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How to verify BMS (Daly) is working?

I like this bms, I am not one to pay extra for a pretty case, just need what works, I like the one will used 72.00 , no black liquid smoke hidden
 
I assume Will one is "Smart Lifepo4 li-ion Lipo LTO Battery Protection Board BMS 48V 72V Bluetooth 20S" on eBay . It provides charge protection. But the balance current is passive and is only 100mA. Ideally 1) active balance, 2) charge protection and 3) bluetooth for a good price. Maybe asking for too much? I am not sure who developed the intellectual property. I assume many copied the IP. Ideally would like to buy from whom developed the IP.
 
Not sure if you can use it in parallel with a DALY BMS with balancing function.

I assume they wouldn't interference with each other. I found another active balancer. It mentioned it will work with other BMS.

"This active balance module is designed with 8S. Multiple strings can be cascaded without limitation on the number of strings. It does not conflict with all BMSs. It only has an active balance function and does not have any management system. It cannot be used as a BMS and a protection board."
 
I found another active balancer. It mentioned it will work with other BMS.
Hmmm, I don't know. Seems to be overpriced for a 8S concept with small LCD.
It has a separate power input for the CPU over a buck converter with separate ground. Seems unnecessary with large battery power available.
Mosfets are very small to drive 4-5 Amps. If very low RDSon, ok. I doubt this small 2 coils can transfer 4.6A and they are the only active components.

I think it's best to go for a decent BMS with display /BT or wifi to see cell V and an active balancer based on coils. The balancer does not need displays as you get these info from the BMS.
I do not say these Broodio's are the best but you can parallel 5 8S units for the same price and have 5A balancing without loose power supplies and much extra needless wires.
 
Hmmm, I don't know. Seems to be overpriced for a 8S concept with small LCD.
It has a separate power input for the CPU over a buck converter with separate ground. Seems unnecessary with large battery power available.
Mosfets are very small to drive 4-5 Amps. If very low RDSon, ok. I doubt this small 2 coils can transfer 4.6A and they are the only active components.

I think it's best to go for a decent BMS with display /BT or wifi to see cell V and an active balancer based on coils. The balancer does not need displays as you get these info from the BMS.
I do not say these Broodio's are the best but you can parallel 5 8S units for the same price and have 5A balancing without loose power supplies and much extra needless wires.
why use a lcd when you have your cell, once its up and running are you going to be looking at that lcd ,hell no,you will now and then look at your cell
 
Finally I have a replacement Daly 16S 120A. I hooked it back on. Now P+ and P- shows essentially the same voltage as the battery overall voltage. P- and B- are only a few mV. Looking good. The old one was shipped back and Daly inspected it and it was burned inside.

However, it doesn't work with my Victron 48v/3000va; it is not inverting through the BMS. P+ and P- only shows 6.5v instead of 53v before connecting to Victron. While trying to investigate and bypass my heavy duty DC switch, I noticed a big current surge and arc to reconnect. It is the charging to the capacitors mentioned by others earlier in the thread. I then shorted BMS P- and B- before connecting to Victron. After Victron is on and inverting, I removed the shorting. Everything appears working fine now. So it appears BMS overcurrent or short protection kicked in if I don't pre-charge the Victron capacitors. The short current protection kicks in at 250A with a delay of 250 micro second.

This is annoy. Every time to restart/reconnect battery, I need to manually short and unshort P- and B-. I don't know if there are better solutions or to automate this process.
 
A discussion about precharging inverter capacitors, including various suggestions on automatic precharge, can be found here
 
Hi Guys, got a Daly 48V 200A 16S Common Port. When my inverter wants to charge the battery it seems the BMS is not allowing the charge through. Measuring at output of inverter I get 57v and when I measure at the pack I get 54v. I have checked that the balance leads are all ok and in correct order. Any ideas?
 
I have checked that the balance leads are all ok and in correct order.
Have you checked the voltage at each pin in your connector?
Pin 1 is negative, work your way from positive pin 2 and see if there is an unusual progression. Voltage should increase about 3.3v as you progress across pins on the connector.
Chances are good you can narrow it down to a single cell. 3v missing likely 1 cell with an issue.
 
Have you checked the voltage at each pin in your connector?
Pin 1 is negative, work your way from positive pin 2 and see if there is an unusual progression. Voltage should increase about 3.3v as you progress across pins on the connector.
Chances are good you can narrow it down to a single cell. 3v missing likely 1 cell with an issue.

Have done that and made sure they are all in correct order and measuring correct voltage.
 
Isn't the Daly BMS the one you need to touch P- to B- the first time to wake it up?
 
It is awake, not the issues I am having. Thanks though.
Is this a brand new BMS ( never used before) or did it use to work and now does not.
Does the BMS work the other way around - will the inverter run off the battery with no charge?
I just had a DOA BMS from Daly, was a seperate port one though. Would not work either way so got a full refund.
Regards
 
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Measuring at output of inverter I get 57v and when I measure at the pack I get 54v.
So the battery voltage (“at the pack”?) is 3 volts less than the charge voltage?
Maybe this is just charging. Does the battery voltage go up after a while?
Do you have a way to check the current to the BMS and from the BMS?

Seems odd if it were a partial failure.
 
check the
So the battery voltage (“at the pack”?) is 3 volts less than the charge voltage?
Maybe this is just charging. Does the battery voltage go up after a while?
Do you have a way to check the current to the BMS and from the BMS?

Seems odd if it were a partial failure.

check the voltage at the charge source.
 
Maybe instead of continuing on this hijacked thread, start a fresh thread with what you have done. There a a few unanswered questions and a LOT of details missing.
I made the mistake of reading 70 posts from 2 different problems that aren’t even related...

Maybe a detailed pic of your setup will reveal something to a sharp eye.
 
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After digging into spec, I do feel the 30mA balancing current is low. My battery is 3.2v 150ah each. I don't see how 30mA is enough for a potentially 60A discharging (48v 3000w) and 30A charging. I just ordered an active BMS with 1.2A balancing current. I hope that is better. My Victron can provide other protection such as temperature, low voltage, over voltage, etc.
What active BMS did you buy and how is it working out?
 
I am with you 100% on everything except this. Looks like maybe an RTFM error.
Step 1 is pretty clear.

FWIW, the Deligreen one page instruction manual is the best I've seen from Alibaba and Aliexpress by a long shot.
I just blew up 2 new Daly controllers by disconnecting in the wrong order. I followed the instructions in connecting in the right order but I didn't pay attention to unplug the other way around. I just wrote Daly an e-mail what they can do about. I'm really pissed of.
I hope they can give me instructions on how to repair myself. I'm not going to send the boards back for repair. Fedex going to cost me as much as the boards.
 
Dang, that is disappointing. I have not heard of problems diaconnecting in the wrong order. Nor do i recall and disconnect instructions.

Do you recall what disconnect caused the problem and how you knew it “blew”?

This is definitely something that needs to be understood.
Daly is blowing it imho.
 
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