5-16S Smart Tiny BMS preorder - 30/150/750A rated

[BMS1]

I'm wondering the same. @circuit, could you explain a bit more about the ignition feature? I would expect that once activated via the windows software, the BMS would shut down the load outputs if the selected ignition input is held low, and it would reactivate the load, once the ignition input is pulled up. Is that correct?

Do I simply tie the input to Bat+ or should I use a resistor divider? It seems all inputs are 70V tolerant.

If the ignition input is held low, will the +5V output on the USART connector shut down as well? I'm planning to use this output to add an info screen, but I would not want that MODBUS requests would keep the BMS awake despite the state of the ignition input.

[circuit]

I'm wondering the same. @circuit, could you explain a bit more about the ignition feature? I would expect that once activated via the windows software, the BMS would shut down the load outputs if the selected ignition input is held low, and it would reactivate the load, once the ignition input is pulled up. Is that correct?

Do I simply tie the input to Bat+ or should I use a resistor divider? It seems all inputs are 70V tolerant.

If the ignition input is held low, will the +5V output on the USART connector shut down as well? I'm planning to use this output to add an info screen, but I would not want that MODBUS requests would keep the BMS awake despite the state of the ignition input.

You are right on everything. When ignition function enabled, it will control load switch. All inputs will take voltage up to B+, but it is is recommended to add a small fuse or current limiting resistor to protect in case of misconfiguration, since these can also be outputs.
5V is switched off during "off" state to offer excellent quiescent current (70μA).

[BMS1]

Awesome! Thanks so much for your quick reply. I just placed the order.

[Freemann]

Does anybody known if its possible to use one the 3 motor hall sensor as input for the BMS?

So one hall-sensor will be connected to both the Controller as the BMS.

[circuit]

Does anybody known if its possible to use one the 3 motor hall sensor as input for the BMS?

So one hall-sensor will be connected to both the Controller as the BMS.

Yes, it is possible. Just add a diode from hall (Anode) to BMS digital input (Cathode). 1k in series is also recommended.

[Freemann]

Does anybody known if its possible to use one the 3 motor hall sensor as input for the BMS?

So one hall-sensor will be connected to both the Controller as the BMS.

Yes, it is possible. Just add a diode from hall (Anode) to BMS digital input (Cathode). 1k in series is also recommended.

Great!

Would this OK?;

Code: Select all

Hub Motor -> Hall Sensor A -> 1k resistor -> (A) diode 1N4001 (C) -> DI_DO1 of TinyBMS

[circuit]

Would this OK?;

Code: Select all

Hub Motor -> Hall Sensor A -> 1k resistor -> (A) diode 1N4001 (C) -> DI_DO1 of TinyBMS

Seems fine.

[vex_zg]

Does anybody known if its possible to use one the 3 motor hall sensor as input for the BMS?

So one hall-sensor will be connected to both the Controller as the BMS.

What would be the purpose?

[circuit]

BMS will calculate speed, and Android app will display it.

[kosf]

Hi All,

Does anyone know if there is a USB cable available in the US that will work with this BMS?

To get it from energus, just the shipping is $50 so im trying to avoid that.

[kosf]

Does anyone know if there is a USB cable available in the US that will work with this BMS?

Sorry if all this is a bit off topic, but it should be quick.
I would buy it from Energus if I could get it quick enough and if the shippers didn't charge us $50. Which is here:
https://energusps.com/shop/product/usb-uart-cable-34

Of course I will have to make a connector if I buy it from somewhere else.

After asking around I realized UART is fairly common. Still not sure which will really work...

would this work?
https://smile.amazon.com/WINGONEER-CP21 ... B01LRVQIFQ

or this
https://smile.amazon.com/HiLetgo-CP2102 ... B00LODGRV8

Both those use the CP2102 chip, like the one from energus.
Any ideas ES?

[Altair]

Hi Circuit,

I sent you an email two days ago from your web site's contact page, regarding my problem with the app ebike analyzer that won't stay open.
I am waiting for your reply so that I can place my order for a TinyBMS and accessories.
Are you still selling them?

[circuit]

Hi Circuit,

I sent you an email two days ago from your web site's contact page, regarding my problem with the app ebike analyzer that won't stay open.
I am waiting for your reply so that I can place my order for a TinyBMS and accessories.
Are you still selling them?

Hi Altair,
Your email was likely forwarded to our support team, and in more complex cases information is usually bypassed to engineers for a comment. So this can take time.

In your case, ebike analyzer (the Android app) is a third party product and your best chance would be to contact the creator directly. I believe his contacts are available on google play store.
Let me know when you sort it out what the problem was, as this is the first time I hear about this.

[Altair]

All right,
Thank you very much for the quick reply!

[AkifH]

Hi there,

We are trying Tiny BMS 150A for some time. But we are having really tough times. It seems like there are problems with its stability. We have two critical problems:

1. For our 24V battery pack, after several days of flawless working, now when we switch the output with ignition pin, output voltage starts to decrease gradually until 15-16V and fluctuates between ~20V and ~15V. If we disable ignition, output is constant and OK however we need ignition so this stops us from using the BMS. We ordered a new one and the result is the same.

2. Another problem is about charging. We switched to two channel charging/discharging. TinyBMS is set to detect charger "internally" (I wonder the mechanism behind this word). Again after working several times with no problem, now the charger is not detected and charging does not start for about %80 percent of our trials (it shows a random behaviour). FYI, our charger is Meanwell PB-600 (24V, 21A maximum charging current). It switches on the output after detecting the battery voltage. So we can not use other charger detection methods like digital inputs etc. Still we tried charger detection with digital input, by applying an input manually, in this case it start charging. We also tried our charger with a lead acid battery, it charges the battery with no problem. So we think we have problem with TinyBMS charger detection.

Note: There is no failure event in Battery Insider app with any of our problems. Our firmware version is 242. We also tried older firmware version (238 and 241 etc.). We tried resetting it several times with no luck. Since it was working fine before, we are suspecting a hardware failure.

[Freemann]

Which firmware are you using?

I also see strange behaviour with charging.
Balancing is not always doing its thing and the battery is not always charging to an 100%.

Already had contact with Energus technical staff, send them some screenshots and a video.
The say everything is looking normal and there are no problems. Still charging is cutoff and SOC is in most cases not 100% after charging.

Here's the video;
https://youtu.be/kobrakbN-s8

The video shows that after a BMS restart, its not starting to charge.

[circuit]

It may abort charging in case charger voltage is slightly too high and cells go over their preset voltage. To fix, decrease your charger's voltage slightly to meet exact voltage per cell.
Note that BMS can't change voltage of charger or battery output, it only switches either on or off. So if your charger is set incorrectly, it will stop charging earlier due to overcharge or current dropping before full charge is reached.

Since BMS does not set output voltage and only switches it on/off, any values that you see with multimeter on output with no load is just a residual floating charge and does not mean anything. If it does not switch on with ignition input, it means there are some other issues...

Charger detection may fail if initial charging current is very low. Some fancy china chargers try to detect a battery before switching on and sometimes this fails.

If you are having problems, please drop an email to support at energusps.com, try to include as much information as possible in the initial email, as sometimes it is very hard to diagnose remotely, going through tens of emails.

[AkifH]

Since BMS does not set output voltage and only switches it on/off, any values that you see with multimeter on output with no load is just a residual floating charge and does not mean anything. If it does not switch on with ignition input, it means there are some other issues...

Possibly. But when ignition is not connected, it floats wildly (you even cannot read any value with a multimeter), when I connect it to 24V, it starts from a value like 23V and decreases continuously with some fluctuation. Even a brand new TinyBMS resulted in the same behaviour, so I think this is an implication of a hardware issue.

Charger detection may fail if initial charging current is very low. Some fancy china chargers try to detect a battery before switching on and sometimes this fails.

In fact MeanWell is not a fancy china charger. It is possibly one of the most reliable chargers in the market (and Taiwan made ). I do not think this is an issue with the charger, it detects the battery and tries to start charging however since TinyBMS does not switch charging FET on, it can not provide enough current and gives up. As I mentioned there are no failure events, or "charger connected" events at Battery Insider event screen. Maybe the charger detection current threshold is a bit high in the BMS firmware, I do not know.

If you are having problems, please drop an email to support at energusps.com, try to include as much information as possible in the initial email, as sometimes it is very hard to diagnose remotely, going through tens of emails.

Hope to solve the issue with support team. I will post back the result here.

Thanks.

[Samil]

Hello,

I have been using Tiny BMSs (150A V2.1) for some time. It is used in a considerably large battery pack (24V 100Ah). For battery charging I could go up to 0.5C(considering battery health) which is 50A cont. But when I check the charging limit of the BMS it is stated as 30A max. cont.

On the website there is an explanation as " Discharge/Charge/Regen current: 750 A* - with external relays and current sensor"

Here the questions are;
- Could using external current sensor only solve the issue? (When I checked the schematic image of the BMS the "Detect" block has no connection/relation with external sensor)
- What is the effect of using external relay for charging? (In schematic images, CHG-connection - going through detect block and mosfets and CHR+ is directly connected to battery cells for both 150A and 750A - no connection with external relay)

Note: Maybe explanation of how detect works would be beneficiary for me to understand the dynamic and comment on the issue with possible solutions on my side.

[circuit]

Regarding current handling, there are 3 options:
1. "30A" model with integrated shunt for currents up to 30A.
2. "150A" model with integrated hall sensor for currents up to 150A.
3. "150A" model with external current sensor. Once this sensor is connected, BMS will detect it and allow higher current values to be entered.

Some time ago there was a firmware update to improve this behavior a little, so make sure you are running the latest firmware. Contact support for latest file.

Charger detection can be done in several ways, if contactor is used. First you need to configure a pin for charger relay control. Then there are two options:
1. Charger can be detected with internal circuitry (select if in settings). Connect charger directly to usual CHG for detection, and also to a relay, which will be controlled from one of programmable pins, that you set.
2. Charger can be detected by one of programmable inputs. This is useful for use with chargers that have "power good" or similar output - it provides this signal to a BMS and then it activates the relay (if all other parameters are in acceptable range).

[Samil]

Thanks for the answers.

But, my question was specifically for charging current. Although my BMS is 150A verison the "Charging Current" is limited to 30A on Battery Insider program although you defined the current handling as a single term in your answer as I understood (not seperated values for charging and discharging).

Regarding current handling, there are 3 options:
1. "30A" model with integrated shunt for currents up to 30A.
2. "150A" model with integrated hall sensor for currents up to 150A.
3. "150A" model with external current sensor. Once this sensor is connected, BMS will detect it and allow higher current values to be entered.

And when I checked the product website it is also stated as "Charge current sustained: 30 A** "

So actually all my intention with those 2 questions are how could I increase that "30A value for 150A BMS" and hope to understand how it works.

[circuit]

Yes, charging current is lower, as it is handled by single mosfet. To gain higher current, you will need external switch (relay or solid state relay). Internal current sensor can still be used for currents up to 150A.

I have just discussed this non-start issue with our engineer and he confirmed there are some compatibility problems with some "smart" chargers, which mentioned MeanWell is. It works fine with usual CCCV power supplies, but smarter devices sometimes struggle, as we get two smart devices toggling each other and missing the window to turn on.
We will be acquiring several "smart" chargers to analyze their behavior and to adapt our firmware.
If someone could lend us a charger for couple weeks, it would be great, as we would be able to adapt the firmware for your particular model.

[Samil]

Hi,

Ok, your limit for charging is due to single mosfet, that is clear. The point is, how could the internal sensor is used for current sensing while switching the line outside with external relay ? (Current is not flowing through board, similar to 750A load switching)
In that case there has to be an external current sensor even the internal one could measure up to 150A, as I guess?

About smart chargers, my guess also same with you as there is somehow a conflict occurs while detecting current/voltage. A firmware upgrade would be great if you get a MeanWell charger quickly.

Thanks.

[AkifH]

I have just discussed this non-start issue with our engineer and he confirmed there are some compatibility problems with some "smart" chargers, which mentioned MeanWell is. It works fine with usual CCCV power supplies, but smarter devices sometimes struggle, as we get two smart devices toggling each other and missing the window to turn on.
We will be acquiring several "smart" chargers to analyze their behavior and to adapt our firmware.
If someone could lend us a charger for couple weeks, it would be great, as we would be able to adapt the firmware for your particular model.

Hi circuit,

Since we are in a bit urgent state, can there be a quick modification to the firmware? Maybe this can be an option: with a selection from Battery Insider, charge FET can be always kept on and BMS can switch to Charging state if current flows from charger to the battery (current sensor can detect this).

Those who are using "smart" chargers like us can configure this option to keep charge FET on, not rely on internal charger detection mechanism.

I know that we can trigger charger detect externally with an input pin but if we use this option to keep charge FET always on, BMS always shows its state as "Charging" even if no current flows through it.

[DaDo.Bzz]

Hello Circuit.

Just find your BMS. Looks great! Will order it.

Wanna ask about BT. It Is BTLE protocol? What baud speed it is? When I was doing some test over BTLE and Arduino I ess able to reach something like 2000 chars per second. How many updates per second third party app request from bms?

Anyway, dont you thinking about 100A continous current BMS on board?