Align 600MX motor shutting down

[atomiccomp]

I've run the exact same combo without any issue. the Align motors run very hot at the best of times, so unless it's literally hot enough to brand you then it's normal. Personally I now always set the PWM to the highest value available (24kHz on the Castle) and use default timing, but I've ran lots of different settings and never experienced any cut outs. Set low voltage cut to 'Slow down' (though voltage looks fine in the log).

i think you can rule out over-amping the ESC if you were only hovering, and the log file supports that.

I think a motor fault unlikely. Brushless motors are very simple things and generally they either work or they don't. If it's an intermittant problem then most times the problem is elsewhere. As already noted check the connections and also check that a sharp edge hasn't cut through the insulation on the motor wires causing an intermittent short.

Do you still have control of the servos when the motor cuts?.. That would be the first thing to check because it could be a brownout (if so the servos will freeze momentarily when the motor cuts). How are you powering the FBL / servos?

I second that, I had the same issue and it was the FBL unit going into failsafe because of a dodgy SBUS connection. You could be looking in the wrong place for the issue, Just as I did initially. Worth a double check especially if your FBL has logging.

[atomiccomp]

It works now.

From the looks of both logs you have 3 or 4 amp and motor % drops. If I read them right it looks like something has told the ESC to cut power. I have some castle esc's and when they go into protect mode ( detecting low voltage or pulling to many amps they stay at low RPM till you cycle your throttle) . Might be a pointer.

[Granpappy]

I've run the exact same combo without any issue. the Align motors run very hot at the best of times, so unless it's literally hot enough to brand you then it's normal. Personally I now always set the PWM to the highest value available (24kHz on the Castle) and use default timing, but I've ran lots of different settings and never experienced any cut outs. Set low voltage cut to 'Slow down' (though voltage looks fine in the log).

i think you can rule out over-amping the ESC if you were only hovering, and the log file supports that.

I think a motor fault unlikely. Brushless motors are very simple things and generally they either work or they don't. If it's an intermittant problem then most times the problem is elsewhere. As already noted check the connections and also check that a sharp edge hasn't cut through the insulation on the motor wires causing an intermittent short.

Do you still have control of the servos when the motor cuts?.. That would be the first thing to check because it could be a brownout (if so the servos will freeze momentarily when the motor cuts). How are you powering the FBL / servos?

I still have full servo control when the motor cuts (thank goodness). The receiver power supply is 2S 3300mah 20C lipo directly into the FBL. The FBL routes power to the receiver through a single SBUS connection. The main power supply is 2 X 6s 3300mah 50C. I calibrated the throttle by setting 50% on both endpoints, and at full throttle moving endpoint up till esc beeps and then the same for zero throttle.

I will change the receiver battery to a new one and change the esc settings as previously mentioned and try it again. I cant find any insulation cuts on the motor leads. Thanks for the help.

[Granpappy]

From the looks of both logs you have 3 or 4 amp and motor % drops. If I read them right it looks like something has told the ESC to cut power. I have some castle esc's and when they go into protect mode ( detecting low voltage or pulling to many amps they stay at low RPM till you cycle your throttle) . Might be a pointer.

The motor picked up again each time without cycling the throttle. What actually happened is I was hovering at about 5 metres checking for waggles, nods etc. and checking rudder control and stops, when the motor cut. The heli descended and I put in more collective to slow the descent rate, the motor picked up again and I was back in the hover. Luckily the rotor speed decay wasn't too rapid. This happened 3 times before I put the heli on the ground and checked temps. I let everything cool for a couple of minutes and then went back into the hover. The motor cut again in less than a minute so I got back on the ground and stopped flying.

FBL doesn't have logging.

I still believe it's a temperature related issue because of the timing when these events occurred. The esc didn't get unduly hot, (50 deg C) according to the log, but the motor got hot.

[Granpappy]

This is a close up of one of the events. The rest are the same. It shows the ripple voltage dropping a couple of seconds before the motor cut out. I don't know the significance of this or whether it has any bearing on the issue.

[Grumpy]

The trace clearly shows that the current drops to zero, so for some reason the ESC is briefly cutting all power to the motor. It cant be caused by the motor overheating because the ESC has no way of 'knowing' if the motor is hot or cold, and the motor being hot in itself wouldn't cause all current to stop flowing momentarily. Like I mentioned previously, those Align 600MX motors normally run very hot.

If the wiring all checks out and if you have normal control then I'd be suspecting the ESC. Do you have another ESC that you could try to narrow down the issue?

Slightly odd that the last time I saw something similar to this was a guy at the field where i fly with a Trex 500 Pro who was also using the BD 3SX FBL controller. Symptoms were exactly the same, motor died briefly then spooled back up, full control throughout. In that case we tried a different ESC and he still had the problem. I cant think of how it could be the 3SX causing the issue, probably just coincidence, but odd nonetheless. Never did get to the bottom of that one, he sold the heli.

[Granpappy]

The only other esc big enough is on my 500. I could swap them out but we shall see what todays events bring first. Strangely the 500 has a BD 3SX controller but I've had no problems with motor control. The unit just passes the throttle signal through. If I wasn't using SBUS then the ESC throttle control will be plugged directly into the receiver.

I did find the ripple voltage on the graph above quite odd. It did significantly drop just before the motor cut out. I think ripple voltage has to do with how the capacitors are coping with the power draw from the main batteries. If the batteries cant supply enough current then the ripple voltage will spike. The batteries however are 50C so I cant see that as a problem. I've set the current limit on the ESC to 'disabled' which should apparently prevent any ripple current fluctuation from causing a shut down.

Anyway, I'm off to the field again. Wish me luck.

[kenny d]

I've got a spare cc ice 100 lying here , I'd be happy to send it to you to try it if you wish , there's nothing worse than intermittent problems , hopefully it will be ok today , regards Kenny d

[GIXERMAN]

I've got a spare cc ice 100 lying here , I'd be happy to send it to you to try it if you wish , there's nothing worse than intermittent problems , hopefully it will be ok today , regards Kenny d

won't be no good, as only can't take 8S

[Grumpy]

Good luck at the field... But if the problem persists I've got a Hobbyking Rotorstar 120A HV still in the box (same ESC as the YEP / YGE clone).. if you want to borrow it just say, needs connectors soldered.

I agree that it's hard to see why the 3SX could be the cause. As you say, throttle is just a pass-through, or it should be.

[Granpappy]

Well humbug. Same problem even with all the changes. However the motor now runs a lot cooler since setting it to 12Khz. Another odd thing is head speed is about 1400 rpm. Really slow. It is set at 65% on the transmitter at 5 deg pitch but it's definitely not making that. The throttle input should show a signal between 1ms and 2 ms between min and max and therefore should be at 1.65ms in the hover. It's a lot less then that on the graph. So I've no idea.

I'll send the log files to Castle Creation tech support and see if they can throw some light on it. Meanwhile I'll fit my Align BLE70 esc in and see if that works okay.

[Granpappy]

I've got a spare cc ice 100 lying here , I'd be happy to send it to you to try it if you wish , there's nothing worse than intermittent problems , hopefully it will be ok today , regards Kenny d

won't be no good, as only can't take 8S

Good luck at the field... But if the problem persists I've got a Hobbyking Rotorstar 120A HV still in the box (same ESC as the YEP / YGE clone).. if you want to borrow it just say, needs connectors soldered.

I agree that it's hard to see why the 3SX could be the cause. As you say, throttle is just a pass-through, or it should be.

Many thanks guys. I will fit the Align ESC from my 500 and see whether that works okay.

[trillian]

Many thanks guys. I will fit the Align ESC from my 500 and see whether that works okay.

At the risk of pointing out the obvious, the ESC from the 500 will only handle 6s.

I'll speak to the guy that is doing a rewind for me and see if he can post you the spare 600mx that he is not rewinding (I sent him two in case one is more favourable for rewinding). Then you could easily eliminate one of the three variables from the equation (and if it works you're done, no need to fiddle any further).

[Granpappy]

At the risk of pointing out the obvious, the ESC from the 500 will only handle 6s.

I'll speak to the guy that is doing a rewind for me and see if he can post you the spare 600mx that he is not rewinding (I sent him two in case one is more favourable for rewinding). Then you could easily eliminate one of the three variables from the equation (and if it works you're done, no need to fiddle any further).

Yes. School boy error. I hadn't thought of that. I'm too used to flying 6s.

I do appreciate the offer Sheryl but please don't ask your friend to send another motor. I think Steve has convinced me that it is not a motor fault and I'm sorry that I ever doubted the motor. Thank you again.

[GIXERMAN]

im assuming your running this motor on 12 cells, 1400 rpm is like scale. what gearing are you running and why not use the governor rather than curves ?