ESC timing and programing

[Paul Williams]

I am confused, although my knowledge base has increased largely regarding electric flight one thing still confuses me. The timing options on ESC and motor poles. Can some one explain how I can tell which option I should use and how to find out what my motor poles are please. What happens if its not set correctly?

[ken anderson.]

hello paul- send for timBo.............

 

  ken anderson.......

[PatMc]

In general terms - a most inrunners & low kV outrunners should have "low" timing; medium kV outrunners medium timing; high kV outrunners "high " timing.

If the wrong timing is used the current will high for the same rpm with any given load. Some high kV outrunners or medium kV ones running a small prop at high rpm will not run smoothly & may give a "backfire" which can loosen a prop drive or damage a gearbox.

To find the number of poles you would need to count the magnets which isn't usually possible with an inrunner. I think all or most inrunners have only 2 poles & most outrunners have 14 poles.

[Erfolg]

Paul

 

With regard to timing, it does not seem to be a critical setting, in general. My first ESC, had the options of Hard, Soft and a few other settings. I phoned the supplier for advice, who did not know either.

 

I set the controller to soft timing and it ran a HET 30/15 with not trouble. I noted the amps and watts, I then reset to hard timming. As far as I could tell with my limited test equipment, Watt/amp meter, there was no difference. With more sensitive and accurate equipment with a standarised power supply, I could have registered some differences.

 

I have purchased a motor and ESC which were supposably from the same manufacturer. A Tornado inrunner with a Tornado 40 amp ESC, which would not run, what ever the setting. Yet the same ESC drove a outrunner quite happily and a cheap Towerpro ESC drove the  inrunner.

 

I have read that hard timing is needed for inrunners or other high Kv motors and soft timing is used for outrunners with low Kv.

 

I have only 9 ESC and motor combinations, so I am no expert. Most seem to run well what ever I do.

 

Erfolg

[Tim Mackey]

Most Outrunners  prefer Hard / High timing (20-30 degrees) and most ESC's work fine with midrange timing on outrunners

If you find that the ESC loses sync (squeals) when the throttle is advanced rapidly,…. then increase the timing to hard or even very hard.

Harder timing also increases rpm and current draw, but reduces efficiency

 

Most  Inrunners prefer Soft /Lower (2-5 degrees).

 

You can use harder timing for more power from Inrunners if you want to, with higher amp consumption - Hacker suggest up to 5 degrees for normal use for instance.

As PatMc said, 2 pole setting usually works fine for inrunners, and the magnets on an outrunnner can often be seen through the front casing as you rotate the "bell".

 

PWM is the Frequency.

Outrunners generally prefer lower PWM

Inrunners typically prefer higher  PWM (up to 32kHz).

[Erfolg]

Seems my memory has failed, yet again.

 

 

What now interests me, is what is timing. From what I have read (I think). Is that the ESC measures back EMF, on a non powered coil of the motor. From this the ESC determines when this value approaches an optimal value (I guess the chip does a diffential calculation).

 

If this is,  does timing reffer to setting a value of when the next coil is to be energised?

 

I have seen a trace on an oscilascope (in a magazine), which was showing a square wave form. At the time I thought no more, than that the transitors were switching the current on and off. At that time i was really interested in, was, is it or  did it  appear to be AC or DC supply. I seem to conclude that it was AC, in that thrree appeared to be a negative value of equal value but opposite to the posative value (not sinusoidal as per text book, but a square wave form). Where as if DC I expected to see effectively all posative values, with the ESC acting as a synthetic comutator. So I concluded AC.

 

I did not think about timing. Yet it doe s seem to fit with Timbo, in that if you have lots of magnets, there will lots of cycles of emf to measure per rev. I would guess on that basis you would need to switch current to the coil a bit earlier, I guess on the same type of thinking of the advance retard on car IC engines.

 

This seems a topic for Ron van ??????, he has a Phd in this sought of thing!

 

Erfolg

[Tim Mackey]

Ron van sommerman or whatever he was called, is no longer a member of this forum

[Paul Williams]

Thanks Guys

[Erfolg]

Timbo

 

It does annoy me when people, carelessly use sought for sort.

 

Anyway, how do you know when a person no longer uses the site?

 

It is a great pity that the magazine does not have a electric/electronic section in the magazine. Even if only occasionally.

 

It is a regretable that those who do know and are members of the web site, are not minded to comment. There was certainly a Proffessional Engineer who finally put the record straight regarding the relevance of Ohms Law and how to apply the concept and its limitations, you also had a lecturer? from Southhampton University post once. Many (myself included), think we know somethings, which are often only partially true or incorrect.  They could for example produce an artical on the use of CAD in electronic design, how connctions are rubber banded and the curcuit functionality is tested within the software.

 

It is only an idea but it does seem that there are a lot of minor issues we all have with electronics/electrics. Knowing how conceptually things work often helps in providing the answer to something such as the timing issue etc. 

[Tim Mackey]

Well I know that RVS has left.

Some members simply stop posting, and move on /off whatever - for a multitude of reasons, and others decide to just leave the forum because of other reasons - sometimes they tell us they are leaving voluntararily ( such as Gemma ).

Others are barred and deleted from the site through failing to abide by the few rules which we have in place - and then we, as site administrators obviously know they have left.

I will leave it to you to decide which category Ron V S fell into

Edited By Timbo - Moderator on 30/07/2009 09:56:36

[scott cuppello]

Posted by Erfolg on 29/07/2009 11:38:09:

Paul

 

With regard to timing, it does not seem to be a critical setting, in general. My first ESC, had the options of Hard, Soft and a few other settings. I phoned the supplier for advice, who did not know either.

 

To be honest, you really do need to pay close attention to this, it's true that some don't really respond to either, but increasingly extreme low to high kv motors are appearing on the market, which DO respond to motor timing, some in spectacular fashion.

 

Let me give you some recent examples Iv'e recently tested;

 

1 - E-Flight Power 160, 10s spinning an 18x12 prop, low timing gave 2400w [can't remember the amps now], but, high timing brought the model to life, giving 2800w, BIG difference.

 

2 - Cyclone 64mm Fans, with in-built in-runner motor, will give around 500w on low timing, more like 700w on high timing.

 

3 - Turnigy 350kv 50-65 motor [horrible motor], on an MA 16x8 three blade prop on 6s, low timing gave 49A 1050w, high timing gave.....wait for this.....1400w, 68A!!

 

This is just a few examples, bottom line is that ESC's are only going to offer a broad range of timing settings, it's therefore essential that the set up is always checked, either way, you could either by lossing lot's of power, or over-amping the motor.

 

I can tell you that one of the most common faults on motors returned to us for testing [aside from the #1 fault....poor soldering], is timing set incorrectly.

 

Edited By Scott Cuppello - BRC on 30/07/2009 10:14:19

Edited By Scott Cuppello - BRC on 30/07/2009 10:16:56

Edited By Scott Cuppello - BRC on 30/07/2009 10:19:57

[Tim Mackey]

Erfolg....Scott is right - and also remember that if the timing is not set correctly for a particular motor, then the motor could be jerky, stutter at start up, and generally nnot respond smoothly to the ESC throttle commands. I always experiment with both timing and Pulse Width Modulation ( where available ) to find what suits my set up best - sometimes its a compromise between power /smooth running and so on.

[Erfolg]

Scott/Timbo

 

I am sure in total or in part you are correct.

 

But Why?   Without some understanding on how the ESC actually works, for me it is difficult to know what in principal I need to do in any particular situation. With a basic understanding it becomes possible to formulate a "set of rules/rule of thumb" for guidance.

 

A simple example of understanding and benefits, would be adding carbon to steel. It became accepted that adding more  carbon from  a low carbon content, increased hardness. But Why? Once it was worked out that the carbon and steel had a certain crystline structure and a phase change took place on heating and cooling etc. The doors opened into the further manipulation on a knowledge based  programme of developments of alloys etc., The ritual was replaced by understanding.

 

I accept that your wide experience in this field enables you advice with authority. Yet it must be better to educate us in the basic principals of what the ESC does and what the are the motors needs to operate and be effective.

 

My experience suggests that it often does not seem to matter. Yet if I knew more, I may understand why my cases are insensative and be able to  both select equipment to ensure sucess and access any problems I might encounter.

 

My concern is that I know from personal experience there were at least two seperate suppliers who could not tell me what the setting should be and the second recommended that i try another  (different make) speed controller as the one I had purchased from them did not seem to work with all there motors.

 

Erfolg

[PatMc]

Posted by Erfolg on 30/07/2009 09:45:20:

Timbo

 

It does annoy me when people, carelessly use sought for sort.

 

Anyway, how do you know when a person no longer uses the site?

 

It is a great pity that the magazine does not have a electric/electronic section in the magazine. Even if only occasionally.

 

It is a regretable that those who do know and are members of the web site, are not minded to comment. There was certainly a Proffessional Engineer who finally put the record straight regarding the relevance of Ohms Law and how to apply the concept and its limitations, you also had a lecturer? from Southhampton University post once. Many (myself included), think we know somethings, which are often only partially true or incorrect.  They could for example produce an artical on the use of CAD in electronic design, how connctions are rubber banded and the curcuit functionality is tested within the software.

 

It is only an idea but it does seem that there are a lot of minor issues we all have with electronics/electrics. Knowing how conceptually things work often helps in providing the answer to something such as the timing issue etc. 

 Erfolg,

Are you being ironic in pointing out the wrong use of a word then peppering the rest of your post with misspellings ?

Glass houses & stones etc.

[PatMc]

Scott,

I'm not sure what your examples are meant to prove.

All you're saying is that hard timing increases the power consumed by the motor/load in each example given. The same would apply in the case of an ic engine if it were run rich but the rpm would drop.

[scott cuppello]

I am not an electronics expert [although the business owner has a degree], and don't profess to be, my job is PRACTICAL applications of electric flight.

 

In short, motor timing should be checked with every installation, as you have found, some ESC's simply will not work with some motors, some motors will only work on 1 timing, and as you can see from my earlier post, you can use this to your advantage...example;

 

I have stuck 2 x Cyclone Red Velocity 64mm fans in the SU34 Fullback, now, the battery tray is designed for 1 x 3200mAh 4s, I a have modded this to accept a 4000mAh 4s, as far as I'm concerned, as much extra weight as I'm willing to add to an excellent airframe before I ruin it's flight characteristics. Now, if I ran both of these fans @ high timing, combined we are talking 90A.....this is where you can take advantage of timing to DECREASE amps for sensible flight times, so, by running the fans on low timing, we are now talking a managable 70A [I can live with 1kw of power on a 3lb model!]....I would rather have a slightly slower, pleasant to fly, light airframe than a missile that flies for 2 mins and wants to tipstall.

 

As you can see from this little example, and the ones above, it's simply a must to at least check the motor timing before flying, and is another example of the need for a watt meter.

Edited By Scott Cuppello - BRC on 30/07/2009 13:07:05

Edited By Scott Cuppello - BRC on 30/07/2009 13:08:35

[scott cuppello]

Pat......the examples are meant to prove that motor timing settings are not to be ignored?!?!

 

And as the rpm's are increasing each time....then not really like an ic engine at all then?

Edited By Scott Cuppello - BRC on 30/07/2009 13:06:05

[Erfolg]

Pat Mac

 

The answer is no. It just happened that I was looking at the replies, when it jumped out at me. The wrong usage of a word, that is. I do know I should read the posting and check for grammar, punctuation and spellings. Yet I do not. Why? A mixture of laziness and wanting or needing to get on with other things.

 

When I worked, every memo, would be carefully checked, for content, tone, grammar and spelling. Now that discipline has gone, as i now know that at best anything which I write is taken with a pinch of salt and it does not matter.

 

Yep pretty lazy and very sloppy. Plus low key board skills, Sorry Patmc. Even now I am not sure that I will try harder

 

Erfolg   

[Erfolg]

Scott

 

I would guess that you are a Jenson Button or Michael Schumacher of this world. In that you are able to see the practical effects of changing parameters. As such a degree is not required, other skills are.

 

From my perspective as an ex engineer, knowing and understanding the principals of how things work, helps me make sense of my world and provides a bench mark against determining what actions I should take and when etc.

 

I certainly do not want an explanation which involves pages of mathematics, detailed theoretical discussion. It is not fun these days and the others by and large would be bored stiff. Yet all of us can and do grasp, simple concepts and this is what I would like. Yet on electric flight we see very little published on these matters. I am not after details of a manufactures circuits, just simple explanation of what happens and why. A guide to what would be ideal would help also.

 

I am not critical of you or any other contributor to the thread, yet recognise that you are to the end of the supply chain where you can ask the manufacturer, in principal how does it work and what is the ideal.

 

To be frank, I have not got a clue, yet still have an intellectual need to understand. If we take the steel example, if we keep throwing more carbon into the melt, there are many downsides to this thought process "oh it will become really hard, wont it".

 

Erfolg

[scott cuppello]

Oh, I think you flatter me...thank you anyway...the way I see it that as a flyer, who also works in modelling, you simply learn a lot when your hobby is also your job! We do like to experiment with many different types here, with the staff flying every type/size of electric model from shockie to large scale warbird, from high wing Cub's to giant scale plyon racers, some of the staff fly petrol, turbines and helicopters.....combine all this with customer feedback, and you are bound to pick up a thing or two.

 

 

[Paul Williams]

Please you guys, the subject matter!!

looking through the threads I have read the effects of timing don't really make any difference to it is critical, are we saying test every set-up or forget we have options. I see the point of reducing the amp flow so a useful flight time is acheived but is this causing long term damage would you not be better off sourcing the correct power to weight ratio in the first place. One thing I do agree with is the need for some knowledge so choices can be made with a better confidence.

[scott cuppello]

Posted by Paul Williams on 30/07/2009 15:58:03:

Please you guys, the subject matter!! - WE ARE ON SUBJECT!

 

looking through the threads I have read the effects of timing don't really make any difference to it is critical, are we saying test every set-up or forget we have options - YES, TEST EVERY FITMENT.

 

. I see the point of reducing the amp flow so a useful flight time is acheived but is this causing long term damage - NO, DAMAGE TO THE LIPO WOULD BE CAUSED BY USING HIGH TIMING IN THIS INSTANCE

 

 would you not be better off sourcing the correct power to weight ratio in the first place - IN AN IDEAL WORLD......IT'S NOT AN IDEAL WORLD.

 

One thing I do agree with is the need for some knowledge so choices can be made with a better confidence. - IT'S NOT INFO THAT'S NEEDED, CHOICES ARE ALMOST INFINATE [NUMBER OF MOTORS x CHOICE OF KV x NUMBER OF ESC's x OPTIONS OFFERED ON SETTINGS....HOW MANY MILLIONS!?]....... IT'S A WATT METER YOU NEED.

 

 

 

[Tim Mackey]

Watch out peeps, Scott is shouting now

[scott cuppello]

Oh, I forgot about this internet shouting thing....just look like caps to me.....

[Paul Williams]

Sorry I shall go out into the garden and eat worms,

When I said knowledge I was refering to what the timing does on a technical basis in other words how it works.