New Batch of PCB's

I'm thinking of converting the PowerPCB so that the 24V outputs and the DC/DC converter get their power directly from the battery and the Switch only switches the 5V for the Teensy. Then there won't be so much current going through it.
But then it is no longer a complete switch-off, but I think the power consumption should be low?
 
PowerPCB with 2-Channel Relay. So far still without a switch for the 5V.
 

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I think it's better to first test your mower in normal mowing condition before order new set of PCB.
In a normal robotic mowing , you never cut more than 1 cm of grass and adjusting the max mow power to 60W is larger enough.
At 60 W the firmware automatically shut down the motor for the next 1 minutes and this is OK for the start of the season.
After 6 or 10 hours mowing , normaly mower cut only 1 mm of grass, power is less than 10W and mow motor rotate at low speed so it's 0 noise and the battery life is *2 .

So please first try to finish the charging station and use the mower for 1 week in full auto mode to see what 's append. ;)
 
I'd love to do that if things didn't keep breaking, it's not my talent it seems :)
 
Bernard, you added an heatsink on Q4, is it the only components who could heat more than the otherones ? I think about welding thisone on the back of the PCB and add a heatsink. What about the other components ?
Sascha, maybe your talent is to help us to know the limits of the components and how to resolve problems. My tests for now ar not really helpfull... but yours are. Combinated with Bernard's advises, thanks for this.
 
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Yes, yes, I'll test everything that can break, then you won't have to do it again :-D
Luckily I still have a few PowerPCBs, but I don't feel like soldering them.
 
I'd like to help in tests and have finished building now, but I'm so busy....I'm late.
If I correctly understood, the software will stop the mower if your motors needs more than 60W. It shouldn't heat anymore in this case, should it ?
 
I think the Q4 is enough, all the current from the motors goes over it.
You have to set it in the PfodApp under Settings -> MOW so that it can have 60W max.
 
LaurentS said:
I'd like to help in tests and have finished building now, but I'm so busy....I'm late.
If I correctly understood, the software will stop the mower if your motors needs more than 60W. It shouldn't heat anymore in this case, should it ?
Click to expand...
Mow Motor Max power is very important.
This setting is used to adjust the speed and protect mow motor from overload.
At 50% of the value the motor rotate at minpwmspeed to have more battery duration
At 79% of the value the motor rotate at maxpwmspeed grass is high.
At 80% of the value the motor rotate at maxpwmspeed and if mower mow bylane the speed is reduce , or if mower run in random it start to mow in spiral.
At more than 100% during 1 second the motor is stop for the next minute and mower continue to move.
 
My mower has now been in the charging station all night for charging, but it is not fully charged. The battery is now at 27.1V, ~2.3V are missing.
The charger charges with 29.9V and 4.2A.
I think 2.3V are lost somewhere.
 
Normally it's 29.4V max.
Into setting battery :
Stop charge if sense below : adjust to 0 to never stop the charging process (Only 10 Hours timeout stop the charging).
Now increase the start charge if voltage below to max possible to start again the charging process and take a look at the led locate on charger (red in charging green charge finish).

Using a Voltmeter check the real bat Voltage and adjust #define D5VoltageDrop to correct value to have the real bat voltage into arduremote.

My charging stop this night at 5H30 after 10 Hours at Charger:29.2V Battery:28.78V and Current at 0.17A

I actually follow all the process of discharging in station by recording everything using Pyardu.
 
V_Bat is connected on INA226 and i don't know if it's OK to have VBS and no VCC at same time on INA226.
Normaly the only voltage drop is the D5 Diode and is constant.

Maybe The next PCB need to use the Teensy ON/OFF function and disconnect everything when in sleep mode.
 
O.K.. I use the INA139 as a single chip. Reichelt will only have it again in 6.2023!!! But you don't have these restrictions. You have to be good at soldering for that.
 
Maybe we should really think about the PowerPCB again and see if we can't simplify it a bit more.
With my first conversion, I simply had a voltage divider for the battery voltage, which worked wonderfully and the volt values were also correct. When the battery was full, a green LED came on and when it was time to go home, the LED started flashing. I didn't have a shutdown, but it was only the MEGA, which doesn't consume that much.
My mower has been in the charging station since yesterday evening and has not been fully charged. If I charge the battery directly with an e-bike charger, it is full after just under 2-3 hours. But there is a different charger attached to the charging station.
And now I'm only at 26V again. Not enough to get going again.
 
It can't work with the R100 on the INA226.
I have charged mower more than 10 time in auto mode without any issue.
Charging duration only depend on your charger and battery capacity.

For power PCB you can do the same way as the initial DUE PCB but how to know the 3 motors (or 5) sense ??
 
Yes, that's what I thought, I have first to change the shunts and the capacitor, then I think some of the errors will take care of themselves.
The current measurement with the INA must be done.
I will now wait for the missing parts, I hope they will arrive this week.

I can't really think of anything that could be improved or optimised,
I can't really do much with fewer components.

But I am open to ideas and suggestions.
 
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