NEW - ESC vs ESC

[CrashAddict]

What do you mean by "Non Isolated Governor Output". I struggled with this when I went with a separate BEC because that governor signal is powered by the internal BEC and I hooked it into a device that was powered by the external BEC. It seems to work fine. Should there be some sort of opto isolator powered by the external BEC and not connect that governor output up to the external governor directly? Whenever this is packaged into a Mikado kit with an external BEC it seems that they plug the governor cables into the external governor without any isolation and create a ground loop. Goofy if you ask me.

[HeloMan]

I just got a new Align 500 pro dfc with beastx AR7200. I'm building the kit now. I have a newer castle ice 75. Would you use the cc esc or install the align that came with the kit? I am a new to this hobby ( about a year & a half) and on a steep learning curve. This is a great thread wow what a bunch of info. Thanks. My gut tells me Castle would be a better choice but I really don't know.

[rceccleston]

Originally Posted by HeloMan

I just got a new Align 500 pro dfc with beastx AR7200. I'm building the kit now. I have a newer castle ice 75. Would you use the cc esc or install the align that came with the kit? I am a new to this hobby ( about a year & a half) and on a steep learning curve. This is a great thread wow what a bunch of info. Thanks. My gut tells me Castle would be a better choice but I really don't know.

The Ice 75 would be highly recommended for the quality, features and logging.

The Align ESC's are notorious for flaming up.

[HeloMan]

Thank you for the fast replay. I need all the confidence I can get I'm doing the right thing. What is framing up? I assume it is loss of data packets? Taknks again

[rceccleston]

Originally Posted by HeloMan

Thank you for the fast replay. I need all the confidence I can get I'm doing the right thing. What is framing up? I assume it is loss of data packets? Taknks again

No prob.

Sorry, I meant flaming up...

[hakulhak]

Hi Guys,
so what conclusion or verdict to all of this testing?

[NickBee]

Originally Posted by hakulhak

Hi Guys,
so what conclusion or verdict to all of this testing?

Lots of great info in this thread, most of it over my head.... My "take away" was.... If you like to fly drastically different head speeds during the same flight, get an ESC with free wheeling.

[Iceberg86300]

Originally Posted by CrashAddict

What do you mean by "Non Isolated Governor Output". I struggled with this when I went with a separate BEC because that governor signal is powered by the internal BEC and I hooked it into a device that was powered by the external BEC. It seems to work fine. Should there be some sort of opto isolator powered by the external BEC and not connect that governor output up to the external governor directly? Whenever this is packaged into a Mikado kit with an external BEC it seems that they plug the governor cables into the external governor without any isolation and create a ground loop. Goofy if you ask me.

EDIT : this post is a product of my misunderstanding of the quote, and should be overlooked.

That is just crazy. 2 voltage regs should never be connected because they won't put out the same voltage and will kill themselves trying.

If they are close enough and one doesn't burn then you have the ground loop like you said, but in this application there isn't allot of analogue voltage measurement so it won't be as big of a deal, but still not good.

Regards,

Steve

Sent from Tapatalk using my Inspire 4g through ATT (meaning it's a wonder you can see this!)

[SoftShell]

Originally Posted by CrashAddict

What do you mean by "Non Isolated Governor Output". I struggled with this when I went with a separate BEC because that governor signal is powered by the internal BEC and I hooked it into a device that was powered by the external BEC. It seems to work fine. Should there be some sort of opto isolator powered by the external BEC and not connect that governor output up to the external governor directly? Whenever this is packaged into a Mikado kit with an external BEC it seems that they plug the governor cables into the external governor without any isolation and create a ground loop. Goofy if you ask me.

To clarify some electronics issues.

Yes, the governor 'sense' signal coming out of an ESC (YGE for example) is powered by the ESC's internal power supply.
But the 'signals' on signal wires are always low power, and 'signals' are connected to buffered inputs, which are capable of handling signals from devices having various voltages. The fact that your ESC has its own BEC, and your Reciver/FBL unit having an external power source, does not really matter to the 'signals'.

However, it is a wire, and it connects your ESC directly to your electronics.
And is a pathway for high frequency electronic 'noise' to pass between them.
If you think that your ESC is generating too much 'noise', which is interfering with your electronics. Then consider this as a potential source.

But, the big thing is to make sure that two power supplies are never wired together through the 'red' power wire. In this regard, signal wires are not an issue.

Unlike signal wires, BEC's or Lipo's are capable of putting out many amps of current. Even a tiny voltage difference, could lead to a significant reverse current flow through the red wire, into the device (or Lipo) that has the lower voltage.

Opto's (or Opto Isolators), provide two functions.
1) They isolate the signal path via a 'optical junction' which simply cannot carry electrical noise.
2) They also break the red 'power' circuit. Eg: the red wires on the two sides of the opto are not connected through to each other. Be aware though that the output side of the opto needs some power (via the red wire) in order to re-generate the electrical signal after it has passed through the optical junction.

'Signal Boosters' (sometimes used with ESC's) are simple in-line amplifiers which boost the voltage of the signal on the signal wire. They do not break or isolate the red power wire. It runs straight through. Signal Boosters also require power from the 'red' wire.

[Iceberg86300]

I totally misread that to say that 2 bec's were being plugged into the same bus (red wire red wire). Voltage differences here could cause major damage as explained above. But because the external governor is only getting a signal you just have to make sure it can handle the voltage of the signal (hyperion phase sensor puts out the same voltage to the signal wire as it get s from its power feed.)

Also, creating a ground loop by plugging stuff in is bad, but nowhere near as bad as ground loops on the circuit board near signal paths. This can and does create havoc on the signals.

That's why you'll see allot of job ads for analogue system design, people really need to know what they are doing.

Regards,

Steve

Sent from Tapatalk using my Inspire 4g through ATT (meaning it's a wonder you can see this!)

[SoftShell]

Replying to Iceberg.

Yes - ground loops are troublesome.

But in a strict technical sense, they start happening when two devices (or two parts of one larger circuit) have different 'ground' voltages.

Every wire has some resistance, and when current flows through it, a voltage drop occurs. ESC's are big offenders in this regard, since they run quite high motor currents through the battery leads. This return current through the 'black' battery lead can cause the voltage of 'ground' seen inside the ESC to be higher than 0.0 v (relative to the battery). And it jitters, according to the motor current being chopped on-off-on-off all the time.

This jittering 'ground' voltage (inside the ESC) gets added as 'noise' onto the pure clean signal voltage coming from the Receiver's electronics.
It can also inject 'noisy' currents back into your entire system through the 'ground' wire to the Receiver.

Ground loops are a fact of life. Keeping them small and innocuous is the goal.
Having good wires/connectors/solder-joints between the battery and ESC is the first and most important step in reducing ground loops.

[tracernz]

This is a great thread!

Originally Posted by eylau2005

no it doesn't..in fact there is a question/doubt in 187 either .. in any case I asked 3 questions and not get any answers.... and that is all in ref to great AFW Tony explanation on how it works when it is ON... but doesn't when is OFF... so why there is a switch? how it works when is OFF and When should be turned off. But for the latter you have to know answer 2 first.. I'm afraid only Tony can shed the light on that Have a good day

I see this still hasn't been answered. From my understanding when you switch the AFW function off with your programming card the FET will not switch on and so the freewheel currents will go through the body diodes, passive freewheeling. Have another look at the second diagram in post #3 and you will see the body diodes are shown but as AFW is enabled the FET provides a much lower resistance path for the freewheel current.

[SoftShell]

Originally Posted by tracernz

This is a great thread!

I see this still hasn't been answered. From my understanding when you switch the AFW function off with your programming card the FET will not switch on and so the freewheel currents will go through the body diodes, passive freewheeling. Have another look at the second diagram in post #3 and you will see the body diodes are shown but as AFW is enabled the FET provides a much lower resistance path for the freewheel current.

Exactly right. However it is all a matter of extremely precise timing.

• Turn the FET on too soon - and your ESC shorts the LiPo to ground!
• Hold it on too long, and you apply 'braking' action to the motor.
• Allow also - for the finite time the FET takes to switch on or off.

At the lower power ranges, this can become a difficult juggling act.

So - to amplify the answer to eylau.

If you consistently operate in a low power regime (where timing allowances are the most restricted) then it might be wise to turn off the AFW.
Easier on the ESC and on the Motor.

For higher power regimes, AFW improves efficiency by reducing power losses.

[Iceberg86300]

Originally Posted by SoftShell

Replying to Iceberg.

Yes - ground loops are troublesome.

But in a strict technical sense, they start happening when two devices (or two parts of one larger circuit) have different 'ground' voltages.

Every wire has some resistance, and when current flows through it, a voltage drop occurs. ESC's are big offenders in this regard, since they run quite high motor currents through the battery leads. This return current through the 'black' battery lead can cause the voltage of 'ground' seen inside the ESC to be higher than 0.0 v (relative to the battery). And it jitters, according to the motor current being chopped on-off-on-off all the time.

This jittering 'ground' voltage (inside the ESC) gets added as 'noise' onto the pure clean signal voltage coming from the Receiver's electronics.
It can also inject 'noisy' currents back into your entire system through the 'ground' wire to the Receiver.

Ground loops are a fact of life. Keeping them small and innocuous is the goal.
Having good wires/connectors/solder-joints between the battery and ESC is the first and most important step in reducing ground loops.

Never thought of it like that. I'm just a mechanical engineer with a minor in mechatronics. So I end up dealing more with interface problems and some basic circuit design. I usually go for sensors that amplify their signal before out put so I don't have to be perfect in ground loops and a full ground plane in the board.

Biggest problem I have is sending inductor current from a solenoid turning off into a loop (can't remember the correct term for it) to bleed off the energy.
Regards,

Steve

Sent from Tapatalk using my Inspire 4g through ATT (meaning it's a wonder you can see this!)

[tracernz]

Originally Posted by Iceberg86300

Biggest problem I have is sending inductor current from a solenoid turning off into a loop (can't remember the correct term for it) to bleed off the energy.

That's the same problem as freewheeling in a BLDC motor. Often solved using a freewheeling diode too.

[Iceberg86300]

Originally Posted by tracernz

That's the same problem as freewheeling in a BLDC motor. Often solved using a freewheeling diode too.

Yeah, but there is a term for this which just came to me lol. It's called a flyback circuit.

Regards,

Steve

Sent from Tapatalk using my Inspire 4g through ATT (meaning it's a wonder you can see this!)

[SoftShell]

Originally Posted by Iceberg86300

Biggest problem I have is sending inductor current from a solenoid turning off into a loop (can't remember the correct term for it) to bleed off the energy.

The answer is simple. Use a diode!

This is exactly what the non AFW ESC's do. Except the diode is 'hidden' inside the FET transistors.

[Iceberg86300]

Originally Posted by SoftShell

The answer is simple. Use a diode!

This is exactly what the non AFW ESC's do. Except the diode is 'hidden' inside the FET transistors.

Oh I know! Just couldn't remember the circuit name.

Regards,

Steve

Sent from Tapatalk using my Inspire 4g through ATT (meaning it's a wonder you can see this!)

[Lower!]

Great work!

Question: What are the effects of governor mode vs. running at 90 or 100% throttle with respect to AFW and non-AFW?

I expect that running at 100% throttle is easier on the ESC than governor mode. Where is the break even piont, 95%, 90%, etc.

Thanks,

-Ken

[soko]

Hey guys,

I'm curious about the AFW (active free wheeling) efficiency at ~50% throttle. Does it result in longer flight time compared to a non AFW ESC?

I started a thread about that here.
Some are sayin I get more flight time - some are sayin less

I reckon we need a specialists point of view

thx
Soko