Motor shut down

[coolice]

Hi Ian, Sorry to be a PITA but surely a cold dry atmosphere would be worse for generating static as a moist or damp environment would assist in allowing any static electric charge to find an easier route to earth. Static electricity must be more of a problem in the dryer states in the USA and that is probably where the problem was identified. Pity he is not using telemetry as that would give a clue as to what is happening. We did find a non soldered ESC motor connector on an Align kit at our club recently which only made an appearance during the first check flight and that caused the motor to stop, so it might be a good idea to strip off the sleeving off the motor wires and check all of the motor power connectors.

Barry

Hey Barry.

Yep you're dead right, it's more of a problem in drier conditions. Just been going over some topics in Helifreak which has refreshed that information.
Should have remembered from the old 3GX conversation's where people were having static problems.

Just come across a thread on HF on the 470L and static, not many got involved but one thing that was mentioned was the metal belt pulley at the front of the boom one guy found to not help.

So we can almost rule out static, as it's not really been dry. But did the moist air help channel it to where it shouldn't be if some static did build up?

Ian Contessa

[feathering]

What percentage of throttle are you running?

Ian, I am Flying Taranis with an FrSky X4R-SB receiver. As for the curves, I run a flat curve ungoverned at around 80%. (I noticed that from 85% to 100% the RPM doesn't seem to change so perhaps I am closer to 100% than what my TX seems to suggest.)

[coolice]

Ian, I am Flying Taranis with an FrSky X4R-SB receiver. As for the curves, I run a flat curve ungoverned at around 80%. (I noticed that from 85% to 100% the RPM doesn't seem to change so perhaps I am closer to 100% than what my TX seems to suggest.)

Evening mate.

Ah cool, stops another idea thinking in case you were running a low throttle percentage for extended periods of time. But then you wouldn't be to obtain a decent head speed.

Keep us posted on what you figure out over your next flights.

Ian Contessa

[woodsta888]

To OP,

Are you using 1 or 2 sats powered from your FBL unit or a full Rx?

I had this issue a couple of years ago. In the end I swapped to a full Rx and 1 sat instead of 2x sats from the FBL. I recall that some FBL's draw alot of power (some upto 20A under full servo loads) and as some RX protocols arent actually licenced to FBL manufacturers or guaranteed via the FBL so if you have tiring Lipos, a BEC that won't supply a high amperage and HV servos then the first thing to drop can be the satellites powered by the FBL. As previously mentioned DSMX is very quick to reboot in a brownout causing only momentary loss of power if you have your failsafe set up correctly.

I don't use a BEC and opt for a 2s LIfE PO4 battery (not such an easy option on smaller heli's) to provide seprate power for my electronics. Both the full Rx and the FBl having it's own supply. Plus with the LiFE battery's hold a better voltage (albeit not 8.4v for HV batteries) throughout it's discharge. Spektrum sats require a minimum of 5.5v to operate.

But I do remember having these motor shutdowns momentarily on my 800 in the hover with full control of the control surfaces. Never had it since changing to full RX.

[Grumpy]

He's using FrSky, so normal Rx, no sats.

[feathering]

A few flights over the weekend suggest that I am having range issues with the 470l. Approximately 2 min into my 3rd flight (following 2 short calm flights) I started getting low RSSI warnings from my Taranis. A range test confirmed that transmission was very poor. This is the first time ever I receive such warnings. What I find surprising is that when I experienced the shutdowns last time I did not get any warning.

Is it common that receivers weaken over time? I was under the impressions that receivers either work or not rather than just deteriorating over time. Perhaps static is adding to all this.

I will be getting another receiver at some point and will also apply some silicone to the belt and see if that solves the issue.

[brin]

Hi Fernando.I have some anti static spray and can also check to see where most of the static is coming from if any.What receiver do you need as i am sure someone at the club could lend you one just to try.

A few flights over the weekend suggest that I am having range issues with the 470l. Approximately 2 min into my 3rd flight (following 2 short calm flights) I started getting low RSSI warnings from my Taranis. A range test confirmed that transmission was very poor. This is the first time ever I receive such warnings. What I find surprising is that when I experienced the shutdowns last time I did not get any warning.

Is it common that receivers weaken over time? I was under the impressions that receivers either work or not rather than just deteriorating over time. Perhaps static is adding to all this.

I will be getting another receiver at some point and will also apply some silicone to the belt and see if that solves the issue.

[trillian]

Is it common that receivers weaken over time? I was under the impressions that receivers either work or not rather than just deteriorating over time. Perhaps static is adding to all this.

I will be getting another receiver at some point and will also apply some silicone to the belt and see if that solves the issue.

Yeah could be static. I had a static problem a long time ago with a Trex 450SE and cured it with a bit of wire to earth the boom to the motor mount. Receivers generally just work or they don't but it's possible to have a solder joint somewhere get loose over time due to vibrations or changes in temperature etc.

When I built my gasser and was doing the first trim / tuning flights I once had a flashing light on the FBL unit (Spartan VX1) indicating a signal loss. I had seen nothing at all in flight though, not the slightest glitch. Looking at the logs there were multiple points where the signal dropped out. So I went back to basics on placement of the sats making sure they were far enough from any carbon or metal etc. and I replaced the sats with new ones. After that the logs were very clean, little to no dropouts. But having said that - in all the years of flying Spektrum and having sometimes become very casual with the sats, they always worked anyway.

[Grumpy]

Static would just knock the Rx out for a momemt. It wouldnt explain a sustained weak signal. Where are your antenna placed? If not well placed the antenna may be getting shielded by the frame of the heli.

[feathering]

Thank you for the replies. Wil keep your comments in mind.

The antennas are possibly not well placed: both antennas are parallel (so much for diversity) and attached to the boom with a zip tie...this is what I did. So possibly a good time to rethink things. But again, I have had this 470l for about 8 months and never had any signal strength warning until now.

Thank you Brian. I will contact you offline about the possibility of looking into this at the club together.

[coolice]

Hey buddy.

Could it be something as simple as aerial fatigue?
Might be broken somewhere and in flight making intermittent contact, hence the problem showing sometimes.

Just an idea.

Ian Contessa

[feathering]

Reporting back.

Managed to get a couple of flights over the weekend with no issues. May be too early to say but looks promising. Here is what I have done so far:

1) Replaced the frsky x4r-sb receiver with a new one. Not sure whether the receiver was the cause of my motor shutdown issues or else whether it was somehow damaged along the way but, as mentioned in an earlier post, I could no longer fly with that receiver. Following the shutdown events I was getting constant RSSI warnings. No warnings with the new receiver.

2) Applied silicone oil to the belt. I used an AC voltage detector prior to applying the oil and the device was sensing voltage all the way from the boom clamp to the tail case. In fact for most of the boom length the device was reporting 100% on its detection range (not sure what voltage 100% represents but it was a bit scary nevertheless). After applying the silicone the detector went quiet. What a difference! I used pure silicone oil for treadmills, e.g. this one.

3) Improved RX antenna placement. Using two zip ties around the boom and orienting the excess ties nearly 180 degrees from each other I attached each antennas to each of the excess ties. This separates the antennas from the boom coming out at an angle. I may get something like this if I want a cleaner set up.

Thank you all for your help on this. The discussions were very interesting and have given me enough ideas to try a few things.