ElectricMotorcycleForum.com
Makes And Models => Zero Motorcycles Forum | 2012 and older => Topic started by: Doctorbass on April 27, 2012, 11:52:35 AM
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I got my zero 2011 motorcycle recently and decided to add a cell balance connector to allow me to monitor the cells voltage with the celllog8 cheap RC devices and also to actively rebalance it faster just in case. The interior wires i added to teh cells connections are 12 gauge with silicon skin and are good for up to 30A current.
That job took me around 7 hours of work and a bit of patience due to the cells bank that are in 2s configurations ( a bank is made of 2 group of 24 parallel cells in serie for 8.4V per bank ) and the connections of middle of both parallel cells group is not really accessible so i had to remove the nylon plastic that cover the copper braid that connect all them together and that is also conected to the BMS. But i connected so that i can cary high current for fast rebalance without potentially affecting the voltage reading of the BMS thru wire resistance loss.
The BMS seem to work with the charger trigger ( the white output wire) to balance the cells and stop pushing current when the voltage of one or more cells go to 4.200V. Than once it stop, the BMS continu bleeding the higher cells until the voltage of the high cell(s) drop to a given treshold near 4.170V.. than the charger enable again... and repeat this step until the voltage of the cells are with in 10mV diff from the low and the high cell, than the cahrger stop charging process and the green LED is on.
Doc
Here is few pictures for you guys: ;)
(http://www.endless-sphere.com/forums/download/file.php?id=81706)
(http://www.endless-sphere.com/forums/download/file.php?id=81707)
(http://www.endless-sphere.com/forums/download/file.php?id=81708)
(http://www.endless-sphere.com/forums/download/file.php?id=81709)
(http://www.endless-sphere.com/forums/download/file.php?id=81711)
(http://www.endless-sphere.com/forums/download/file.php?id=81712)
(http://www.endless-sphere.com/forums/download/file.php?id=81715)
(http://www.endless-sphere.com/forums/download/file.php?id=81716)
Also few images of teh interior of the delta Q charger
(http://www.endless-sphere.com/forums/download/file.php?id=81713)
(http://www.endless-sphere.com/forums/download/file.php?id=81714)
Doc
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Cool pictures!
Apparently the route to IP66 protection is to be liberal with the epoxy..
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Your workbench looks like mine, lol :)
Your wire may be good to 30A (I think the NEC says 20A for 12AWG, but that's for general wiring and generally longer lengths), but I doubt that little Molex plug is. How much current do you anticipate using for your "fast balance"?
In any case, thanks for the explanation on how "balancing" works. It supports the notion that leaving the bike plugged in as much as possible when not riding helps keep the cells balanced, as I presume no balancing is done while the charger is unplugged. I also presume this makes for healthier batteries.
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Your wire may be good to 30A (I think the NEC says 20A for 12AWG, but that's for general wiring and generally longer lengths), but I doubt that little Molex plug is. How much current do you anticipate using for your "fast balance"?
That's not a Molex, it's an Anderson Power Pole Connector. Hard to tell exactly which size he is using, but they look like they could be the PP30 (30A) connector.
http://www.andersonpower.com/products/standard-powerpole.html (http://www.andersonpower.com/products/standard-powerpole.html)
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Yes, It's the PP30 anderson connector.
Usually with the proper wire size or some modifications and being abole to get the 10 gauge wire to fit with them, you can get 35-40A continuous without any overheat since the heat is drained thru the wire and get the heat out.
In my lab i'm using alot of custom jigs and balance tool and adaptyers and cahrger and balancers and i all converted them to use these great PP30 connectors.
I am expecting to be able to balance at 30A... so every missing 1Ah of capacity in a bank will take 2 minutes to equalize.
As well, i know that the voltage on the cell and the voltage on the balance connector are different due to the resistance loss in the connector and wire lengh so to monitor the actual real voltage of each bank while i active balance them is to temporary disconect the balance curent and read the voltage once it is stabilized.
Using a kelvin voltage sensing connection method ( 4 wire method) would just be impossible to the complexity it require and the tons of connections to make.
I might also install some of my Meanwell 1000W and 1500W 48V power supply as charger for the zero. they are more powerfull and are 2-3 time more compact !
These are the RSP-1000 -48 and the RSP-1500-48. I might need to connect the inhibit to the white wire to let the balancer of the battery to control the charging process and also avoid overcharging. With some little mod i can acheive the 58.8V that these zero battery require with the meanwell psu by modifying the resistor divider that set the max output. I might also need to modify the OVP to abvoid it to kink in due to the higher tyhan normal voltage.
Doc
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wow! you guys are real techies! definitely out of my league... I'll stick to riding (even if it's supposed to go down to minus 3C tonight here... brrr...