Welcome to Multi-Rotor UK. Please login or sign up.

Thursday,April 09, 2020, 22:03:50

Login with username, password and session length


09 Apr 2020 19:33:13
All shipping from china has gone up, so much that some of the heavier goods are now only sent by sea  :rolleyes:
09 Apr 2020 16:54:13
Anyone else noticed BangGood adding a couple of quid as delivery charge to each item?
27 Mar 2020 21:41:51
We've been in self imposed lock down for last 2 weeks!!! March is going so slowly............................ More time to Whoop around the garden  :D
27 Mar 2020 21:30:37
Self isolation since tuesday already feels like a month  :wack0
27 Mar 2020 12:06:05
YEEEESSSS, we finally have a viable excuse for locking boris johnson in a room by himself were he cant do anymore harm
24 Mar 2020 18:45:40
Don't bin your Thingiverse account you have lots of good stuff there. It will all quieten down in a few months.Just ignore the muppets as normal.  :D
24 Mar 2020 13:45:57
wow Im so binning my thingiverse account.... the amount of knobs hashtagging "covid19" on their just to get hits is just ridicules
18 Mar 2020 05:49:28
how do we get to general discussion chatroom?
17 Mar 2020 11:10:32
@badger1, When my quad got all muddy, a quick rinse under the hot tap, avoiding the electronics, got the worst of it off, then strip down and clean, quick repair to the VTx, it's all good again ~~
  • Total Posts: 198025
  • Total Topics: 19979
  • Online Today: 59
  • Online Ever: 530
  • (Tuesday,June 26, 2012, 08:34:46 )
Users Online
Users: 1
Guests: 47
Total: 48

Theme Changer


3d - Printworx

Printing 3d Forum

BLHeli questions

Started by annikk.exe, Wednesday,June 10, 2015, 09:02:30

Previous topic - Next topic


Marty kindly lent me his USB programmer stick, and I';ve been looking at the Blheli configuration suite and wondering what options to mess around with.
Is there a good explanation anywhere online of what all the parameters do?

For example, what does Motor Timing do?  I googled about it last night and found a forum post that states it';s related to the "phase angle" of the motor within the magnetic field.  So it';s sort of like the spark plug timing in a car engine.
I tried "medium" (the default) and "medium-high" so far, and to be honest I';m struggling to notice any difference.
What sort of effect would I see from changing this?  Will the motor spool up faster in certain positions, or run quieter?  What sort of test methodology can I use to check the effects of changes to this parameter?  (Thrust test maybe?)

There';s also various mentions of "demag".  What is demag? :>

Any info about this stuff would be awesome!


As far as I can recall, motor timing relates to the number of cores in the motor?  So higher number, the higher timing rate it will support.  General advice was always stick to low-medium!
Blog: http://ajwillis303.wix.com/stuff
The spiritual home of fpv large
Keep it emax, capiche?
Hardware? sure, I got hardware!


What';s a "core" in the context of motors?  Is that part of the stator?


poles i think he means.

that';s about as much as i know :laugh:
Point and click.

Monkey see, Monkey do.

Marty McFly

Hi Luke,i no you have to put PWM/Frequency/Damped to damped light for one shot to work,Marty and the borrowed doggie, :scotland:


every 250 setup i';ve seen with blheli uses medium/high timing and demag low or off, but mainly low.

this is what i found re timing and demag

Commutation timing can be adjusted in three steps. Low is about 00, mediumlow 80, medium 150, mediumhigh 230 and high 300.
Typically a medium setting will work fine, but if the motor stutters it can be beneficial to change timing.
Some motors with high inductance can have a very long commutation demagnetization time. This results in motor stop or stutter upon quick
throttle increase, particularly when running at a low rpm. Setting timing to high will allow more time for demagnetization, and often helps.

Demag compensation is a feature to protect from motor stalls caused by long winding demagnetization time after commutation. The typical
symptom is motor stop or stutter upon quick throttle increase, particularly when running at a low rpm. As described earlier, setting high
commutation timing normally helps, but at the cost of efficiency.
The demag compensation is an alternative way of combating the issue. First of all, it detects when a demag situation occurs.
- In this situation, there is no info on motor timing, and commutation proceeds blindly with a predicted timing.
- In addition to this, motor power is cut off some time before the next commutation.
A metric is calculated that indicates how severe the demag situation is. The more severe the situation, the longer power is cut off.
When demag compensation is set to off, power is never cut.
When setting it to low or high, power is cut. For a high setting, power is cut more aggressively.
Generally, a higher value of the compensation parameter gives better protection.
If demag compensation is set too high, maximum power can be somewhat reduced.

if you wanted to explore the settings and have too much time on your hands then set up a thrust meter and current meter to gauge the efficiency of your motors, esc and prop set up at different timing and demag settings.
Round By Round Qualifying and Finals For All.

it just makes sense