It has value but sounds like not your setup.
I have a disconnect to the vesc. If I can get the e-switch to work, then I eliminate the need for the anti-spark which takes up more room and is one more potential failure point.
I have a batterysupports 10s bms with e-switch functionality integrated. Since i am still waiting for parts to arrive i have not really tested it but i can tell that with the e-switch switched off i still get around 9v on the output. That’s why i don’t trust it and will use an external e-switch. If you want i can upload some pictures.
Don’t external mosfet switches need constant power as well?
9V is massive! Mine is outputting about 2,5V. With 9V I would be afraid to power up my Vescs…
I have not connected it to a vesc yet. Maybe the voltage will drop once connected to the vesc, but eiterway i don’t trust it.
yah…maybe put a bit of load on it and see if it drops down a bit
i’ll just keep doing this. One switch to cut the power when i want, and one behind that to cut it in an overload or undervoltage situation. If the vedder switch fails into the on position like they do sometimes on rare occasion, then the BMS will cut power when the voltage runs too low from draining too much.
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Thank you! Could you take one more pic close up so i can read the numbers?
I asked Lilian at Supower how to add a switch. She said this is all that has to be done. I have not tried it yet.
I think the picture, the wiring she provided is telling the BMS that there is something wrong with the 10th pack so the BMS shutoff charging/discharging.
In the wiring example that @Stefan provided, I believe that is where they would put a thermistor, telling the BMS that the pack is too hot.
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Which numbers do you mean?
In your picture the switch is connected at a different spot than mine. I bought mine through ebay and left a message to enable the e-switch functionality and they mounted the switch leads at a different spot…
Did you try to zoom in the picture? I can read them very well (the two resistors you marked in your picture). They are 102 and 205.
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Thank you! I had originally looked on my mobile and it wasn’t working. Tried on my computer and can read them clearly.
I was thinking about this and could you set the vesc minimum input voltage to 10v instead of 8v? Then the VESC would be off and it wouldn’t matter if it was putting out 9v. Also, I was reading on some of the ebike forums that even though some BMS put out a voltage when off, they don’t put out any current and when a load is connected, it drops to 0v.
I just tested this and it´s right. With only the BMS attached I get 3,4V when off. I hooked up the rest of the system, so assembled everything and messured again and it´s only 0,11V now.
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electricity is so weird.
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It´s like water, you have to flow with it
-Bruce Lee 
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or in this case, its more like my oldest son. Sitting there on the couch with a lot of potential but as soon as i put a work load on him the potential collapses.
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