BMS Battery 5-13s Smart BMS connections
- Thread starter jbalat
- Start date
jbalat
10 kW
Ok this is what I think I need to do to get this working..
Of course hook up the balance leads as well which i did not show in the photo..
I'm a bit unsure of the Battery + wire.. Is it wired before or after the switch ? If it is after the switch then do I need the switch on to charge ? I assume i need to move the fuse to the motor positive lead now ?
Appreciate your help..
Here is a link to bms info page. http://www.bmsbattery.com/smart/330-lifepo4lithium-ion-smart-bms-for-513-cells-in-series.html
Of course hook up the balance leads as well which i did not show in the photo..
I'm a bit unsure of the Battery + wire.. Is it wired before or after the switch ? If it is after the switch then do I need the switch on to charge ? I assume i need to move the fuse to the motor positive lead now ?
Appreciate your help..
Here is a link to bms info page. http://www.bmsbattery.com/smart/330-lifepo4lithium-ion-smart-bms-for-513-cells-in-series.html
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jbalat
10 kW
dnmun
1 PW
you do not need a fuse if you have a BMS that functions. you should put a fuse in the charging lead at the battery. just large enuff to handle the charging current.
you should not carry the full battery current to the BMS, just the circuit current to drive the BMS.
you don't show a picture of the controller, just the motor so i assume you mean controller.
that BMS will not handle the current the lipo packs can push imo. it would have been better to go with a better BMS like the ones from Bestechpower.com and they are a lot cheaper than BMS battery and can handle the current.
since you are stuck with that BMS, you can get away from using the heavy switch by rewiring the BMS to B+ connection. the red wire from the battery should go directly to the controller. you can run a small wire from the battery to the B+ terminal on the BMS and put a switch in that wire. a small DIP switch like i use will turn off the BMS and that will turn off the battery so you can make connections to the controller without a spark.
you should not carry the full battery current to the BMS, just the circuit current to drive the BMS.
you don't show a picture of the controller, just the motor so i assume you mean controller.
that BMS will not handle the current the lipo packs can push imo. it would have been better to go with a better BMS like the ones from Bestechpower.com and they are a lot cheaper than BMS battery and can handle the current.
since you are stuck with that BMS, you can get away from using the heavy switch by rewiring the BMS to B+ connection. the red wire from the battery should go directly to the controller. you can run a small wire from the battery to the B+ terminal on the BMS and put a switch in that wire. a small DIP switch like i use will turn off the BMS and that will turn off the battery so you can make connections to the controller without a spark.
Attachments
jbalat
10 kW
dnmun
1 PW
right, and the controller goes in between the X's.
there should be no current to power the processor now. it gets power from the top of the top cell. through the big surface mount power resistor. somehow it gets to the processor from the P+ terminal. i think.
the fuse in the charger line is important in case the charger lead shorts out to the battery at a lower level or to ground. i have only seen one BMS that incorporates a fuse there. the one for that panasonic battery that pvdm had the problems with. that fuse had blown on his.
there should be no current to power the processor now. it gets power from the top of the top cell. through the big surface mount power resistor. somehow it gets to the processor from the P+ terminal. i think.
the fuse in the charger line is important in case the charger lead shorts out to the battery at a lower level or to ground. i have only seen one BMS that incorporates a fuse there. the one for that panasonic battery that pvdm had the problems with. that fuse had blown on his.
jbalat
10 kW
dnmun
1 PW
the BMS operates as a circuit breaker in the ground of the battery. the reason they put the P+ there is to bring the full battery voltage to the BMS so they can power the processor. i looked but did not see a trace from the top sense wire to the processor, you might be able to find one. so i think the power for the processor comes from the P+ terminal on the BMS. if you cut off that power then the BMS will shut off.
you bypass the BMS with the power cable on the positive side and run the power directly to the controller. the little wire for the BMS power only requires a tiny DIP switch like i use. mine was 50 ct for $7 so 14 cents each. it will turn the battery off so you don't have to spend big bucks on the contactors or precharge circuits.
you bypass the BMS with the power cable on the positive side and run the power directly to the controller. the little wire for the BMS power only requires a tiny DIP switch like i use. mine was 50 ct for $7 so 14 cents each. it will turn the battery off so you don't have to spend big bucks on the contactors or precharge circuits.
jbalat
10 kW
I also receive this response from another member.. So thanks for everyones help.. \
I will update my picture tonight so others can use it in the future for reference
•keep the sBMS always connected to the cells, no power off switch in the P+ supply line (you might kill it!). The BMS draws just a few uA in idle / sleep mode, so don't worry about depleting the battery.
•The sBMS interrupts the 'minus' lines, thus all negative (thick) power cables are connected to the sBMS: the one to the charger (C-), the one to the Battery (B-) and the one to the power supply (controller and other board supply) (P-)
•The positve end of the battery (B+) as well as the Charger (C+) as well as the controller (P+) need to be connected together too, but it is not necessary that this is done on the sBMS. The P+ pad is just that large so that it could be used as a connection terminal - however, you can connect them wherever it is convenient for you e.g. at the battery B+. Nevertheless you have to connect the BMS P+ terminal with the battery B+ for its own supply, but a thin cable is sufficient since the BMS draws over this connection only a few mA.
•But: you must connect/power up everything in the correct sequence otherwise you might be damaging the sBMS (1st B- to battery, 2nd P+ to battery, 3rd balancer cable; disconnect in reverse order. Therefore no BMS power-off switch!)
•the BMS acts as a fuse thus it is not really necessary to add one. I do keep a fuse in the plus line of the ebike board supply (light, controller supply, CA, ...) . I keep the fuse externally and use it as my key/kill switch . If I pull it the ebike is electrically dead...
I will update my picture tonight so others can use it in the future for reference
•keep the sBMS always connected to the cells, no power off switch in the P+ supply line (you might kill it!). The BMS draws just a few uA in idle / sleep mode, so don't worry about depleting the battery.
•The sBMS interrupts the 'minus' lines, thus all negative (thick) power cables are connected to the sBMS: the one to the charger (C-), the one to the Battery (B-) and the one to the power supply (controller and other board supply) (P-)
•The positve end of the battery (B+) as well as the Charger (C+) as well as the controller (P+) need to be connected together too, but it is not necessary that this is done on the sBMS. The P+ pad is just that large so that it could be used as a connection terminal - however, you can connect them wherever it is convenient for you e.g. at the battery B+. Nevertheless you have to connect the BMS P+ terminal with the battery B+ for its own supply, but a thin cable is sufficient since the BMS draws over this connection only a few mA.
•But: you must connect/power up everything in the correct sequence otherwise you might be damaging the sBMS (1st B- to battery, 2nd P+ to battery, 3rd balancer cable; disconnect in reverse order. Therefore no BMS power-off switch!)
•the BMS acts as a fuse thus it is not really necessary to add one. I do keep a fuse in the plus line of the ebike board supply (light, controller supply, CA, ...) . I keep the fuse externally and use it as my key/kill switch . If I pull it the ebike is electrically dead...
dnmun
1 PW
you do not have to connect the sense wires in some particular order. that is just silly. you just do not wanna plug them in backwards but you can plug the sense wires in any way you want. and the guy who sent you the secret message does not know what he is talking about if he said turning of the power to the processor will kill it. that is just stupid so that is why he told you that in secret. he figured you were gullible and saying it publicly would require he know what he was talking about.
the idea behind turning the battery off with the switch in the BMS power is so that the battery is not active when you plug in the controller so there is no spark to eat up the contacts. you do not need a fuse in the main power like i said since the BMS will provide short circuit protection but a fuse in the charging line is protection against shorts there.
the idea behind turning the battery off with the switch in the BMS power is so that the battery is not active when you plug in the controller so there is no spark to eat up the contacts. you do not need a fuse in the main power like i said since the BMS will provide short circuit protection but a fuse in the charging line is protection against shorts there.
jbalat
10 kW
I guess my concern is that only a few people have really had much experience with this particular board.
I am willing to take on board any comments and in the end I hope that the board works and will not be damaged by a wrong connection.
I understand that on any forum most of the information you get is just peoples opinions. Some are based on experience and others on perceptions. I'm sure no one wants to go out of their way to mislead you.
Like I said I appreciate everyones help
I am willing to take on board any comments and in the end I hope that the board works and will not be damaged by a wrong connection.
I understand that on any forum most of the information you get is just peoples opinions. Some are based on experience and others on perceptions. I'm sure no one wants to go out of their way to mislead you.
Like I said I appreciate everyones help
dnmun
1 PW
i understand that you are not familiar with the way it works. i have worked on identical BMSs using the O2 micro processor. that pcb took power from the top of the top cell but on this pcb i could not see where the trace was running from the top of #13 on your board. if this is your board. i told you then that you could look for the trace since the picture is not adequate to make out the traces on the board running to the processor.
it is infinite bad luck to have full battery voltage less the 1mm away from the P- terminal of the BMS because any contact between the two will instantly short out the entire battery and blow all the mosfets to smithereens. and that is not an opinion. it may be news to you. it is just sad to see that others send you secret messages to misinform you because they can see you are vulnerable to it. usually they misinform people on the threads.
it is infinite bad luck to have full battery voltage less the 1mm away from the P- terminal of the BMS because any contact between the two will instantly short out the entire battery and blow all the mosfets to smithereens. and that is not an opinion. it may be news to you. it is just sad to see that others send you secret messages to misinform you because they can see you are vulnerable to it. usually they misinform people on the threads.
jbalat
10 kW
Hey dnmun, thanks again.
Just thought you should know that I contacted the guy first after reading some other threads on the forum so not his fault... Dont want to start anything here.. Just after some help, thats all...
Just thought you should know that I contacted the guy first after reading some other threads on the forum so not his fault... Dont want to start anything here.. Just after some help, thats all...
jbalat
10 kW
Just wanted to let you know that the BMS worked with the supplied 400W charger. It cut off perfectly at 50.4v
Its a credit to the guys at BMSBattery. I'm glad the board was programmed correctly and everything works as it should.
Just a small change to the last design. Im not superstitious but...
1. I connected up the board with thin red wire switch in the off postion and no balance plug.
2. Switched power on to power up the bms
3. Connected the balance plug
4. Turned key to power up the controller and all is good
Note: for simplicity the diagram does not show the ebike controller.. Just assume it is where the hub is..
Its a credit to the guys at BMSBattery. I'm glad the board was programmed correctly and everything works as it should.
Just a small change to the last design. Im not superstitious but...
1. I connected up the board with thin red wire switch in the off postion and no balance plug.
2. Switched power on to power up the bms
3. Connected the balance plug
4. Turned key to power up the controller and all is good
Note: for simplicity the diagram does not show the ebike controller.. Just assume it is where the hub is..
Attachments
dnmun
1 PW
yep, that is very effective. if the wire to the B+ spot on the BMS shorts to the P- then the BMS should shut off but if it doesn't or the if the mosfets themselves are shorted by the current surge then having the smaller wire will help because it should burn open immediately. a large wire would not open right away and so more heat would be generated in the short. that is the fire risk. now minimized.
with the switch turned off the battery will not charge or discharge. since there is no current to the processor then it does not send a voltage to the gates of the mosfets so they are both turned off. this helps when you have to connect the controller since there is no spark so the connectors aren't damaged. but you can also now leave everything wired up and just turn off the battery when you don't use the bike and it will be essentially locked 'off'.
you got it all covered imo. i think those are the Renasis mosfets, high quality, should handle 30A but i don't think they can handle all your zippy can make but the BMS should shut down if the current gets to be too much. they may have an over current cutoff spec you can use. BOL
with the switch turned off the battery will not charge or discharge. since there is no current to the processor then it does not send a voltage to the gates of the mosfets so they are both turned off. this helps when you have to connect the controller since there is no spark so the connectors aren't damaged. but you can also now leave everything wired up and just turn off the battery when you don't use the bike and it will be essentially locked 'off'.
you got it all covered imo. i think those are the Renasis mosfets, high quality, should handle 30A but i don't think they can handle all your zippy can make but the BMS should shut down if the current gets to be too much. they may have an over current cutoff spec you can use. BOL
NeilP
1 GW
Just received a 16 s BMS from BMS Battery
Anyone know the wiring for the main wires.
Markings are, P, B & C
C will be charger? Or is it Controller
B to the Battery ?
Or does B go to controller as Battery out and P goes to the Pack?
Anyone know the wiring for the main wires.
Markings are, P, B & C
C will be charger? Or is it Controller
B to the Battery ?
Or does B go to controller as Battery out and P goes to the Pack?
all the solder spots connections are negative wiring (except if you see a B+, but is not quite the common)
so your positive main battery lead go directly to the connectors
B- = to the battery negative main lead
P = to the negative pole of the discharge connector (controller)
C = to the negative pole of the charging connector (charger)
so your positive main battery lead go directly to the connectors
B- = to the battery negative main lead
P = to the negative pole of the discharge connector (controller)
C = to the negative pole of the charging connector (charger)
NeilP
1 GW
Nice, thanks.
NeilP
1 GW
Doh. stupid of me to ask..That is what comes from posting from bed at 2 o'clock in the morning while half asleep.
Should have just gone to the webpage
Should have just gone to the webpage
Hi all, how does one switch off and on the BMS in order to avoid the nasty spark when plugging in the controller? I tried cutting one of the balance wires while the BMS was on to make it turn off, but it still delivered current no matter the missing reading on cell 11.
There was a thread about this BMS about 18 months ago. All I can remember is that it had O2 in the title, which is the type of microprocessor on it. The conclusion was (IIRC) that it was vital to have the P+ connected before the balance leads, so do not switch off that switch on P+. The guys also discovered programming errors.
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