Motor Temperature

[ccrdave]

anyone using mission control or BLevo to monitor their levo or kenevo while riding can you tell me what is the maximum motor temperature you see please

 

[Stompweaver]

I gave my Kenevo a good thrashing this morning and checked the motor temp, it had got up 116 Fahrenheit in the Mission Control App.

 

[ccrdave]

ok thanks, that's 46c did you notice any drop off in power when it was that hot?
the highest I have seen on mine is 37c and according to the app readings power did drop off a little

 

[Stompweaver]

Yeah I had to convert it into Celsius too as I have no idea how hot 116 degrees Fahrenheit was!

There was no noticeable (to me anyway) drop off in performance at that temperature. Normally the motor temp is around the high 30’s but I only had an hour this morning before work so I went for it hard in Trail and Turbo. My settings in Trail are 50/50 and 100/100 in Turbo. For reference I did 10 miles and 2000 feet of climbing in that time.

 

[Kiwi in Wales]

anyone using mission control or BLevo to monitor their levo or kenevo while riding can you tell me what is the maximum motor temperature you see please

Hi Dave,
After your related post on power loss when the battery is lowish the other day I did a small test yesterday whilst riding back on the road from the pub.

I set the bike to Turbo and road flat out ensuring to keep just below the 25kph mark for the entire trip so the motor was working continuously and wasn’t disengaging to keep the work rate of the motor and battery up.
The distance was just over 7km.
I was at 30% battery level at the start and finished on 5%.
As it is Wales there were a number of ups which worked the engine fairly hard.

Max reading on the battery was 33 degrees
Max reading on the motor was 49 degrees.
We may be able to get @PaoloBLEvo to code in the above output values in the Blevo ride stats. He was able to do this for max motor power and max biker power. So he may be able to do it for battery and motor temperatures?

Both temps dropped quite quickly after I stopped.
The ride took about 16 minutes.
The interesting bit was the power output. I couldn’t get any more than 550 Watts so a loss of 100 plus of what I normally get when I am in Turbo on my 2017 Levo.
Not sure if the lower power output was down to heat or down to the low battery level or down to both. I will need to try the same test on a full battery to see what happens

Hope this helps.

This is how I have my display set up when I am riding.

 

[ccrdave]

Hmm thanks Chris thats interesting quite a power drop i wonder in your case if that motor or low batt causing the drop.
My first test was with about 90% full battery and motor at 37c, i lost about 40-50w

 

[ccrdave]

Oh are you running motor firmware 5.0.4 Chris? Spesh told me the latest motor update improved the performance when the motor was hot

 

[Kiwi in Wales]

To be honest it still allowed me to hoof up the hills and I could not physically feel that I had lost 100 plus Watts as in a sharp drop off of power. The display just showed me the motor was only putting out 550 watts

 

[Kiwi in Wales]

Oops our posts must have crossed.
No still on 4.22.3 battery
4.0.1 motor

 

[ccrdave]

Whats your motor firmware 4? After 4 there is 5 then 5.0.4

 

[Kiwi in Wales]

Whats your motor firmware 4? After 4 there is 5 then 5.0.4

Ok, sounds like I need an update then...

 

[eFat]

Whats your motor firmware 4? After 4 there is 5 then 5.0.4

And 6.0.0... It's interesting that Specialized is still at the 5.0.4. Others Brose had an update a few months ago.

 

[ccrdave]

Any idea what the 6 update did?

 

[Kiwi in Wales]

Ok,
I did another test this morning.
Same route as Sunday.
The battery was at 50% this time. At the end of the ride it was at 25%
It was also a lot cooler than it was on Sunday afternoon, about 5 degrees v 20 degrees

The ride took about 16 minutes.
Max reading on the battery was 22 degrees
Max reading on the motor was 40 degrees.

Interest bit was the Watts again
At the start on 50% battery level I couldn’t get any more than 610 Watts max motor power no matter how hard I pushed it.
At the end of the ride this had dropped to 25% battery level and around 570 Watts max motor power

So it looks like the max motor power output drops on a sort of sliding scale as the battery discharges.

Getting 550 Watts when it is down to 5% is still pretty damn good me thinks

 

[khorn]

I think that there could be an easy explanation to the drop in power output. As your battery wears out, the volts on the battery will drop and therefore providing less power to the engine

Karsten

 

[ccrdave]

I also think the 5.0.4 update was to address this power loss and minimise it

 

[ccrdave]

I think that there could be an easy explanation to the drop in power output. As your battery wears out, the volts on the battery will drop and therefore providing less power to the engine

Karsten

im not so sure there is some pretty good battery management software and firmware inside our batteries. we use a similar technique with our underwater electronics and the voltage is pretty stable almost to dead battery

 

[ccrdave]

I think its more question of heat management, on the early levos when you worked the motor really hard it would cut out, whether that was an intentional design to protect the motor is debatable but when the carbon frames came with a very reduced capability for heat dissipation Spesh had to have a bit of a redesign hence the 1.3 motor and a few firmware updates, and now I think a gentle reduction in power output when the motor is pushed is an intentional way of component protection.
just a guess mind!

 

[khorn]

im not so sure there is some pretty good battery management software and firmware inside our batteries. we use a similar technique with our underwater electronics and the voltage is pretty stable almost to dead battery

From my limited knowledge of the BMS it’s more about protection of the individual battery cells with respect to prevent overcharging, overheating and equalizing. The same goes for the discharge process, protection of the cells, the prevention of the engine drawing too many amps and preventing the cells from getting too discharged. If there is also a voltage regulator I have no clue about but then why can you see the voltage drop in the Mission Control when you are using the battery while riding?

If it is not the voltage drop causing less power, what is it then when it is not temperature related ?

Karsten

 

[ccrdave]

well i think it is temp related, electronics is not my main expertise but I do understand a little about "voltage pumps" not how they work but what they do. maybe the reading you see on mission control is "real time" voltage drop before its "pumped" to the motor.
I am just guessing here mate and my theory could and probably is way off but the tests I have done have been with a full battery and the hotter the motor gets the more the power drops, The latest firmware update to the motor has definitely reduced that drop hence my guess

 

[eFat]

At one moment if you reach the maximum allowed current you can't do anything. A discharged battery will have less voltage and with the same (maximum) current the power output will be less.

 

[ccrdave]

At one moment if you reach the maximum allowed current you can't do anything. A discharged battery will have less voltage and with the same (maximum) current the power output will be less.

agreed but can that be minimised by setting the low battery level warnings to be higher than an actual low battery voltage. so when we get the red lights on the battery the actual battery voltage/capacity remaining is enough to be regulated

 

[eFat]

To have a constant output it would mean that as the voltage decrease the current increase. But if the controller allows for maximum current with a full battery it's not possible. And it's more the opposite, you need a "high" voltage to generate the maximum current so I think everything decreases with the discharge.