Battery protection

[flokiisonsolar]

Hi im new to the forum my name is Floki
i need some information around battery protection
i have 4 * 100ah lithium 12v batteries arranged to make 2 * 24v batteries and arranged the 2 24v in parallel. Im running a mpp inverter charger, the model is a 3024gk in the pip- gk serious I have 1400watts pv input and at this stage no grid tied in, as you can imagine i have some heavy loads for this system and require some know how on battery protection. just a note there is integrated protection with this system but only works with Pylontech batteries so i am looking for other options.

 

[John Frum]

I think he means this one https://www.mppsolar.com/v3/pip-gk-series/
1. Use need a BMS capable of handling ~150 amps continous.

A typical commodity fet based bms does cell balancing and has protection circuits.​

The protective functions in include disconnect on cell low/high voltage, pack low/high voltage and over charge/discharge current.​

2. Set the low voltage disconnect and charge parameters correctly on your 3024gk.
3. If you have any other loads you may need a dedicated low voltage disconnect for them.

BatteryProtect - Victron Energy

The BatteryProtect prevents the battery from being damaged. It disconnects the battery from non-essential loads before the battery is fully discharged.

www.victronenergy.com

There are some caveats to using one of these that I will explain if required.​

I bet you will have follow questions, we will deal with those as the come.
Welcome to the forum.

 

[flokiisonsolar]

I think he means this one https://www.mppsolar.com/v3/pip-gk-series/
1. Use need a BMS capable of handling ~150 amps continous.

A typical commodity fet based bms does cell balancing and has protection circuits.​

The protective functions in include disconnect on cell low/high voltage, pack low/high voltage and over charge/discharge current.​

2. Set the low voltage disconnect and charge parameters correctly on your 3024gk.
3. If you have any other loads you may need a dedicated low voltage disconnect for them.

BatteryProtect - Victron Energy

The BatteryProtect prevents the battery from being damaged. It disconnects the battery from non-essential loads before the battery is fully discharged.

www.victronenergy.com

There are some caveats to using one of these that I will explain if required.​

I bet you will have follow questions, we will deal with those as the come.
Welcome to the forum.

yes that is the model mpp i am using
and yes i would love an explanation of the caveats thankyou
there is a single load of AU 240v 2.2kw at 15a will run on 10a that could run at worst case for an hour the system is built to run this device for that per day but have doubled that for autonomy reasons

 

[John Frum]

If your only load is the all in one unit you don't need a battery protect.
If you do have dc load you need to put the battery protect between them and the battery.
They can't be in the charge current path because they can't handle bi-directional current
And they can be in the discharge path of the inverter because they can't handle that much current.
Especially the huge in-rush to charge the capacitors in the all in one unit.

 

[flokiisonsolar]

no dc loads for this setup . so no protect great thanks

 

[John Frum]

no dc loads for this setup . so no protect great thanks

You do have to properly configure the all in one though.
And the bms.

 

[flokiisonsolar]

You do have to properly configure the all in one though.
And the bms.

yes absolutely . i appreciate the info joey. when the system is up and running i will bring over to the show and tell part of the forum

 

[flokiisonsolar]

yes absolutely . i appreciate the info joey. when the system is up and running i will bring over to the show and tell part of the forum . just so we are clear these batteries are not built they are purchased and have the internal bms 1 bms for each 12v pack how does this affect the configuration if at all