Chargery 16T decalibrated?

kuranaga

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Hi

my new chargery 16T seems decalibrated. Cell voltage measured with multimeter at bat terminals AND at the chargery cable port are all 3.290-3.291 but the BMS shows 3.26 - 3.33... WTF

seems these BMS come completely decalibrated from factory?
 

kuranaga

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My first question is:

What meter are you using and is THAT calibrated?
SURE! UNI-T UT203

Ive also checked with a voltcraft 4095, which is less exact (less decimals) but still shows me same thing (3.29-3.29).

Even a decalibrated meter would be constantly off, but not 3.26 on one cell and 3.32 on another.

Now that BMS16T gone totally crazy. Showing me low voltage of 2.4V on the cells (while they still have 3.29!).

the "BMS" is crap.
 

kuranaga

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even total pack voltage is wrong! all cells are brand new and 3.29(1)
 

RV10flyer

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If you’ve verified with two meters, then I believe you. I use about 15 different calibrated and uncalibrated meters daily. I’ve never seen that much variation (0.313V). Ensure ALL connections are good. Contact the manufacturer. They will take care of you.
 

kuranaga

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can I trust this product if it went bad so quickly? Just 10 minutes of bat connection and it messed up. What about running it 5 years in harsh conditions?!
 

kuranaga

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ps if I connect it to ext power supply (instead using bat power) then it is back to the initial state, showing the cells 3.26-3.32 (which is still off!). Seems the internal circuit is gone bad. power regulation / stabilization / ADC power supply, probably.
 

DLTooley

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Bad from the get go and bad over time are usually different things with electronics, but not necessarily.
 

kuranaga

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ps I firmware updated it before ever running, but the firmware is correct and latest version (for 16T-300A!). doubt it could have messed something, it seems some ADC issue to me.

it is showing random values on every reconnect. sometimes just lo voltage, then 3.16 or so, or 3.24V on some cells. totally unpredictable
 

Short_Shot

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If you’ve verified with two meters, then I believe you. I use about 15 different calibrated and uncalibrated meters daily. I’ve never seen that much variation (0.313V). Ensure ALL connections are good. Contact the manufacturer. They will take care of you.
Agree.
 

JoeHam

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can I trust this product if it went bad so quickly? Just 10 minutes of bat connection and it messed up. What about running it 5 years in harsh conditions?!

My first suspect would be the BMS lead wires.

Clean ALL connections and double check your crimps or solder connections to the ring terminals.

Can I assume you are taking measurements directly at the terminals with your trusted meter and not through the BMS wires?
 

Steve_S

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What is the BMS Power, Harness or external, or from Battery Terminals ?
IF External, are you using the External Adapter with filters ?
Sense Lead Conections are very often teh cause of weird readings. Dirty Loose connections are the most obvious, but Burrs & Ridges on bussbars and other things are well known to contribute to such issues.

The BMS that is using the Factory Supplied shunt will be calibrated to that shunt. (Note Red (+) Wire is connected to the screw on the BATT Side of the shunt).
 

kuranaga

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My first suspect would be the BMS lead wires.

Clean ALL connections and double check your crimps or solder connections to the ring terminals.

Can I assume you are taking measurements directly at the terminals with your trusted meter and not through the BMS wires?
you do not understand eh? I said I measured AT THE BMS CONNECTOR and the voltages are the same, how could this be a bad crimp? maybe think first before posting eh?
 

kuranaga

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What is the BMS Power, Harness or external, or from Battery Terminals ?
IF External, are you using the External Adapter with filters ?
Sense Lead Conections are very often teh cause of weird readings. Dirty Loose connections are the most obvious, but Burrs & Ridges on bussbars and other things are well known to contribute to such issues.

The BMS that is using the Factory Supplied shunt will be calibrated to that shunt. (Note Red (+) Wire is connected to the screw on the BATT Side of the shunt).
again same thing: READ before posting!
 

kuranaga

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That TUDE will get you nowhere, enjoy the karma.
sure, still, read the thread before posting! if I say I measure at the BMS flat connector and the voltage is 3.29 then do not suggest it is a bad crimp. you cant be more off with your diagnosis.
 

Bob B

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It seems from previous thread that for some reason, the 16T is more likely to have voltage inaccuracies.
I would email Jason and see what he recommends.
 

JoeHam

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you do not understand eh? I said I measured AT THE BMS CONNECTOR and the voltages are the same, how could this be a bad crimp? maybe think first before posting eh?

Yikes !

So sorry to have not read your stuff carefully enough and to have wasted many seconds of your time. 😎

I’ll show myself out. Good luck with your issues.
 
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