BMS leeks shutting down

[Dazza66]

Hi, I have a LifePO4 304ah system with a 250 Daly BMS and 415watt solar panel.
My problem is it keeps shutting down. All my BMS parameters are as speced. Have to keep rebooting the system. Any solutions greatly appreciated. Thanks, Daz.

 

[DIYrich]

One 415 watt solar panel isn't going to charge a 304ah battery.

 

[Dazza66]

What do you recommend?

 

[crossy]

@Dazza66 what's your battery voltage, which charge controller are you using?

 

[Dazza66]

@Dazza66 what's your battery voltage, which charge controller are you using?

13.6 volts.

 

[740GLE]

What’s your load?

I charge my DIY 12v 460ah JBD battery with a 30w east facing panel and 50w west facing. I have zero load (except when we’re at camp) and are able to put in about 250whr a day. The battery hits 14.1v after about 5 days after a weekends use.

 

[Alkaline]

Hi, I have a LifePO4 304ah system with a 250 Daly BMS

Problem diagnosed! You Have a Daly BMS...

 

[crossy]

OK your 30A charge controller maxes out at 390W of PV at 12V so you are slightly over-panelled for the controller, probably not an issue.

On a nice day your panel will probably give you 1200Wh ish (very much dependent upon weather, location, panel orientation).

304Ah @ 12V is about 3600Wh.

So, if I've done my sums right you will need 3 days to charge your pack if there's no other load.

What's your load?

I suggest you may be needing more panels and a meatier charge controller

Do you have access to check the voltage of each cell? Could be out of balance.

Start off by leaving it with no load for a few days (just the panel and charge controller connected), or, if you have a suitable charger and power charge the pack from the mains.

 

[Dazza66]

OK your 30A charge controller maxes out at 390W of PV at 12V so you are slightly over-panelled for the controller, probably not an issue.

On a nice day your panel will probably give you 1200Wh ish (very much dependent upon weather, location, panel orientation).

304Ah @ 12V is about 3600Wh.

So, if I've done my sums right you will need 3 days to charge your pack if there's no other load.

What's your load?

I suggest you may be needing more panels and a meatier charge controller

Do you have access to check the voltage of each cell? Could be out of balance.

Start off by leaving it with no load for a few days (just the panel and charge controller connected), or, if you have a suitable charger and power charge the pack from the mains.

I ran 2 fridges. 7amps each and a couple of led lights.
Balance of batteries are 0.001v.

 

[Dazza66]

Problem diagnosed! You Have a Daly BMS...

So your says the Daly BMS is rubbish. What BMS should I use?

 

[740GLE]

JBD and JK seem quality these days.

I’ve been running my JBD 4S 200a for about a year without a hiccup on 2P 230ah eve cells.

Granted my load is very minimal 90% of the time, but haven’t had issues with 300-400w peak demand.

 

[740GLE]

I ran 2 fridges. 7amps each and a couple of led lights.
Balance of batteries are 0.001v.

That’s a lot of constant load.

I’d say triple the storage and triple the PV and you might be close to sustaining that 24-7 during peak Solar months.

 

[Brainwater]

One 415 watt solar panel isn't going to charge a 304ah battery.

This is simply not true.

 

[crossy]

I ran 2 fridges. 7amps each and a couple of led lights.
Balance of batteries are 0.001v.

I'm assuming these are 12V appliances / lights?

Is there any indication of actual energy consumption for the fridges over a 24-hour period. One hopes they're not going to be running 7A constantly, are they??

If we assume a 30% duty cycle (that may be waaaay off, hence my asking if there's any manufacturer's data) then that's about 7*12*24/3 Watt hours per day per fridge = 1,344 Watt hours per 24 hour period just for the fridges!

 

[DIYrich]

This is simply not true.

I suppose if you live in Alaska and can get 9 hours of intense solar each day during the summer.

 

[Dazza66]

I'm assuming these are 12V appliances / lights?

Is there any indication of actual energy consumption for the fridges over a 24-hour period. One hopes they're not going to be running 7A constantly, are they??

If we assume a 30% duty cycle (that may be waaaay off, hence my asking if there's any manufacturer's data) then that's about 7*12*24/3 Watt hours per day per fridge = 1,344 Watt hours per 24 hour period just for the fridges!

All 12 volt appliances.
Not sure of consumption of the fridges.

 

[Dazza66]

That’s a lot of constant load.

I’d say triple the storage and triple the PV and you might be close to sustaining that 24-7 during peak Solar months.

That’s a lot of constant load.

I’d say triple the storage and triple the PV and you might be close to sustaining that 24-7 during peak Solar months.

That’s not constant load.
Not sure on how to measure consumption over a 24 hr period.

 

[740GLE]

Smart shunt.

We’ve all determined the load is greater than the supply. Until you obtain a smart shunt to track said usage, the cheapest solution is more PV. Until you are able to track your consumption it’ll just be a guesstimate as how much PV.

 

[crossy]

Smart shunt.

We’ve all determined the load is greater than the supply. Until you obtain a smart shunt to track said usage, the cheapest solution is more PV. Until you are able to track your consumption it’ll just be a guesstimate as how much PV.

And more charge controller, his existing unit is already over-panelled

 

[crossy]

Not sure of consumption of the fridges.

Anything in the manufacturer's data? Let us know the manufacturer and type, some are very clever with Mr Google.