IDC limits via canbus ?

[PoloLbricolo]

Hi all,
Finally moving forward with my project

I'm looking to set IDC min and IDC max via a canbus message sent by my BMS, that way BMS is happy and not opening the contactor when under load because it sees too much power going in or out of the battery pack.

I'm using a SDU logic board V6 runing the 4.97R firmware.

How do i setup these can messages using the web interface ?

[johu]

You have to use custom command because parameters don't have the CAN facilities. So

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can rx idcmin a b c

a, b, c being bit offset, bitt length, gain (usually 32)

[Zapatero]

If you got it working please let me know if this works smooth for you. Mine work but the limit is very very harsh and the whole car rattles and "clonks".

Thanks!

[johu]

Yes I'm still trying to understand that. Basically in Touran which has the very same drivetrain and same parameters (the only difference was throtcur, which we then matched just to check) it works totally smooth. Even parameters that are completely undriveable for Philip just give me a little wiggle in Touran. The only obvious difference is the car itself. Different transmission + driveshaft to rear and different chassis. Maybe it just reacts more to torque ripple?

[PoloLbricolo]

You have to use custom command because parameters don't have the CAN facilities. So

Code: Select all

can rx idcmin a b c

a, b, c being bit offset, bitt length, gain (usually 32)

where/how should i send that command from the web interface ?

[johu]

at the top where it says "Send Custom Command"

[PoloLbricolo]

indeed, never used it yet. I'll try this and report how it's going

Thanks !

[Peter]

If its any help I am working on reading idc via CAN then adjust CAN value of throttle %. Therefore if idc is below a set value I can have max throttle and as the current rises above the set value the throttle is backed off linearly. Thats the theory, so it does not have the effect of shutting down with 'rattles and clonks'. Reading CAN at 1M for speed of response too.
I am sure bms variable can be added to this idea.

[PoloLbricolo]

I got arround to doing it (finally), i seems that the command to send was missing a parameter before a concerning ID.
So the commands i used are :

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can rx idcmax 1301 0 16 32

1301 being the id in decimal (0x515),0 being the bit position, 16 being bit length (2 byte) and 32 the ofset.

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can rx idcmin 1300 0 16 -32

1300 being the id in decimal (0x514),0 being the bit position, 16 being bit length (2 byte) and -32 the ofset as we want idcmin to be negative.

Since i'm using orion 2 bms the data sent is some what diffrent, as you can see in the pictures attached.

Biggest difference is the byte order on the bms side.

After a little testing when going over the max limit is like when the inverter goes overtemp. I can't really do more testing as my car is not road worthy yet (no doors, roof or body panels) and we are in lockdown again..

Cheers
Paul