how to program a sevcon gen4

[jollmo]

As I can see, I'm not the only one beeing confused about the "nominal voltage" setting in sevcon's dcf files.

I own govecs go S2.4 and S3.4 scooters, which I managed to make a lot more driveable via altering values through DVT customer.
Both, the 2.4 and the 3.4 are more or less identical scooters.
The differences are: 2.4 is a 50cc equivalent, has a Mahle Letrika AMK6143 motor and a sevcon gen4 size 2 controller, the 3.4 is rated as 125cc, has a Parker SME1422815 Motor and a sevcon gen4 size 4 controller.
Both are equipped with 72V, 40 or 50 Ah batteries.
In the config file for the 2.4 the nominal voltage is (as expected) 72V
in the config for the 3.4 it shows 80V.
Same battery, 72V...
Anybody has an idea why?
Will it make any difference if I change the 3.4 to 72V as well, as the battery is the same?

I'm a bit out of ideas right now...
Thank you all for your help!

 

[flob]

Hi,
i do not know why either.
I would though change to correct value and make sure that all other related values like low and high voltage cut offs be correct values too.
Just because i want to have things right...
flo

 

[flob]

COULD IT BE THAT SIMPLE?
Well it is said that the problem usually sits in front of the device...

After getting some replies from the vendor, stating for example that Motenergys inductance of 0,10mH translates to Ls 90 in the sevcon i was left again puzzled of why ii do not see full power.
A phonecall with a friend led to suspect throttle settings.




May i have simply interpreted the manual wrong?
I was under the impression that i would have to set the throttle voltages less than what throttle setup routine gives out.
with the maximum allowed voltage only to prevent faults.

So am i right to assume i have to change Maximum allowed voltage (2.nd pic) from 13 down to 11 instead? (opposite of what i thought)
A quick calculation, assuming everything linear:
13/11 x 24KW ...about 28kw ad one more for partial charge and one more for temps being pretty low and we would arrive at 30KW right in the ballpark.

Any thoughts about that?
flo

 

[darseygodwin]

The throttle map is meant to program a curve. Sometimes you want a torque demand to be linear with throttle twist, other times you don't. Some want more throttle sensitivity at low speeds and others want that sensitivity at the top end. Those values create a curve. This isn't the screen that does this - there is another with a few different points in the curve that works exactly the same as your torque curve. You'd want to map 0% throttle through a little bit of the twist so you don't accidentally have a light breeze walk it off the kickstand. Similarly, if you thought your max twist wasn't getting 100% throttle, then reduce the peak twist voltage value that corresponds with 100% demand.

You really need to take a trace. Map your TPDO's to include things like throttle %, Iq target, and Iq actual. With those three values alone, you could see if the target torque's current matches the throttle or is slow to respond (pointing to the ramp rates), or if they do match, but your Iq actual is wildly different than your target, then that's another problem. Maybe they do match, but you don't get your desired peak current - then that means one of many factors are limiting the torque target. Maybe it's a torque map, battery-power map, temperature map, short or long term current limit, BMS fault limit (if BMS was pre-programmed and canbus connected) etc.

When you're on the main DVT screen - (H) button is for the "helper" screen, which you've been using. The (wheel) button is to monitor live values. Do that one. This screen shows you the values programmed to your TPDO list, programmed in the helper window. There is a Google-able sevcon app note explaining how to map your tpdo's and why. When they're set, and you're on the monitoring screen, you can select a location to save excel outputs of the trace, or simply view them back immediately as a graph of current values vs time. not all of the tpdo's go to the immediate trace recording, but they all get shown live and recorded in the excel file. Mapping your throttle, target torque, Iq demand etc, would tell you a lot. You can temporarily set your peak allowable current to something crazy low, like 5A, then roll on the throttle to see if you hit 100% demand.

 

[JackLee]

Hello,
I've been trying to dive deeper into the topic of "Sevcon programming" for a few weeks now. A very rocky road unfortunately. But I have managed to run several engines with it. But currently I have a question : Is it possible to realize a "One Pedal Drive"? So that e.g. from 20% of the gas pedal value 0A are sent into the motor and below recuperation? Have not yet found a way to realize that.

 

[Austin]

I've never used anything but a $99 USB to CAN adapter for all my sevcon programming.

Even Sevcon doesn't use the handheld thing.


Getting the program into the sevcon is 0.001% of the difficulty in programming a sevcon to work WELL with a motor. If this part seems difficult to you, you're in for a long trip down frustration lane, and it's no fault of the controller or whoever sold it to you, it's just the nature of setting up an ultra tuneable controller like a Sevcon Gen4.

Hey bud I'm trying to program a sevcon power pack 650a controller... we're can I find the dongle cuz I'm having trouble finding one or can I make one.. I bought one for a Milla pak that came with the disc but it won't connect to the power pack

 

[Austin]

Do you still need the sevcon PC software along with a USB to CAN for programming?

Will it program a sevcon power pack

 

[sanfox]

Any body use dvt comand during bootloader mode "save EEPROM" to downdoad firmware from controller (save dld)?

Command -- Alias -- Description
save -- Reads data from a memory space and stores it in a file - assumes controller is in bootloader

SYNOPSIS
save nodeid section binfilename

DESCRIPTION
Uploads from the specified section on node nodeid to binfilename. Section can be one of
dsp - DSP slave on espAC (inc Dialbo/Chinook)
eeprom - EEPROM
xc164-int - Host XC164 internal flash
xc164-ext - Host XC164 external flash
at49bv-ext - Host 2812 external flash
dsp-zeffer - Host 2812 internal flash
flash-config-a - Host 2812 flash config A sector
flash-config-b - Host 2812 flash config B sector
display - CANopen display flash

 

[sanfox]

I am trying to get married working dcf file for induction motor, (which works well with DLD UK0328.04 which I have not now), with DLD UK0319_23.
After uploading dcf file to DLD UK319_23, I have 9 errors.

It's not so critical, after some pases they was solved.
But now I have strange faults according to index 0х5044 and index 0x4f41 (Internall error apparently attached to previus index).
Range check object (0x5621) tell me that I have Range check failed object 0x4630_3 (Encoder type).


So I go to Encoder configuration and check encoder parameters, but I don't find mistakes here!

I begine to test encoder functionality by externall rotation and it works well.

Where the way to light in this situaton?
Sevcon gives faults without reason?