This lill guy is hiding in the dark, so cant quite tell. But maybe I’m paranoid.
If you have a multimeter, please check, I’ve swapped it on all diebies so far, s’posed to be 15Ohm but usually fails and reads Mohm after awhile:
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Since we’re discussing defect DieBieMSs here.
I have one that shows weird behavior during (regenerative) braking. If I try to slow down to much, my brakes cut out. It is definitely the BMS because with my other DieBieMS everything is fine.
Also the display did this when the brakes stopped working.
(I’m not sure if that is related tho. I found a lose data cable on the display)
Anyone with a DieBieMS experienced something like this before?
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Those screens are very cheap and sensitive. Think I have one left that is alive.
You should try monitor the fault Diebiems for a error msg. Easiest way to find out whats wrong
Switch it down to 200 Ohm on the dmm for better accuracy 
looks like its starting to give out tho
It happens to me sometimes with a full battery (12s) My brakes still work untill I come to standstill. The voltage from the motors keep the vesc and receiver alive. Then it shuts down and I have to reboot. Prolly a voltage spike…
Any update?
I’m presuming the one I sent back never made it through the post system so will be in for a new one
On 200ohm it says overload… So this is the best I can t at the moment. Do you thinh this could be an issue?
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Then the 700 reading is prob accurate. I would swap that resistor asap. Bound to do strange things/make it go dark completely. Entire supply for the MCU goes thru that resistor
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Sign me up for 2 BMSes, Sam.
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Me too please. Tell me who to pay
Sam - just looking at time here - and manurfacturing. is 2020 realistic?
If we aren’t able to get the v0.10 changes, I’d vote for another batch of the same v0.9 from batch 3. I have three of those and they are all installed and working but need more.
Still no news on the v0.10. @JTAG.
There are repair cases related to the the changes I believe.
That’s why I am reluctant to move forward. Also not feeling too comfortable with not able to get any feedback with Danny.
So this is on hold for now.
Sam
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Danny is alive though?
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Wait he lives in the netherlands…
Danny just doesnt care, even if you ping him.
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Tell me about it…
If you send him an email at danny@diebie.nl you might get an answer. I did after 3days hah
Dear all,
My apologies for the lack of response and sometimes late response, the whole BMS hobby expanded, there are now many variants of the DieBieMS ( named differently ) in the market with a great spread in functionality from working with a fast electrical switch, to systems with integration on large PCB based busbars to working with bluetooth and or 4G for telemetry updates. These systems are integrated in low cost powertools available in supermarkets worldwide, ranging to rovers for rescue robots all the way to e-foils. The total ( all batteries combined ) amount of capacity monitored now is worth about 70MWh (megawatt hours, insane! Luckily no safety events happened that I am aware off )… Some systems with the very first version of the DieBieMS run for 4 years now, that is the same version as the one that is open sourced.
A shit ton of stuff got learned from those systems, some of which might be interesting to integrate in an Esk8 or in light weight electric vehicles. The desires / requirements of what is needed for an Esk8/LEV BMS also shifted, almost all ‘modern’ ESC’s now have a build in anti spark switch with push to start. And who wants to carry a unique charger for every device they own?!?!?, everything is going to be USB-C PD in a year, so that needs to change.
Then there is the current design ( topology driven, the measurement chip is directly connected to the main large current carrying wires ) that knows situations where it can damage the BMS, most often the cell measurement chip and/or the cell sensing network get damaged when the pack is damaged or improperly connected. After a few repair of boards send in + experience of people around me the following items cause front end damage:
- A lose balance wire that touches the pack in on a different voltage level then the intended one. The inputs of the cell measure chip are only rated up to 6V from the input one step lower, when this voltage is exceeded the input network will fail or the chip input will fail. Lose wires can occur when they are improperly attached, but also during assembly when they touch something accidentally. There touched will almost certainly result in a fail. So be careful when mounting balancing wires!
- When a battery pack is fully operational and somewhere in the pack in the main current conductor breaks somewhere ( a P-group to P-group series connection ) then the full pack voltage appears across the balance leeds input. These significantly high voltages are very damaging to the cell voltage sensing elements. So make your connections thorough and inspect them regularly ( often stiff nickel connections can break and then you have a split somewhere in the pack.
- Incorrect wiring of the balance connector. The balance connector has many connections, and when you swap two or more you will exceed the capabilities of the allowed input voltage and you will break the BMS.
- Incomplete connections; when you connect everything ( all balance wires ) but forget the main negative/positive wire (or they are improperly connected) the output current will flow trough the balance wires and measurement network, these wires+components are of course not meant for those currents so they riskt to break. Connecting the USB, which turn the BMS on, with improper main wiring turn the BMS on and therefore also the output, this should be prefented.
Weirdly enough the last item ( 4 ) occurs the most and is the easiest to fix by going to an isolated cell sensing topology. Over the upcoming winter months I will be designing a cheap and small formfactor charge only BMS that will also act as a BLE receiver for maybe an app. The small charge only BMS will be opensource as well, I am not sure yet.
Therefore I would advice everyone to wait for that one. Very likely with short follow-up I will add a charge / discharge BMS to that ass well to serve the people who like to have a BMS that fully protect the battery.
I will start a new threat that everybody can follow, will post the link here when I do.
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