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Re: "Coil suppression can reduce relay life"
David A Froble
Grow some thicker skin. I found Ben's explanation (not lecture) quite educational.
On 5/13/2019 8:59 AM, Bruce Hughes ezcopilot@... [canard-aviators] wrote: Ben, why are you lecturing me?allow the current associated the the flyback voltage to flow back to the switch. The breakdown of the Zener diode is a no destructive process. I hope this is clear enough to understand.t 1:01 PM Bill Allen billallensworld@... [canard-aviators] <canard-aviators@...> wrote: Having had master contractors fail on me in certified aircraft, I am seriously contemplating replacing an electromechanical (traditional master solenoid) with a simple mechanical one, which, as a bonus, doesn’t consume power ( about 1.5a)Flaming River do a range of these devices;http://www.flamingriver.com/index.php/products/c0015/s0001/FR1013 and, for Education and Recreation, could provide a simpler solution in an experimental aircraft.Bill AllenOn Sat, 11 May 2019 at 18:40, Mike Satchell mike.satch@... [canard-aviators] <canard-aviators@...> wrote: Jack, The starter solenoid is my highest concern regarding this topic. It's not uncommon for them to fail and sometimes, it is a catastrophic event. An increased breaking force (faster drop out) should decrease the likelihood of welded contacts. Regards,Mike SatchellOn 5/11/2019 10:42 AM, jack711cz eznose lift@... [canard-aviators] wrote: MIke:Your missing the point here. The point is relay reliability, not drop out time.RegardsJack WilhelmsonOn Sat, May 11, 2019 at 10:39 AM Mike Satchell mike.satch@... [canard-aviators] <canard-aviators@...> wrote: Same resistive load, same type of relay, same number of cycles.Long versus short decay rates.I posted the original note to point out something I thought was unusual and noteworthy since most of us are familiar with the benefits of suppression diodes, but weren't aware of the unintended consequences. Regards,Mike SatchellOn 5/11/2019 8:59 AM, jack711cz eznoselift@... [canard-aviators] wrote: This data shows that the diode slows the coil drop out but there is no data about the failure rate or the number of actuations before failure of the relay. This kind of data is usually in the 30,000 to 50,000 (same as UL testing of switches).BS is often supported by non relevant data.RegardsJack WilhelmsonOn Sat, May 11, 20 19 at 9:19 AM Mike Satchell mike.satch@... [canard-aviators] <canard-aviators@yahoogroups...com> wrote: Apparently there is more fact than opinion as it is a measurable phenomena.http://www.crydom..com/en/tech/newsletters/solid%20statements%20-%20coil%20suppression%20&%20dc%20output%20ssrs.pdfThis from Wikipediahttps://en.wikipedia.org/wiki/Flyback_diode "When the inductive load is a relay, the flyback diode can noticeably delay the release of the relay by keeping the coil current flowing longer. "On 5/11/2019 8:08 AM, jack711cz eznoselift@... [canard-aviators] wrote: This "so called technical" articular is nothing more than one engineers opinion. No data on testing to actually show how much a diode across a relay coil, to stop negative voltage kick back, shortens the relay life. I have been using relays with diode kickback protection for forty years. They become very important when the relay coil driver circuits are solid state electronics. I also have my own opinion and many years of experience and it does not agree.RegardsJack WilhelmsonOn Fri, May 10, 2019 at 8:21 AM skyeyecorp@... [canard-aviators] <canard-aviators@yahoogroups..com> wrote: Very interesting little article Mike. A worthwhile refinement to established procedure to keep in mind for the next time I wire a master/starter contactor.--JoseOn Thu, May 9, 2019, at 9:40 PM, Mike Satchell mike.satch@... [canard-aviators] wrote: Here is an interesting application note suggesting the use of zener diodes in series with the suppression diodes particularly when solid state switches are used. Maybe the lone diodes across the master and starter relays coils are great for EMF suppression but less than optimal for breaking the contacts open. ...https://www.te.com/commerce/DocumentDelivery/DDEController?Action=srchrtrv&DocNm=13C3264_AppNote&DocType=CS&DocLang=EN-- Sent from Gmail Mobile -- David Froble Tel: 724-529-0450 Dave Froble Enterprises, Inc. E-Mail: davef@... DFE Ultralights, Inc. 170 Grimplin Road Vanderbilt, PA 15486
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Re: "Coil suppression can reduce relay life"
Bruce Hughes
Ben, why are you lecturing me? I said nothing about zener diodes; I just said that I use B & C electronic parts. Apparently you did not read their catalog. I knew what Zener diodes do and used one in HAM equipment in 1958. I need help on a totally different part of the Longeze. NOW I am afraid to ask; I will get lectured again. Geeez. Bruce
----- Original Message ----- From: Ben Bennett benbenne@... [canard-aviators] To: Bruce Hughes ezcopilot@... [canard-aviators] Sent: Sun, 12 May 2019 23:08:34 -0400 (EDT) Subject: Re: [c-a] "Coil suppression can reduce relay life" A relay is nothing but a coil with a iron contacts. When the relay is energized it creates a magnetic field which closes the contacts. When the relay is turned off creating an open circuit, the energy field built up by the coil has to dissipate somewhere. In the open circuit it creates a flyback voltage that can be large enough to arc across the contacts. This is what causes the arcing across the contacts. With a Zener diode in place, when the flyback voltage reaches 24v the Zener diode breaks down allowing the energy from the coil to be dissipated before it will arc across the contacts, saving the contacts. A Zener diode is a device which blocks current from flowing in the reverse direction until it reaches its critical voltage, in this case 24v. Once it breaks down it allows the current to flow to ground thru a resistor which slow the current flow to ground. The other normal diode allow the current to flow in the normal direction when the power switch. is on but does not allow the current associated the the flyback voltage to flow back to the switch. The breakdown of the Zener diode is a no destructive process. I hope this is clear enough to understand. Ben Bennett On Sunday, May 12, 2019 10:13:24 AM CDT, Bruce Hughes ezcopilot@... [canard-aviators] wrote: I suggest you Look in the B & C catalog for the S811-1 and S701-1 This is NOT a recommendation; just telling you how my Longeze is powered. I also have B & C starter, alternator, linear controller, 20 position fuse holder, fuses (that indicate when blown so easy to find), and a grounding block. I had a lot of electrical system trouble before I started buying from B & C. Remember this is NOT a recommendation. Bruce Hughes Bruce Hughes ----- Original Message ----- From: jack711cz eznoselift@... [canard-aviators] To: Canard Aviators Sent: Sat, 11 May 2019 15:55:08 -0400 (EDT) Subject: Re: [c-a] "Coil suppression can reduce relay life" Master solenoid failure is very common when using the traditional circuit that feeds the starter solenoid (200amp intermittent ratting) current through the master solenoid (30 amp continuous rattng). This subject has been discussed on the Cozy forum. Regards Jack Wilhelmson On Sat, May 11, 2019 at 1:01 PM Bill Allen billallensworld@... [canard-aviators] <canard-aviators@...> wrote:
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Re: "Coil suppression can reduce relay life"
Ben Bennett
A relay is nothing but a coil with a iron contacts. When the relay is energized it creates a magnetic field which closes the contacts. When the relay is turned off creating an open circuit, the energy field built up by the coil has to dissipate somewhere. In the open circuit it creates a flyback voltage that can be large enough to arc across the contacts. This is what causes the arcing across the contacts. With a Zener diode in place, when the flyback voltage reaches 24v the Zener diode breaks down allowing the energy from the coil to be dissipated before it will arc across the contacts, saving the contacts. A Zener diode is a device which blocks current from flowing in the reverse direction until it reaches its critical voltage, in this case 24v. Once it breaks down it allows the current to flow to ground thru a resistor which slow the current flow to ground. The other normal diode allow the current to flow in the normal direction when the power switch. is on but does not allow the current associated the the flyback voltage to flow back to the switch. The breakdown of the Zener diode is a no destructive process. I hope this is clear enough to understand. Ben Bennett
On Sunday, May 12, 2019 10:13:24 AM CDT, Bruce Hughes ezcopilot@... [canard-aviators] wrote:
I suggest you Look in the B & C catalog for the S811-1 and S701-1 This is NOT a recommendation; just telling you how my Longeze is powered. I also have B & C starter, alternator, linear controller, 20 position fuse holder, fuses (that indicate when blown so easy to find), and a grounding block. I had a lot of electrical system trouble before I started buying from B & C. Remember this is NOT a recommendation. Bruce Hughes Bruce Hughes ----- Original Message ----- From: jack711cz eznoselift@... [canard-aviators] To: Canard Aviators Sent: Sat, 11 May 2019 15:55:08 -0400 (EDT) Subject: Re: [c-a] "Coil suppression can reduce relay life" Master solenoid failure is very common when using the traditional circuit that feeds the starter solenoid (200amp intermittent ratting) current through the master solenoid (30 amp continuous rattng). This subject has been discussed on the Cozy forum. Regards Jack Wilhelmson On Sat, May 11, 2019 at 1:01 PM Bill Allen billallensworld@... [canard-aviators] <canard-aviators@...> wrote:
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(No subject)
David A Froble
On 5/12/2019 1:47 PM, Ken Swain ken4zz@... [canard-aviators] wrote:
Something like this?Well, yeah, sort of .... As I read about the device, it's for a single airspeed, and perhaps for a single purpose. I'd prefer having the option of multiple controls, possibly for multiple airspeeds. Not sure what all might be involved. Current topic is landing brake, but other things could be applicable. Auto up for landing brake above a certain airspeed for another. It appears that builders have implemented specific solutions for specific problems. Enough of those can become complex. At some point, simplicity might be better achieved with a system that handles all the issues. On 5/12/2019 9:37 AM, Dave Froble davef@... [canard-aviators]-- David Froble Tel: 724-529-0450 Dave Froble Enterprises, Inc. E-Mail: davef@... DFE Ultralights, Inc. 170 Grimplin Road Vanderbilt, PA 15486
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(No subject)
Something like this? http://www.aircraftextras.com/RelaySpeedCont1.htm Fancy smartphone level electronics not needed. Ken
On 5/12/2019 9:37 AM, Dave Froble
davef@... [canard-aviators] wrote:
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Re: "Coil suppression can reduce relay life"
Bruce Hughes
I suggest you Look in the B & C catalog for the S811-1 and S701-1 This is NOT a recommendation; just telling you how my Longeze is powered. I also have B & C starter, alternator, linear controller, 20 position fuse holder, fuses (that indicate when blown so easy to find), and a grounding block. I had a lot of electrical system trouble before I started buying from B & C. Remember this is NOT a recommendation. Bruce Hughes Bruce Hughes
----- Original Message ----- From: jack711cz eznoselift@... [canard-aviators] To: Canard Aviators <canard-aviators@...> Sent: Sat, 11 May 2019 15:55:08 -0400 (EDT) Subject: Re: [c-a] "Coil suppression can reduce relay life" Master solenoid failure is very common when using the traditional circuit that feeds the starter solenoid (200amp intermittent ratting) current through the master solenoid (30 amp continuous rattng). This subject has been discussed on the Cozy forum. Regards Jack Wilhelmson On Sat, May 11, 2019 at 1:01 PM Bill Allen billallensworld@... [canard-aviators] <canard-aviators@...> wrote:
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(No subject)
David A Froble
On 5/12/2019 10:14 AM, jschuber@... [canard-aviators] wrote:
While the landing brake is strong, it does have limits and not all landing brakes are the same.Just thinking about this issue causes me to consider solutions. Yeah, I do that. I'm also a software architect / engineer. Makes for interesting thoughts. For the electric speed brake actuator, perhaps some "intelligence" is called for. Now, I'm not much good with electronics, so I can have the idea, but would be lousy for implementing solutions. How about disabling the "down" direction above some selected speed, say the 95 KIAS Terry mentioned? You'd not want to disable the "up" direction, for obvious reasons. Doable? Well, that smart phone everyone is carrying around has way more compute capability than most realize. Just wondering if we use smart phones why we don't also use smart airplanes? Of course one would want to avoid any 737 MAX syndromes .... -- David Froble Tel: 724-529-0450 Dave Froble Enterprises, Inc. E-Mail: davef@... DFE Ultralights, Inc. 170 Grimplin Road Vanderbilt, PA 15486
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Re: [1 Attachment]
Terry Schubert
While the landing brake is strong, it does have limits and not all landing brakes are the same.
The original landing brake design was manually operated and manual extension at high speed was VERY difficult. With the electric actuators, the extension speed goes WAY up and can be extended at structure failing speeds. There was a mod put out to reinforce the brake with extra glass and the foam was injected with resin. If you did not build your airplane it may not have the upgraded strength mod so until you know for sure you'd be wise to follow the RAF published limits of 95 KIAS. After the initial bang, things will get really quiet if the landing brake goes through the prop. Terry Schubert Central States Association Newsletter Editor
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Re: [1 Attachment]
Lew Miller
I lowered mine accidentally at 140 kias in turbulence in western Kansas coming back from OSH. The fuse popped with the brake down. The fuses are under my left thigh. I flew 50 nm at 90 kias wondering if there was damage and whether I should just find a road. The brake was fine though. I had just added armpit air scoops so cooling was OK too. But 90 kias is slow going cross country. When I got back home I put a small ckt breaker right next to the brake switch. Lew Miller NX776LE
On Sunday, May 5, 2019, 5:48:03 PM PDT, Bob Holliston bob.holliston@... [canard-aviators] wrote:
Awhile back I mentioned that I had accidentally lowered my (electric) speed brake at over 200 MPH (what's that rumbling noise? LOL) The explanation being when I was flying off the 40 hours I had only the stock pitch trim system. So at anything over 170 MPH I had to be pushing forward on the stick. Well, the S/B buttons were on the stick and …. you know. My plane is in my shop for a paint job and today I removed the speed brake and found this crack pretty much exactly where you would expect it to be. I sanded the micro off in that area and couldn't find any crack in the glass. I put a couple layers of glass in that area anyway JIC. Man, these speed brakes are STRONG. I'd love to have a GoPro of the S/B to see how far it was bent back to crack the micro.
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Re: GPS Antenna
Marc J. Zeitlin
Don Jones wrote : >Thanks Mark... Whomever that is :-). > ... but the GPS receiver that I have is based on this Accord Card, now owned by > Aspen. https://aspennexnav.com/products/?cat=cca#nexnav-max ... Aha. More information leads to more useful answers. I'd contact them to ask which antennae will work with their system. >I doubt that I could ever qualify for IFR Certification due to my bad hearing, but > I do want to learn how to fly the approaches in case of an emergency. For emergency usage, I know that both Dynon and Garmin have approach databases built into their systems and can use their own GPS antenna as the sources. Not legal, but will most certainly work in an emergency, whether or not they meet TSO requirements, and great for practice approaches. I would expect that the default GRT system would do the same, if they want to be at all competitive with the newer systems that Dynon and Garmin have released. > I will report back should GRT have anything new to say about this receiver. It will be interesting to hear.
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Re: GPS Antenna
Bob Holliston
Don, I feel your pain about buying avionics a (little) too soon. There's a guy at my airport that's been working on a Wheeler Express for about 25 years. He bought all the avionics at least 15 years ago. I doubt it'll ever fly. You're at least better off than him by far. I've built two LongEZ's and the best advice I can give is to not even THINK about avionics till all the body work is done through primer. Maybe engine installation too.
On Sat, May 11, 2019 at 4:12 PM DON JONES djonesdnd@... [canard-aviators] <canard-aviators@...> wrote:
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Re: GPS Antenna
DON JONES <djonesdnd@...>
Thanks Mark, but the GPS receiver that I have is based on this Accord Card, now owned by Aspen. https://aspennexnav.com/products/?cat=cca#nexnav-max I purchased this along with my other avionics in a package deal a few years ago thinking I would be flying soon, what a laugh. Although GRT displayed this receiver a few times at Oshkosh it has never appeared in their product pages. You had to request it. This Receiver is different from the Safe-Fly and at the time was a few thousand less expensive than Garmin boxes as it is a remote located box which uses the EFIS as it's display and control. I made the purchase as it wasn't much more when taking into consideration that it would also serve as the position source for ADS-b out. I doubt that I could ever qualify for IFR Certification due to my bad hearing, but I do want to learn how to fly the approaches in case of an emergency. I will report back should GRT have anything new to say about this receiver.
On Saturday, May 11, 2019, 2:42:48 PM EDT, marc_zeitlin@... [canard-aviators] wrote:
Don Jones wrote: > I have GRT 10" HXr systems installed in my panels, the LPV GPS box has a GRT label > which utilizes an Accord Technology Card which is good down to 200' minamun approaches. So this page: seems to indicate that the legality of this system for IFR approaches is uncertain at best and that:
Good luck with "verifying and documenting that it performs within the TSO specifications". In any case, that same page then points to what GPS source to use, and discusses that only the GRT "Safe-Fly" system meets the requirements and is compatible: So, if _I_ were considering installing this possibly quasi-legal system in my plane, it seems as though this is the only GPS source that would be compatible and possible to use to even consider having a working and legal system. That's _MY_ interpretation of what GRT states publicly. Given my previous experiences and my customer's experiences with GRT equipment, the claim that they've "designed it to conform" is not particularly meaningful, without the actual certification, and since the onus is on YOU - the owner/operator - to verify and document, this is not the system _I'D_ be staking my life on in IMC conditions (even if you wanted to forget the legality of the issue). Maybe I'm missing something, but that's what I could find on the GRT web pages. Now, if you're only talking about VOR/LOC/ILS capability, then you're fine and legal, but in that case, it doesn't make any difference what GPS you're using, as it's not the primary source of navigation. My $0.02.
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Hal Hunt Exhaust
Scott Torneten <sctorneten@...>
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Re: "Coil suppression can reduce relay life"
Jack Wilhelmson
Master solenoid failure is very common when using the traditional circuit that feeds the starter solenoid (200amp intermittent ratting) current through the master solenoid (30 amp continuous rattng). This subject has been discussed on the Cozy forum. Regards Jack Wilhelmson
On Sat, May 11, 2019 at 1:01 PM Bill Allen billallensworld@... [canard-aviators] <canard-aviators@...> wrote:
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Re: GPS Antenna
Marc J. Zeitlin
Don Jones wrote:
> I have GRT 10" HXr systems installed in my panels, the LPV GPS box has a GRT label > which utilizes an Accord Technology Card which is good down to 200' minamun approaches. So this page: seems to indicate that the legality of this system for IFR approaches is uncertain at best and that:
Good luck with "verifying and documenting that it performs within the TSO specifications". In any case, that same page then points to what GPS source to use, and discusses that only the GRT "Safe-Fly" system meets the requirements and is compatible: So, if _I_ were considering installing this possibly quasi-legal system in my plane, it seems as though this is the only GPS source that would be compatible and possible to use to even consider having a working and legal system. That's _MY_ interpretation of what GRT states publicly. Given my previous experiences and my customer's experiences with GRT equipment, the claim that they've "designed it to conform" is not particularly meaningful, without the actual certification, and since the onus is on YOU - the owner/operator - to verify and document, this is not the system _I'D_ be staking my life on in IMC conditions (even if you wanted to forget the legality of the issue). Maybe I'm missing something, but that's what I could find on the GRT web pages. Now, if you're only talking about VOR/LOC/ILS capability, then you're fine and legal, but in that case, it doesn't make any difference what GPS you're using, as it's not the primary source of navigation. My $0.02.
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Re: GPS Antenna
DON JONES <djonesdnd@...>
I have GRT 10" HXr systems installed in my panels, the LPV GPS box has a GRT label which utilizes an Accord Technology Card which is good down to 200' minamun approaches. It didn't come with an antenna. So, I'm guessing I am free to use any TSO C190 GPS antenna, just wondering what the rest of you are using. I have an inquiry into GRT Support, but I doubt I will hear back until sometime next week. I would like to build my antenna holder this weekend, but need to know the size of the thing because space over the Canard is limited. Thanks for your input, Don
On Saturday, May 11, 2019, 8:40:58 AM PDT, Buly bulent.enginegear@... [canard-aviators] wrote:
What Marc said. I installed Garmin GTN-625 in my CZ and it came with “shark fin” antenna. It needed a ground plane and mounted on the outside. Not even paint is allowed on the antenna.
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Re: "Coil suppression can reduce relay life"
Bill Allen
Having had master contractors fail on me in certified aircraft, I am seriously contemplating replacing an electromechanical (traditional master solenoid) with a simple mechanical one, which, as a bonus, doesn’t consume power ( about 1.5a) Flaming River do a range of these devices; and, for Education and Recreation, could provide a simpler solution in an experimental aircraft. Bill Allen
On Sat, 11 May 2019 at 18:40, Mike Satchell mike.satch@... [canard-aviators] <canard-aviators@...> wrote:
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Re: "Coil suppression can reduce relay life"
Mike Satchell
Jack, The starter solenoid is my highest concern regarding this topic. It's not uncommon for them to fail and sometimes, it is a catastrophic event. An increased breaking force (faster drop out) should decrease the likelihood of welded contacts. Regards, Mike Satchell
On 5/11/2019 10:42 AM, jack711cz eznoselift@...
[canard-aviators] wrote:
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Re: "Coil suppression can reduce relay life"
Jack Wilhelmson
MIke: Your missing the point here. The point is relay reliability, not drop out time. Regards Jack Wilhelmson
On Sat, May 11, 2019 at 10:39 AM Mike Satchell mike.satch@... [canard-aviators] <canard-aviators@...> wrote:
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Re: GPS Antenna
Bulent Aliev
What Marc said. I installed Garmin GTN-625 in my CZ and it came with “shark fin” antenna. It needed a ground plane and mounted on the outside. Not even paint is allowed on the antenna.
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