would sum to a voltage of around 370V coming into the inverter at around 13A.

Edited October 2, 2022 by GreenFields

[Chris888]

5 minutes ago, P1000 said:

I would actually go with this:

55.5V. That is closer to what other packs with 16s LFP cells do.

Ok, I dropped the Absorption and Equalization V to 55.5V and left the float at 55.2V

Happy to be cautious as I would like to look after the batteries as best as possible. 

[Chris888]

Wasn't sure if I should start a new topic but I was looking at the battery info in Solar Assistant this morning and I see the 1 pack has lower voltage 53.9V at 100% charge. The other two have identical 55.9V.

Is this something I should keep an eye on, a possible issue? Interestingly pack three appears to have a 102.5 Ah capacity which is also odd.

 

 

[Denveronly]

What are the highest voltage i can set on an inverter

what are the highest voltage the inverter can go work with a battery?

i have a two Li-NMC batteries 8s3p batteries together forming 16s3p witch has the most charged voltage of around 66 volts

but i dont want it to be charged so high, i would love to have 62 volts for example to make the battery life longer

i suppose inverter has only 60volts maximum, no other method to make it a bit higher?

i thought about an external charger hooked up to a battery to run at night on offpeak making a bit more juice from 60 the invertor charges to 62 for example. Would that be normal?

[Riff-Raf]

Useful information, thank you. I have a slightly different question related to battery settings... If I have 2 inverters (paralleled and communication properly) and 3 x 200Ah batteries (600Ah in total, joined with a busbar) what the Capacity setting in each inverter should be? 600Ah or 300Ah. Battery settings seem to be inverter specific as you can set different charge current in each inverter. Does the capacity setting accumulate as for the charge current setting or is the setting reflecting total capacity, irrespective of which inverter you set.

I ask this as when you set charge current, it is set per inverter, so if each inverter is setup to 40A, the total charge will be 80A (I have tested and observed this)

Curious to what everyone else is using in their multiple inverter settings.

[HendrikBigChief]

On 2022/10/03 at 10:37 AM, Chris888 said:

Wasn't sure if I should start a new topic but I was looking at the battery info in Solar Assistant this morning and I see the 1 pack has lower voltage 53.9V at 100% charge. The other two have identical 55.9V.

Is this something I should keep an eye on, a possible issue? Interestingly pack three appears to have a 102.5 Ah capacity which is also odd.

 

 

I am guessing each AM-5 is a pack? In that case, they are all connected in parallel? If so, then the one pack having a different voltage is impossible.