CA doesn't take account of "assist start level"

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poeleafrire6   1 µW

1 µW
Posts: 2
Joined: Apr 01 2020 7:30am

CA doesn't take account of "assist start level"

Post by poeleafrire6 » Apr 01 2020 9:25am

Hello,

Here is my configuration :
Tandem : 440 lbs (= 200 kg)
Battery : 52 V ; 23.8 A.h
Controller : 40 A (battery Intensity)
Motor : front MAC 10t ; 26"
CA : CA3-14
CA Setup Utility : v1.54

In preset 2, I set my "assist start level" at 400 W but actually (read on the CA), "assist start level" is nearly 800W. (That is my problem).
In preset 3, I set my "assist start level" at 1000 W actually (read on the CA), "assist start level" is nearly 1000W.

When I feel that I pedal at 90 rpm, the CA show 90 rpm.
I think that the sensort see the 12 magnet of the magnetic disc because in 1 turn of crank, i can see the LED of the sensor light 12 times.
If I set the "Power limit" at 400W actually (read on the CA), the power is limited to nearly 400 W ; so I think that the CA is able to regulate this configuration.
I tried to swap the sensor, but nothing changed.

Here is my "CA Setup Utility" setup :
Diapositive1.JPG
Diapositive1.JPG (77.21 KiB) Viewed 124 times
Diapositive2.JPG
Diapositive2.JPG (91.44 KiB) Viewed 124 times
Diapositive3.JPG
Diapositive3.JPG (68.33 KiB) Viewed 124 times
Does anyone has an idea of how to fix it?
Thanks you in advance.

I am a new member, this is my first post, i hope I am in the good section.
By the way, I am French, i hope my english will be correct.
Last edited by poeleafrire6 on Apr 03 2020 8:25am, edited 3 times in total.

AngryBob   100 W

100 W
Posts: 234
Joined: Jul 10 2019 4:37pm

Re: CA doesn't take account of "assist start level"

Post by AngryBob » Apr 02 2020 1:17pm

This is likely a question best directed to Grin tech support.

A very consistent response to CA troubleshooting request is to go through the ENTIRE 30+ page manual, from page 1, and make certain ALL settings are correct, as many of the early, basic settings have an effect on the later, more advanced settings. GO THRU ALL THE SETTINGS is repeated many times by the guy who wrote the manual.

Your English is quite good, however your usage of the phrase "in reality" is unclear. You make a setting of a certain value, and the ACTUAL value is different, - measured or determined in what way?

That method of measurement is what makes the number a reality instead of just a feeling.

I am assuming you got the numbers from instrumentation of some sort, however clarity in these issues is important. If this is a readout from the CA itself, since this is the hardware in question, then you ideally need some other way to measure or at least quantify the actual assist level wattage for the various settings. Zero is a pretty easy value to determine, but other numbers become more difficult.
"Not being treated like a dumb dick is one of the incentives we have to become less stupid." - Balmorhea.

poeleafrire6   1 µW

1 µW
Posts: 2
Joined: Apr 01 2020 7:30am

Re: CA doesn't take account of "assist start level"

Post by poeleafrire6 » Apr 03 2020 8:41am

Thanks you for your answer.

Okay, after reading your post, I have send an email to Grin tech. I will share their answers with you.

I had already read the CA Grin tech manual and the Unofficial guide from Teklektik (a member of this forum) and I had chek every setting.

Ok, I corrected my previous post in blue. By "in reality", I wanted to mean : actually (read on the CA).
I also converted the weight in lbs

After the coronavirus, I will check the powers with a multimeter calibrated from work.

I think that the value on the CA are nearly correct (something like +/- 20%) because :
I made some tests on an exercise bike :
I can hold 400 W for a few minutes
and 700 W for a few seconds
I made some tests on a regular hill (I was solo on the bike)
If I cut the power on the motor and use my legs :
I can hold 13 mph for a few minutes.
and 21 mph for a few seconds.
I tried to simulate this hill on ebikes.ca motor simulator :
hill test ebikes_ca motor simulator.JPG
hill test ebikes_ca motor simulator.JPG (119.9 KiB) Viewed 74 times
At 13 mph, the power at the wheel is 325 W, not far from 400 W
At 21 mph, the power at the wheel is 675 W, not far from 700 W

AngryBob   100 W

100 W
Posts: 234
Joined: Jul 10 2019 4:37pm

Re: CA doesn't take account of "assist start level"

Post by AngryBob » Apr 03 2020 6:41pm

That is a reasonably good approximation from a secondary data source.

It is important to separate readings from the hardware in question.

Do share the response, I'm kinda curious what the cause is.
"Not being treated like a dumb dick is one of the incentives we have to become less stupid." - Balmorhea.

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