Load must equal battery???
I hat that confused. I will switch the red and black wire
Here is a step by step video of how to calibrate the Amp Draw on a BMS 24 and it’s Shunt.
Starting this project I really wasn’t that great with electrical or reading wiring diagrams, but after working with this and up all night last night looking at wiring diagrams, I believe my Charger - wire is in the wrong location. Currently if you look at the photo the charger - is hooked to the battery. all the wiring diagrams I have seen the charger - is ahead of the Shunt creating the load back thru the shunt so the WH will show up upon charge. Am I correct? I have attached my current wiring diagram. I hope you can make sense of this. As @grantwest and @Inwo would say don’t make sparks, so am I on the correct path?
Grant I watched your video and if I am correct your charger is in front and the neg of that charger is before the Shunt and the shunt would then attach to the batteries?
Trying to get this right before I throw sparks and my day is ruined.
Current Setup
Am I correct, Should I take the Neg from the Chargery cord and attach it on the controller side of the Shunt? (directly on the shunt end along with the Neg that heads to the Controller)
You are correct the Charge current should go THREW the Shunt this way when you charge you will see Amps rise and KWh Rise as you charge.
If you have the charge wire on the battery like I had it the it works fine your BMS will just not see the Energy going threw the shunt and into the battery.
My Chargers output wire is on the Shunt so your correct. Go ahead and switch it Just the charge wire. If your nervous turn the BMS off and disconnect the JST plugs. But if you can just take off the charge wire with out removing the battery connector cable then your good to go. You now know what removing the battery connector cable dose so don’t do that 
Thanks guys, I am learning.
Now if I have learned correctly, before I make that move, I want to run my Battery down to 3.5 so when I charge the WH will go up so I know how much WH I have left till empty? Correct?
I don’t bother running it down. And I don’t reset the KWh numbers, each time I charge. Simply charge and drive charge and drive
I guess it’s by habit that I Re charge after every use. That way if I decide to go across town, I always have a fully charged car
What I was thinking and I could be wrong. By running it down to the correct Empty and Charging the WH would Rise to the Full amount. So if I did drive 5 miles and then charge the WH would go back to that Full amount? just was sitting here thinking.
I think it you got the battery to 3.5 v Empty.
Then Reset the BMS so the KWh reads 0
Then charge up to let’s say 3000 the KWh would drop down to zero when you hit 3.5 again.
This is just not the way to worry about it.
Just charge up and drive it. The BMS most important job is just to Balance and give you a Idea if your cell Voltage so you can decide when to get rechargerd or how much further you can go
@Inwo and @grantwest I moved the charger neg to other side of shunt shown in pic below and when I charge still 0.0wh and now -515.8a is show. I stoped the charger unplugged and changed the red and black wires and the display shows the exact same. Any thoughts. It really doesn’t bother me since I only really look at the 3.?? Volts to see how much is in the battery till empty
Correct amp reading is necessary for proper bms function.
Shunt input may be damaged or you may have pushed buttons and need to recalibrate shunt.
Grant has a video on that.
Here is a video of how you calibrate the current draw on a BMS 24
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Thanks guys I will try to recalibrate it, I hope that is all it is…
Well I was finally able to get out and do a long run 15.7 miles on this Chevy Bolt Battery. I was really impressed, I started out with around 3.97v as the max and ended the run with 3.68v still left. I still have not charged the battery as I hope to keep going this weekend to see how far I can get on this charge. I have a app that I use for skiing that I thought would be interesting to show max speed and the hills I climbed during the run. The cart was fast however the shocks are VERY stiff, I really need to look into getting softer shocks if I am going to make this my fun commuter around town.
This lower chart is hard to read, I went to my kids soccer practice and hung out for a hour and half, then went to get ice cream and then meet up with neighbors. so those straight lines are me pausing the app and restarting as I was starting to move.
what was left after the 15.7 mile trip
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Tyson Very Cool. How many kids did you have in your cart? I see you had some elevation changes 1000 feet or so of climbing.
It’s great to see REAL world data. All these people that claim 20+ miles of Flooded Lead acid range. I would love to see them Data Log their miles like you have great job
Well, I think it was more like 375 feet of total climbing. the 1000 feet is max altitude I went down to around 775 altitude. I had two kids in the cart one was 50 pounds and the other was 75 pounds. I would really like to run the cart down to around 3.5 to see what the total range is so I know how far I can really push it so I am not out and about and needing a charge
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