Trevor Grace 1 Posted November 19, 2020 Share Posted November 19, 2020 Just finished setting up he new build but when i turned of the Tx to unplug the battery the motor/prop started rotating.... how and why could this happen. Quote Link to comment Share on other sites More sharing options...
Kim Taylor Posted November 19, 2020 Share Posted November 19, 2020 Sounds like the failsafe settings need to be done. Normally, set the Tx to your desired failsafe settings, then re-bind to the Rx. Check with your radio 'structions in case yours varies. hth Kim Quote Link to comment Share on other sites More sharing options...
Allan Bennett Posted November 19, 2020 Share Posted November 19, 2020 Possibly because failsafe hasn't been set correctly, or it's been deliberately set with low throttle. It therefore activates when it loses Tx signal. Even if your failsafe is set for zero throttle, you should always disconnect the model's battery before turning off the transmitter. Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted November 19, 2020 Share Posted November 19, 2020 Trevor As Allan says unplugging the plane motor battery before turning off the Tx must be considered a safety routine and as important as checking the controls before taking off. Train yourself to do it every time to avoid injury. Quote Link to comment Share on other sites More sharing options...
iflylilplanes Posted November 19, 2020 Share Posted November 19, 2020 Simon is correct, it's a safety routine. I've been flying RC by this rule for 50 years "Transmitter on first and off last", never had a runaway in all that time, seen others have runaways both IC and electric and had a club member carted off to hospital for 57 stitches when the TX was turned off first, electric model chewed his fingers for arms and stomach. The public think we play with toys, we, should know better, our model aircraft are not toys. "Transmitter on first and off last", all the time, failsafe set or not. It's like handling a gun, always handle as if its loaded, that way accidents don't happen. One other safety rule we should all follow is never bench test with a prop on an electric model, if you need to, restrain the model before connecting the battery. Cheers, Dave Quote Link to comment Share on other sites More sharing options...
Trevor Grace 1 Posted November 20, 2020 Author Share Posted November 20, 2020 thanks everyone Quote Link to comment Share on other sites More sharing options...
perttime Posted November 20, 2020 Share Posted November 20, 2020 Posted by iflylilplanes on 19/11/2020 23:37:13: ... "Transmitter on first and off last", all the time, failsafe set or not. It's like handling a gun, always handle as if its loaded, that way accidents don't happen. ... Even better, add more layers of safety: Don't point the loaded model at anything that you don't want chewed up. Quote Link to comment Share on other sites More sharing options...
Former Member Posted November 20, 2020 Share Posted November 20, 2020 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Peter Jenkins Posted November 21, 2020 Share Posted November 21, 2020 Posted by Steve J on 20/11/2020 17:09:51: Posted by Allan Bennett on 19/11/2020 20:18:08: Even if your failsafe is set for zero throttle, you should always disconnect the model's battery before turning off the transmitter. Why? If you have a decent radio and take a bit of time to understand how to use it and setup your models correctly (both of which the OP appears not to have done) then it shouldn't matter if you power up the model before turning on the transmitter and turn off the transmitter before powering down the model. In fact, there is a pretty good case for saying that it is safer to do so. Only if you believe that the software in the ESC is built to safety critical standards. I bet it ain't otherwise we'd not be able to afford it! IC engines that are not running won't suddenly start when the Rx is switched on no matter what software glitch there is. Not so with an electric motor that is connected up before the Tx is switched on. Quote Link to comment Share on other sites More sharing options...
perttime Posted November 21, 2020 Share Posted November 21, 2020 Posted by Steve J on 20/11/2020 17:09:51: Posted by Allan Bennett on 19/11/2020 20:18:08: Even if your failsafe is set for zero throttle, you should always disconnect the model's battery before turning off the transmitter. Why? If you have a decent radio and take a bit of time to understand how to use it and setup your models correctly (both of which the OP appears not to have done) then it shouldn't matter if you power up the model before turning on the transmitter and turn off the transmitter before powering down the model. In fact, there is a pretty good case for saying that it is safer to do so. Because all kinds of accídents tend to result from multiple failures of safety features and safe procedures. It is better to have multiple layers of safety. WHEN one feature or procedure fails, a second or third one can keep you away from ER. Quote Link to comment Share on other sites More sharing options...
Former Member Posted November 21, 2020 Share Posted November 21, 2020 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Chris Walby Posted November 21, 2020 Share Posted November 21, 2020 IMHO the problem is not with the equipment, its with the operator. As the ESC is commanded by a signal to drive the motor then the probability of an internal component failure resulting in the ESC failing is very very small, but not impossible. It is far more probable that either the ESC, RX or TX are not correctly set up correctly and this may be compounded by all of the components being slightly different in how they are set up. Manufacturers put features in place it prevent people doing things they shouldn't (e.g. power on with throttle up), but as they say. Nothing is fool proof to a sufficiently ingenious fool. As you know to design safe control systems, flexibility and accessibility are normally limited to prevent maloperation and we want that flexibility as we use lots of different manufacturers equipment. There are simple safe procedures like prop off that reduce the likelihood of an accident...but people will still get injured even with the prop off. Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted November 21, 2020 Share Posted November 21, 2020 I think one or two of these posts are a little judgemental. Not everyone has the benefit of instructors when they take up the hobby and I would commend the OP for asking for advice. My initial advice to newcomers is always to treat an electric model in the same manner that you would handle an IC model with its engine idling. My pet hate is seeing a hand or arm being passed through the prop arc while handling a model - if you can't connect your battery without doing so, add and use an arming plug or preferably redesign the model to avoid it. Steve has a point and the most common incident that I've witnessed has involved neckstraps catching throttle sticks but a throttle disabling switch on the transmitter will go a long way to avoiding such accidents. I use a mechanically locking switch on all my electric models and program my transmitter so that it will not initialise unless the switch is in the safe position but I appreciate that many beginners won't have this capability. However, it should be regarded as a useful extra layer of protection and never rely on any safety device - always rely on safe handling practice. Transmitter on first - off last has its roots in the pre 2.4 GHz days where stray transmissions were far more likely to cause erroneous operation. I do think that there could be benefit in checking that the correct model has been selected before arming a model though - more so on complex ones with multiple throttle channels, retracts etc. - but it's important to establish a routine right from the beginning. Quote Link to comment Share on other sites More sharing options...
Peter Jenkins Posted November 22, 2020 Share Posted November 22, 2020 Posted by Steve J on 21/11/2020 06:20:25: Posted by Peter Jenkins on 21/11/2020 00:05:29: Posted by Steve J on 20/11/2020 17:09:51: If you have a decent radio and take a bit of time to understand how to use it and setup your models correctly (both of which the OP appears not to have done) then it shouldn't matter if you power up the model before turning on the transmitter and turn off the transmitter before powering down the model. In fact, there is a pretty good case for saying that it is safer to do so. Only if you believe that the software in the ESC is built to safety critical standards. As it happens, I know a thing or two about control and safety systems. What would you say the approximate probabilities of the of the following are: A brushless ESC deciding to spin a motor in the absence of a signal commanding it to do so. A receiver deciding to send a signal to an ESC telling in to spin a motor in the absence of a signal telling it to do so. Maloperation of transmitter leading to a signal being set to the receiver telling it to spin the motor. In my experience, maloperation of the transmitter is dominant, so having the transmitter off while you have your squishy bits near the prop is probably safer than having it on. You shouldn't assume I know nothing about safety crtical software! When arming or disarming electric motors I never rely on the software keeping me safe. That's the accepted way to proceed. Try explaining your ratiknale to the insurance company's lawyer in the event of an accident! Quote Link to comment Share on other sites More sharing options...
Former Member Posted November 22, 2020 Share Posted November 22, 2020 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Former Member Posted November 22, 2020 Share Posted November 22, 2020 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted November 23, 2020 Share Posted November 23, 2020 Steve J, I agree with others that the TX on first off last is the procedure that should always be followed. Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted November 23, 2020 Share Posted November 23, 2020 Tx on first also adds a level of safety in checking the correct model has been selected. I appreciate that not everyone has multiple models and that many systems have model matching protocols ....... As it adds no effort to use Tx on Rx on Rx off Tx off and it MAY reduce risk, why not get into the habit ? GG Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted November 23, 2020 Share Posted November 23, 2020 GG No reason at all not to get into the habit, it is what I have always done. Quote Link to comment Share on other sites More sharing options...
Mike Blandford Posted November 25, 2020 Share Posted November 25, 2020 I have a significant concern regarding multi-protocol modules.All radios have a unique ID used when binding. With the proliferation of multi-protocol modules, which use their own IDs you are no longer certain that your radio ID is unique, a multi-protocol module may be using the same ID. This means a multi-protocol module user could "shoot down" your aircraft (and/or you could "shoot down" their aircraft)! The ID used in the multi-protocol module does depend on which protocol it is using. There is a danger if a MPM and your radio share the same ID. If both transmitters are powered on, then when you power on your receiver, you don't know which Tx it will "lock on to", it could be either. If you have an electric powered model, and "the other" Tx is sending something other than low throttle on YOUR throttle channel, then your model's motor would start unexpectedly. If you power your Rx on before your Tx, then, in the above scenario, it would lock on to the other Tx, at least if you power your Tx on first, there is a (50%?) chance your Rx will lock on to your Tx. Mike Quote Link to comment Share on other sites More sharing options...
Former Member Posted November 25, 2020 Share Posted November 25, 2020 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Former Member Posted November 25, 2020 Share Posted November 25, 2020 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Robert Welford Posted November 25, 2020 Share Posted November 25, 2020 Posted by Steve J on 22/11/2020 21:59:31: Please explain why (1) is safer than (2) assuming that the failsafe was set correctly. You've answered your own question: in the case the fail-safe is incorrectly set and goes to full power on switch-on. I 'm aware of a situation where the Rx had lost the fail-safe settings for no reason. I too am a member of the "Tx on Rx on and Rx off Tx off " brigade. Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted November 25, 2020 Share Posted November 25, 2020 Isn't this discussion missing the basic point - any model with its flight battery connected is potentially hazardous. There can be no exceptions to this - neither transmitter on or off first is going to be 100% safe and we can argue the merits of either principle until the cows come home to graze on the patch. You may say that all your models' throttles operate in the same direction but this won't necessarily protect you when you switch on with an IC model selected that goes the opposite way to your ESCs or are helping a beginner. The only real failsafe is in your care and forethought - every electronic or physical precaution is simply an additional layer to protect against failure to handle the model safely. What you must do is discipline yourself that while you take any additional precautions, you must handle the model as if you believe it can go to full throttle at any time - whether connecting the battery, carrying it to/from the strip or approaching it to retrieve it. For example, I always either taxi past myself or turn the model nose away before removing it from the flying area. If you need to go out onto the runway/field to retrieve a model, always approach it from behind whether you are in control of your transmitter or not. Quote Link to comment Share on other sites More sharing options...
Lima Hotel Foxtrot Posted November 26, 2020 Share Posted November 26, 2020 What does the BMFA handbook say? Quote Link to comment Share on other sites More sharing options...
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