---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 05/21/17: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:48 AM - Flaps system tripping the circuit breaker (Carlos Trigo) 2. 04:16 AM - Re: Flaps system tripping the circuit breaker (Charles Kuss) 3. 04:46 AM - Re: Flaps system tripping the circuit breaker (Charlie England) 4. 04:46 AM - Re: Flaps system tripping the circuit breaker (Rob Turk) 5. 07:16 AM - Re: IVO Prop current limiter (merlewagner2) 6. 10:43 AM - Re: Flaps system tripping the circuit breaker (Robert L. Nuckolls, III) 7. 10:51 AM - Re: Flaps system tripping the circuit breaker (Robert L. Nuckolls, III) 8. 08:40 PM - Re: Flaps system tripping the circuit breaker (Bill Watson) ________________________________ Message 1 _____________________________________ Time: 02:48:59 AM PST US From: "Carlos Trigo" Subject: AeroElectric-List: Flaps system tripping the circuit breaker One of my aviator friends called me to help him solving a problem in his RV-7 flaps system. He told me that occasionally, when he retracts the flaps, the correspondent Circuit Breaker trips. But not always, so he resets the CB and the flaps keep working normally. I asked him to measure the current during the flaps movement, and he measured 1 to 2 A when extending and when retracting, but he noticed that after full retraction the current went to 7 A. That explains why the CB (5A) trips. I think most of you know that the flaps system in an RV airplane is powered by an electric motor with 2 wires, which make the flaps work in both senses, just with reversing the electrons movement on those 2 wires. You also probably know that the motor doesn't stop at both ends if you don't release the switch, so the motor keeps turning even when the flaps reach full extension and full retraction. Now the question: which can be the reason for the current peak that the motor is reaching at full retraction? Any help welcome Thanks Carlos ________________________________ Message 2 _____________________________________ Time: 04:16:11 AM PST US From: Charles Kuss Subject: Re: AeroElectric-List: Flaps system tripping the circuit breaker Due to the mostly vertical orientation of the motor, the grease in the bearings will sometime migrate down onto the commutator/brush area of the armature. This is a common issue. It requires removal and disassembly of the motor to clean the grease off the armature and re-grease the bearings. Charlie -------------------------------------------- On Sun, 5/21/17, Carlos Trigo wrote: Subject: AeroElectric-List: Flaps system tripping the circuit breaker To: aeroelectric-list@matronics.com Date: Sunday, May 21, 2017, 5:47 AM One of my aviator friends called me to help him solving a problem in his RV-7 flaps system.He told me that occasionally, when he retracts the flaps, the correspondent Circuit Breaker trips. But not always, so he resets the CB and the flaps keep working normally. I asked him to measure the current during the flaps movement, and he measured 1 to 2 A when extending and when retracting, but he noticed that after full retraction the current went to 7 A.That explains why the CB (5A) trips. I think most of you know that the flaps system in an RV airplane is powered by an electric motor with 2 wires, which make the flaps work in both senses, just with reversing the electrons movement on those 2 wires. You also probably know that the motor doesnt stop at both ends if you dont release the switch, so the motor keeps turning even when the flaps reach full extension and full retraction. Now the question: which can be the reason for the current peak that the motor is reaching at full retraction? Any help welcomeThanksCarlos ________________________________ Message 3 _____________________________________ Time: 04:46:16 AM PST US From: Charlie England Subject: Re: AeroElectric-List: Flaps system tripping the circuit breaker On Sun, May 21, 2017 at 4:47 AM, Carlos Trigo wrote : > One of my aviator friends called me to help him solving a problem in his > RV-7 flaps system. > > He told me that occasionally, when he retracts the flaps, the > correspondent Circuit Breaker trips. But not always, so he resets the CB > and the flaps keep working normally. > > > I asked him to measure the current during the flaps movement, and he > measured 1 to 2 A when extending and when retracting, but he noticed that > after full retraction the current went to 7 A. > > That explains why the CB (5A) trips. > > > I think most of you know that the flaps system in an RV airplane is > powered by an electric motor with 2 wires, which make the flaps work in > both senses, just with reversing the electrons movement on those 2 wires. > You also probably know that the motor doesn=99t stop at both ends i f you > don=99t release the switch, so the motor keeps turning even when th e flaps > reach full extension and full retraction. > > > Now the question: which can be the reason for the current peak that the > motor is reaching at full retraction? > > > Any help welcome > > Thanks > > Carlos > > My 1st guess is that the flap linkage is slightly out of adjustment. If the flaps hit their stops before the motor reaches full retraction, it would still trying to pull instead of free-wheeling. My 2nd guess (after looking at the 10A flaps breaker in my RV-4, and looking at the specs for the motor that's inside the actuator) is that he's using the wrong breaker. Corollary to my 2nd guess is that he's holding the up button too long. :-) Charlie ________________________________ Message 4 _____________________________________ Time: 04:46:24 AM PST US Subject: Re: AeroElectric-List: Flaps system tripping the circuit breaker From: Rob Turk Is there a functional limit switch in this system? If you hit the physical end of travel for the flap system and there's no limit switch, the motor will keep on pulling at maximum power. Current draw will be a lot higher and if it wasn't for the CB, you'd probably burn up the motor. On 5/21/2017 11:47 AM, Carlos Trigo wrote: > > One of my aviator friends called me to help him solving a problem in > his RV-7 flaps system. > > He told me that occasionally, when he retracts the flaps, the > correspondent Circuit Breaker trips. But not always, so he resets the > CB and the flaps keep working normally. > > I asked him to measure the current during the flaps movement, and he > measured 1 to 2 A when extending and when retracting, but he noticed > that after full retraction the current went to 7 A. > > That explains why the CB (5A) trips. > > I think most of you know that the flaps system in an RV airplane is > powered by an electric motor with 2 wires, which make the flaps work > in both senses, just with reversing the electrons movement on those 2 > wires. You also probably know that the motor doesnt stop at both ends > if you dont release the switch, so the motor keeps turning even when > the flaps reach full extension and full retraction. > > Now the question: which can be the reason for the current peak that > the motor is reaching at full retraction? > > Any help welcome > > Thanks > > Carlos > ________________________________ Message 5 _____________________________________ Time: 07:16:40 AM PST US Subject: AeroElectric-List: Re: IVO Prop current limiter From: "merlewagner2" Bob, When you get the new circuit up I would be very interested in purchasing. Have the Ivo mag prop which will be interfacing with a Viking Turbo 170HP. Should be interesting to see the performance. Merle -------- KC1DNJ General Radiotelephone Commercial SEL A&P Building scale P51 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=469481#469481 ________________________________ Message 6 _____________________________________ Time: 10:43:34 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Flaps system tripping the circuit breaker At 06:14 AM 5/21/2017, you wrote: > >Due to the mostly vertical orientation of the motor, the grease in >the bearings will sometime migrate down onto the commutator/brush >area of the armature. This is a common issue. It requires removal >and disassembly of the motor to clean the grease off the armature >and re-grease the bearings. Contamination of the commutator can indeed manifest in mis-behavior of the motor but not over-current. Are these ball bearings? If so, they are most likely a metric standard. You might fix the problem with factory lubricated, sealed bearings. Bob . . . ________________________________ Message 7 _____________________________________ Time: 10:51:45 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Flaps system tripping the circuit breaker > > >My 1st guess is that the flap linkage is >slightly out of adjustment. If the flaps hit >their stops before the motor reaches full >retraction, it would still trying to pull instead of free-wheeling. > >My 2nd guess (after looking at the 10A flaps >breaker in my RV-4, and looking at the specs for >the motor that's inside the actuator) is that he's using the wrong breaker. > >Corollary to my 2nd guess is that he's holding the up button too long. :-) =C2 > >Charlie Agreed. The spec sheet shows a motor resistance of 0.83 ohms. Add another few tenths of an ohm for wiring and we still have an inrush current potential on the order of 10 amps. So yes, the 5A breaker MIGHT be marginal . . . but I would expect it to operate on both extend or retract cycles . . . especially extend when the motor is pushing flaps into the slip-stream. So your first guess sounds like the right one . . . the flaps are hitting mechanical stops and stalling the motor . . . Well adjusted limit switches would be a sanitary solution. Bob . . . ________________________________ Message 8 _____________________________________ Time: 08:40:07 PM PST US Subject: Re: AeroElectric-List: Flaps system tripping the circuit breaker From: Bill Watson Just an aside but this issue helps justify the decision to make the only CBs in my RV for the AP, the voltage regulator and flaps (none have tripped to date however). Everything else is protected by fuses that I don't intend to 'reset' in the air Bill "keeping the pilot as proficient as the plane is the perpetual challenge" Watson --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.