signalab bms wiring help needed

[radad]

I know only enough electrically to be very dangerous. This is my first ebike build. I'd hate to burn out my new bms. Googling turned up nothing useful to me to wire this thing up. Its a signalab bms 14 series li-ion pcb. I been fooling with this schematic for 2 days and i'm still not sure of the wiring . Is this schematic correct?

 

[999zip999]

Ping has the info on his website.

 

[dogman dan]

Only thing I would do different, would be to run the - to the bms before the watts up. Connect the watts up to the main negative discharge wire after the bms.

 

[Ypedal]

if you have a 14 cell pack, your BMS should have 13 balance wires.

Start from cell 1 , at the most POSITIVE end, and work your way to the most netagive end of the pack..

cell 14 ( most negative end ) connects to Batt- on the BMS.

your controller positive, goes directly to the cell1 pack positive.. and the controller negative goes to the BMS P-

 

[radad]

ping does have some info on these(the most I found anywhere), but not a wiring diagram. I have a extensive backround in building/OCing computers going back to the 90's. I have never seen such a lack of info on any electronics device/PCB ever. No instructions, no wiring diagram, no mfg website, nothing useful on google.
There must be someone who knows. And there must be many more who would like to know. Lets get this schematic corrected (if necessary) so others may know too!
Maybe i'm stupid but this schematic tells me next to nothing

 

[Ypedal]

the above is NOT correct... it shows 13 cell with 14 balance wires... this BMS does not work like that.

 

[radad]

Only thing I would do different, would be to run the - to the bms before the watts up. Connect the watts up to the main negative discharge wire after the bms.

So its correct other than the bms placement? Cause i'd like to wire this thing like right now?

 

[dnmun]

if you have the watt meter in the B- lead then it will cause an added delta voltage to be added to the cell voltage of cell #1 so the pack will hit LVC early under load.

if this were a BMS where there is a separate sense wire lead to the bottom of #1 then you could use the watt meter in the B- lead. but the signalab uses the B- lead for the bottom of #1.

 

[Ypedal]

 

[radad]

OK I get her done! Nothing blew up
The LED's are starting to light up. I am one happy camper right now. I took a ride last night before wiring the BMS on the highly unbalanced pack @ 57.4v The battery pack put out 1007 watts and 23.22 amps according to the watts-up, got up to 27.5 mph very quickly. I've had a couple 1/2 mile runs without BMS, Soon as it charges and balances i'm having a nice night ride 2-5 miles.

GNG mid drive 1000w stock controller
58v 14s6p samsung 18650-26 15ah
Watts-up
Specialized Mtb bike

 

[radad]

3 LED's lit up and charger turned off. Whats going on? Is it finished charging?

 

[Rassy]

3 LED's lit up and charger turned off. Whats going on? Is it finished charging?

Not finished yet. At least one of the sub parallel packs has reached HVC and the charger doesn't turn off but goes into balance mode. You mentioned that the pack was out of balance so it may take a while for it to be fully charged and balanced. Of course you can check individual cell (sub parallel pack) voltages to see how out of balance things still are, but under these conditions I normally unplug the charger from the battery for a few minutes until the lit LEDs drain down their cells and go out. Then I plug in the charger again, until it goes into balance mode, then repeat. All this does is speed up the time it takes to get the full battery balanced (i.e. all LEDs on).

 

[dogman dan]

Yep, do the normal break in/ balancing procedure. Charge till all lights are on, however long it may take. Then do a 3-6 very short rides, followed by charging till all lights are on. Hopefully by the third one, all the lights begin to light up at closer to the same time.

 

[dnmun]

no it is not right. you don't know anything about the signalab BMS. the B- lead is the sense wire for the bottom of #1.

 

[radad]

the above is NOT correct... it shows 13 cell with 14 balance wires... this BMS does not work like that.

hello , all 13series battery should be with 14 wires. 1S battery is with 2 wires, one for positive, the other one for negative. 2S with 3 wires. The rest may be deduced by analogy. The drawing is provided by exprienced engineer. It is right. These wires function are balance and voltage test.

Yea that makes sense. My signalab 14s has on the connector 1 red,12 gray and 1 black. Now i'm even more confused then ever. Wheres the 15th wire? Neg end of pack don't need it? Last (neg.) cell not charging is at 3.96v.

I wired my BMS exactly as shown in my schematic on first post except I didn't wire in the watts up yet. I'm a very analytical SOB and also very inpatient, I'm about ready to take out the BMS or should I say take out the BS. The pack is more unbalanced with the BMS then when I started. Two parallel cells are at 4.23v (red leds lit up) two other are at 4.20 1 led blinking 1 not lit at all. 1 cell at 3.96v the rest between 4.05-4.11v. Before wiring the BS all cells were at 4.05-4.19v closer together in voltage then after 6 hours charging with BMS. WTF! If I can't find documentation on this device I'm dumping it. Is this device only made for battery pack manufacturer's? not intended for the public therefore no documentation?
Why is charging above 4.2?
What does the blinking led mean?
Why is my charger turning off with only a few led lit?
When exactly does balance function occur? when charger turns off?
WHERE IS THE DOCUMENTATION???
Why did I buy this BS knowing the lack of documentation?
http://www.ebay.com/itm/BMS-PCB-for-50-4V-14S-Li-Ion-Battery-Pack-50A-10A-limit-with-Balance-Function-/150980944671?ssPageName=ADME:L:OU:US:3160

 

[999zip999]

The cells are best if charge and balance before you install the bms so the bms can keep them in balance. That is the first step. The bms works best if start on a balanced pack to keep a pack balance and used as a magic board that we dream about. You can leave it on the charger and let the bms balance the pack over time on the charger and all led's should light up. I have taken a small flashlight bulb to help the high cell bleed down just like the bms does. What cells are you using ?

 

[radad]

The cells are best if charge and balance before you install the bms so the bms can keep them in balance. That is the first step. The bms works best if start on a balanced pack to keep a pack balance and a magic board that we dream about.

Well i'm sure your right, but all its doing for me is unbalancing and taking a hell of a long time to do it. in over 7 hours the 3 leds that were lit are now blinking. there are just to many variables involved. I still not even sure its the right bms for my pack. It says 14s but only 50.4v thats only 3.6v each. Just more confusion at every turn.
Installing this BMS is like going to a grateful dead concert and swallowing anything that someone hands you!
I DO appreciate all your help but seems like I could have taken a 4.2v charger and balanced it myself manually faster and fifty eight dollars cheaper. Please don't tell me this thing takes like 2 days to balance/charge cause it would be totally useless to me then.

 

[dnmun]

it will take 2 days to balance.

 

[999zip999]

An unbalance pack. After you balance the pack it should keep balanced if cells are match. Skipping the first step of precharging is what is costing you time on the charger for the bms to bleed down the highest cell ( cells ). Get the flashlight blub out and discharge the high cell or cells just like the bms does. I have done this while it's on the charger and the charger turned on to fill the low cells. Yes skipping steps takes more time. But after all leds light up and a couple of light discharge and recharge cycles it should be a lot easier to charge and balance.

Sorry dropped some words early.

 

[Rassy]

If it is the wrong BMS for your pack we can't really help you much, but, it's hard to follow what you are doing. You said the LEDs that were lit are now blinking. That is normal if you have unplugged your charger from the battery. Then if you plug the charger in again those three LEDs should light up very quickly. Leave it plugged in until the charger goes to balance mode and then check the individual voltages again, they should be moving up. See my previous post here for a technique to speed up the balancing process without using individual external loads, etc.

Let us know what is happening. Good Luck.

 

[Ypedal]

is your pack lifepo4 2.0 - 3.6v .... or Li-Mn/lipo/etc.. 3.0v - 4.2v

the led's show when the resistors are bleeding power, slow blink is low duty cycle .. when the led is fully lit and not blinking it's burning off as much energy as it can .

once the pack is in perfect balance, the charge cycle will be shorter, but save yourself and the BMS a huge time and use a 2 amp charger to fully charge all the cells, then hook up the bms.

 

[999zip999]

Need some info about the cells and the battery pack. The nut's and bolts.

 

[dnmun]

The cells are best if charge and balance before you install the bms so the bms can keep them in balance. That is the first step. The bms works best if start on a balanced pack to keep a pack balance and a magic board that we dream about.

Well i'm sure your right, but all its doing for me is unbalancing and taking a hell of a long time to do it. in over 7 hours the 3 leds that were lit are now blinking. there are just to many variables involved. I still not even sure its the right bms for my pack. It says 14s but only 50.4v thats only 3.6v each. Just more confusion at every turn.
Installing this BMS is like going to a grateful dead concert and swallowing anything that someone hands you!
I DO appreciate all your help but seems like I could have taken a 4.2v charger and balanced it myself manually faster and fifty eight dollars cheaper. Please don't tell me this thing takes like 2 days to balance/charge cause it would be totally useless to me then.

since you have now been instructed to remove the BMS and charge it without the BMS to protect the battery you will need to monitor the cell voltages of the cells that are now fully charged. the BMS is shutting off the charge because some of the cells are fully charged already so when you remove the BMS in order to make it charge more than the cells that are already fully charged will be overcharged and damaged.

you need to know when they are charged so much more that the voltage exceeds 4.3V since lipo will not withstand overcharging at that level.

 

[radad]

over 14 hours today charging. 6 led lit, its slowww . but seems to be working.

Heres my setup:
GNG mid drive 1000w stock controller 48v/22amp
Watts-up
Specialized Mtb bike
homemade 58v 14series 6parallel samsung 18650-26a, 2600ma each cell 84 cells total. should be around 15ah and 30amps max.
cell data sheet http://www.batteryonestop.com/baotongusa/products/datasheets/li-ion/Samsung-SDI-ICR18650-26A.pdf
Bms seller/info http://www.ebay.com/itm/BMS-PCB-for-50-4V-14S-Li-Ion-Battery-Pack-50A-10A-limit-with-Balance-Function-/150980944671?ssPageName=ADME:L:OU:US:3160
Charger http://em3ev.com/store/index.php?route=product/product&path=37&product_id=120

 

[Rassy]

Glad it's working for you. It should be obvious now why the cells should have been balanced before installing the BMS. Once it goes into balance mode just a tiny trickle of current is being sent to the low cells and hence the long time required to balance the pack.

Once you get over this hump I think you will really like the Signalab BMS. Those LEDs let you see that the pack is balanced at the end of every charge so there is no reason you should have it drift out of balance, at least not until some cells have gone bad and its time for a new battery anyway. I've had batteries with other BMSs, including one from BMSBattery where the BMS was buried within the final wrapping. At the current time I only purchase and/or recommend Ping batteries, mostly because of the V2.5 Signalab BMS he uses. Of course I'm talking about systems where a LiFePO4 battery is adequate.