Why doesn't my daly smart bms start balancing?

[Lt.Dan]

There is a trick to turn on the balancer all the time:

There is a hidden parameter available in sinowealth called ‘Balance open current’ that must be changed to 0 (or even negative) if you want to balance at low or zero current. It was set to 30mA on mine. Changing this to 0 will give you maximum balance time. This parameter kind of acts like a balance enable switch.

Unfortunately the balance on Daly is a very small current (the advertised value of 30-35mA appears to be a peak current, with an average current much less), so the more time you can spend balancing the better….. With this setting, the Daly will even balance after high voltage disconnect before the mosfet turns back on, which will maximize your balance time.

I use ‘Balance voltage’ parameter of 3.4V – meaning that the balance will turn off below this voltage and all is well. I use a ‘balance voltage difference’ of .005V.

While you are in there set ‘DfilterCur’ to 200mA or something reasonable. Any current below this value will be changed to (and displayed as) 0. Note that this parameter is the primary reason why the ‘Balance open current’ acts like an on-off switch for balance.

Why Daly would ship their BMS with these settings is a mystery to me.

I will definitely be trying this! Thank you!

 

[2BZ2Ranch]

This is an interesting thread.
So, I can turn the balancing off (Thanks to @Sharky722 - set balance start voltage to above the hvd) and use
Active Balancing - OR - balance all the time via sinowealth and set BOC to zero.
? What rationale would one use to choose one over the other?

 

[John Frum]

This is an interesting thread.
So, I can turn the balancing off (Thanks to @Sharky722 - set balance start voltage to above the hvd) and use
Active Balancing - OR - balance all the time via sinowealth and set BOC to zero.
? What rationale would one use to choose one over the other?

I've already given my opinion earlier in the thread so I won't repeat myself.

 

[2BZ2Ranch]

@smoothJoey , #8,,, my apologies,,,,

 

[halibut58]

This is an interesting thread.
So, I can turn the balancing off (Thanks to @Sharky722 - set balance start voltage to above the hvd) and use
Active Balancing - OR - balance all the time via sinowealth and set BOC to zero.
? What rationale would one use to choose one over the other?

Here is my understanding:
-The balancing on the Daly is always passive. That just means it drains a tiny bit of current out of high cells only. That is ok but slllllooooowwww.
-To enable (activate) the balance several conditions must be met (each of which can turn balance off or on...)
1. the cell voltage must be less than 'balance start voltage' (BSV) (i.e. cell voltage above 3.4V will enable balance)
2. the difference between cells must be greater that 'balance voltage difference' (BVD)- say .005V
3. the current must be greater or equal to 'balance open current' (BOC). I set this to 0mA, meaning it balances when charging or no current.

There is a "feature' in these BMS that will set the current to zero if it is below a certain level (‘DfilterCur’). This is due to the accuracy at low currents where many low cost BMS have a bit of a problem, not just the Daly, and even more expensive (better?) units. On my Daly the mistake they made at the factory is that they set this threshold to 2 or 3A. And then they set the BOC to 30mA -meaning the balance did not work below 2 or 3 A! That is the effect of 2 parameters interacting. And as a bonus it only shows currents above 2 or 3A (ouch) on bluetooth.

To turn off balancing, you can do one or more of:
-set BSV to high (say 3.7V)
or -set BVD to something large (say 2V? never tried it)
or -set BOC to current larger than you will ever use (impractical but possible?)

Note:
Some people say you should only balance when charging, but I found that for the higher voltages (above 3.4V) there is no issue balancing with no charging current (even with charger disconnected). The Daly idle current is about 15mA, meaning you will always drain a bit on your battery anyhow, and with the balancer active, the balancing will just add a bit to that drain until the voltage drops below 3.4V (for the over cells). That usually takes something like a day. So that way your balancer can get in some decent time. And time is your friend....

Just a heads up if you ever actually try to figure out what the actual balance current is - it is significantly less than even the weak 30mA spec (something like 6mA average). If you attempt to calculate how long your balancer will take, it will take a lot longer than the spec indicates. This is for both my 100a Dalys. That is the reason why time is your friend with your Daly....

 

[Dutchboy69]

The DALY balancing sucks only does it when charging. I am running 2 48VDC 400 Ah Lithium packs each with its own BMS and active balancer.
The packs before the active balancers would start to drift. I connected a 16S active balancer to each pack in within a day the cells in each pack were balanced. .004 of a volt. Now when charging (inverters can put out 45 amps each) they do drift but the active balancers bring the cells back in order within an hour after the charge is done. They do not drift enough to trip the BMS when charging as the cells are of good quality.
Narada 80ah cells parallel 5 to make a 400 ah cell of 3.2 volts 400ah.

 

[Lt.Dan]

There is a trick to turn on the balancer all the time:

There is a hidden parameter available in sinowealth called ‘Balance open current’ that must be changed to 0 (or even negative) if you want to balance at low or zero current. It was set to 30mA on mine. Changing this to 0 will give you maximum balance time. This parameter kind of acts like a balance enable switch.

Unfortunately the balance on Daly is a very small current (the advertised value of 30-35mA appears to be a peak current, with an average current much less), so the more time you can spend balancing the better….. With this setting, the Daly will even balance after high voltage disconnect before the mosfet turns back on, which will maximize your balance time.

I use ‘Balance voltage’ parameter of 3.4V – meaning that the balance will turn off below this voltage and all is well. I use a ‘balance voltage difference’ of .005V.

While you are in there set ‘DfilterCur’ to 200mA or something reasonable. Any current below this value will be changed to (and displayed as) 0. Note that this parameter is the primary reason why the ‘Balance open current’ acts like an on-off switch for balance.

Why Daly would ship their BMS with these settings is a mystery to me.

After fiddling with this software for quite some time, I read that Sinowealth does not work with batteries larger than 10s. So it will not work with my 16s BMS. Everything just returns 0's in the results.

I can open it with "DalyBMSMonitor" that I found. But it has no "Balance open current" settings, and frankly is no different from the Andriod/iOS apps. Pitiful.