Battery Temp Sensors Normally open?

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Nov 10, 2014
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I replaced my BMS with one that lacks a off on switch connection.

Could I use the temp sensor as one and keep it as a temp sensor?

Are temp sensors normally open, normally closed or are both used?
The BMS has a heat shield that blocks access to the temp wires, and I can of course
cut into the wiring, but before I started that I am trying to see if it is a bad idea or not.

Thanks
 
Still looking for this.

I can't locate a specific or generic wiring diagram.
Vruzen may be having problems due to the Gaza rocket shelling.
 
onemorejoltwarden said:
Still looking for this.

I can't locate a specific or generic wiring diagram.
Vruzen may be having problems due to the Gaza rocket shelling.

Temp sensor in our BMS are typically NTC thermistors . They have a resistance value directly proportional to the temperature of the environment. This changes, as temp changes.

NTC thermistors are resistors with a negative temperature coefficient, which means that the resistance decreases with increasing temperature. They are primarily used as resistive temperature sensors and current-limiting devices. ... NTC sensors are typically used in a range from −55°C to 200°C.

There are also PTC thermistors.

NTC thermisters are typically used in alot of places ( cars, EFI, our motors, BMS) , in leu of the more complicate thermos couple ( wire dissimilar sensing metal) .
 
thanks
I just sat through
https://www.coursera.org/lecture/battery-management-systems/1-3-4-how-to-sense-module-temperature-in-a-bms-37LiD
and between that and your helpful answer, I now have better grounding ( sorry).

I am assuming that the choice of whether the thermisters used in BMS are of the type that increases or decreases resisistance based on temp are a design call, rather than a standard, and my assumption that it was a binary switch was incorrect, though the logic of the board may use them in such a way. BMS supplier has been slow to respond, and I don't have a wiring diagram or easy board access.

I had been hoping I could use the low current case mounted switch, using the temp sensor circuit,
rather than a higher current inline switch on a power line , inelegantly mounted.
The Bafang BBHSD has a throttle that is hard to get off line, and is a safety issue, that the extra cut off/on-off helps address.

Thanks again
 
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