QS 205 50H V3 3KW Temp without sensor

[lukef]

Howdy, hope things are well. I neglected to specify a temp sensor when ordered the motor above. So I think it is safe if I never operate the motor above 3kw. So it seems at 72V and around 48Amps I could run "all day" with not much issue. However I understand that this motor is quite capable of a bit more power. I am using the motor as a winch and I found it seemed to go well pulling a load with power at about 5KW. But I want to somehow monitor temp and observe how far I can push my luck (likely aim to 6KW). I thought of just using an IR gun/camera and observe the motor. So I figure the side covers wont heat much but would I be correct in focusing my observations on the axel, is that where the motor will most likely sink the heat out through from the stator ?
Alternatively I am using a VESC 100 250, I wonder if there are any electrical attributes I can observe when driving the motor that might indicate I am pushing my luck.

Thanks
Luke

 

[hias9]

Are you really sure your QS205 does not have a temperature sensor?
Are there no small white cables at the hall sensor connector?
If not, adding a thermistor is a small and cheap job (thermistor costs about 1usd) which I would definitely recommend.

As far as I know most heat transfer is through the air gap, which can be significantly increased with ferrofluid or transformer oil.
Especially high phase amps at low rpm will heat up the motor and because heat transfer to the shell is quite bad, your stator winding could already be burned before you notice the heat at the shell.

 

[lukef]

Hias9, thankyou. The documentation seems to indicate it didn't include one as it was an option but to be honest I guess I should wire it in and see, the wire is part of the harness and does come out of the motor. Looks like that will be my safest bet and install one if not already in there

 

[hias9]

Just measure resistance between the white and the black wire. How much Ohms does it show?
Qs205 usually comes with a KTY83/122.
Can you configure the temperature sensor on your controller or does it require a specfic temperature sensor?

 

[E-HP]

Just measure resistance between the white and the black wire. How much Ohms does it show?
Qs205 usually comes with a KTY83/122.
Can you configure the temperature sensor on your controller or does it require a specfic temperature sensor?

If it's a standard 10k thermistor, then 10k ohms at 25C. Higher or lower based on the actual temp (it will change if you touch it, due to body heat).

 

[hias9]

Why should it come with a 10K NTC?
According to QS it comes with a KTY83 which is a 1K PTC.

Just measure resistance between the black and white wire.

 

[E-HP]

Why should it come with a 10K NTC?
According to QS it comes with a KTY83 which is a 1K PTC.

Just measure resistance between the black and white wire.

That would likely be 1k ohm at 25C

 

[DogDipstick]

2$ Ea.

Lol.