---------------------------------------------------------- JabiruEngine-List Digest Archive --- Total Messages Posted Sun 03/23/08: 18 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:16 AM - Re: Re: Wiring 3300 to an alternator switch (Peter Harris) 2. 12:56 AM - Re: Wiring 3300 to an alternator switch (jetboy) 3. 04:11 AM - Re: Re: Wiring 3300 to an alternator switch (Gilles Thesee) 4. 05:22 AM - Re: Re: Wiring 3300 to an alternator switch (BobsV35B@aol.com) 5. 06:08 AM - Re: Re: Wiring 3300 to an alternator switch (BobsV35B@aol.com) 6. 06:18 AM - Re: Re: Wiring 3300 to an alternator switch (BobsV35B@aol.com) 7. 02:56 PM - Re: Re: Wiring 3300 to an alternator switch (Noel Loveys) 8. 03:38 PM - Re: Re: Wiring 3300 to an alternator switch (Peter Harris) 9. 04:44 PM - Re: Re: Wiring 3300 to an alternator switch (Noel Loveys) 10. 05:49 PM - Re: Re: Wiring 3300 to an alternator switch (BobsV35B@aol.com) 11. 06:48 PM - Re: Re: Wiring 3300 to an alternator switch (JOSEPH MATHIAS LINDA MATHIAS) 12. 06:50 PM - Re: Re: Wiring 3300 to an alternator switch (JOSEPH MATHIAS LINDA MATHIAS) 13. 07:22 PM - Re: Re: Wiring 3300 to an alternator switch (BobsV35B@aol.com) 14. 07:40 PM - Re: Wiring 3300 to an alternator switch (jetboy) 15. 08:16 PM - Re: Re: Wiring 3300 to an alternator switch (BobsV35B@aol.com) 16. 08:55 PM - Re: Re: Wiring 3300 to an alternator switch (Peter Harris) 17. 09:11 PM - Re: Re: Wiring 3300 to an alternator switch (Fiveonepw@aol.com) 18. 10:39 PM - Re: Wiring 3300 to an alternator switch (jetboy) ________________________________ Message 1 _____________________________________ Time: 12:16:57 AM PST US From: "Peter Harris" Subject: RE: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Hi Bob, My knowledge is a bit patchy. The best source for good info is aeroelectrics list found in the Matronics group or you could Google for Bob Nucholls Aeroelectric Connection. He has a diagram for the crowbar over voltage protection (OV) which disconnects a runaway alternator if the regulator should fail. Then the life of the alternator would depend on the mode of failure. Normally overvoltage goes to earth through the regulator but if the Reg. went OC and with no OV protection then your main bus will be exposed to the unregulated alternator output which goes up to 60VAC There is also another alternative circuit which could be used for OV protection and which would allow the alternator to remain connected. Basically this alternative OV circuit is like a supplementary regulator which starts to work if the supply voltage goes above 15V. Old Peter (1938 vintage) _____ From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of BobsV35B@aol.com Sent: Sunday, 23 March 2008 11:24 AM Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Evening Peter, Thanks for the information. Do most Jabiru operators use some sort of over voltage protection? Is there a common method that has been successful? As I am sure you can tell, my knowledge in this area is woefully inadequate. Are there any good sources of data that I can study? If a contactor was opened by a crowbar or other over voltage protection such that it would save the electronics, would the alternator still be damaged or is there some modality that would cause it to reduce it's output? Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 In a message dated 3/22/2008 7:51:24 P.M. Central Daylight Time, peterjfharris@bigpond.com writes: Bob, You are right about the excess current it is taken to earth at the base of the regulator which should be mounted on a heat sink panel. AC output from the PM alternator varies with RPM and the excess energy is bled off to earth during the rectification/regulation process. It sounds a bit primitive but it is simple and effective. Over voltage protection is worthwhile in case the regulator burns out. Peter H _____ Create a Home Theater Like the Pros. Watch the video on AOL Home. ________________________________ Message 2 _____________________________________ Time: 12:56:02 AM PST US Subject: JabiruEngine-List: Re: Wiring 3300 to an alternator switch From: "jetboy" Bob if I can help explain the type of system used by Jabiru I hope it aids your wiring choice. Some texts refer to the PMA as a dynamo. The Jabiru assembly is similar to most Japanese and Harley motorcyles- not the old brit bikes that used Lucas -the prince of darkness- electrics. Early 3300 used a 3-phase stator, which requires a six diode rectifier stack like most automotive "alternators" have. In theory, this is much better for the output filtering because the ripple from a 3 phase is much less than the "on-off" flow from a single phase winding. Old motorcycles and Rotax 2 strokes used a shunt regulator to limit the output. This was in the form of a selenium pile mounted under the headlight for cooling on the bikes or a triggered diode (SCR) switch module on the rotax. When the output got above 14 volts the shunt device would load the stator windings and the current would be limited by the available magnet strength. the Rotax units had a habbit of failing open circuit leaving 50 volts to burn up whatever I had connected downstream. You can choose a linear series regulator, Powermate or B+C LR3 come to mind. The limitation on these is that they are, much like a carbon pile, in the line and reduce the current by turning it to heat. The big advantage is the output is much cleaner. If they fail it will usually be short cct and that is not favourable to your avionics, so these normally need or incorporate some overvoltage crowbar. Newer motorcycles, Jabiru and i believe Rotax 912 use a series switching regulator. That is, when the transistors see the voltage applied to the yellow 'sense' wire is lower than the internally preset reference voltage, the bridge rectifier is triggered on. this is by activation of the two SCRs that are in the -ve legs of the bridge. The SCR that is conducting remains conducting until the end of the AC cycle coming from the stator windings, at this time the SCR remains non conducting unless there is a fresh trigger from the transistors that sense the voltage. The advantage of this regulator is that no current is dumped to ground, and as it is switching on it does not get hot. It is either on or off. the battery has to absorb the excess of the 'on' pulse which can be a problem if you run without battery connected or with sense wire disconnected. SCRs usually fail 'open cct' so there will be no output hence there is little need for other overvolt protection, so long as the sense wire is ALLWAYS in connection with the output wire. If you wish to be able to turn off the PMA, I would suggest switching one of the AC stator wires. The Jabiru manual is not very clear here, in 3 places it shows different recommendations. I would follow the text that calls for yellow and red to be joined and connected direct to battery studs, or via a fuse link (this is a bolted fuse element or a short crimped thin wire in the engine bay- you cannot fix a problem of a magnitude that would cause this fuse to blow anyway) If you wish to use the 'charge fail' lamp facility as depicted in the sample wiring schematic for J250 aircraft, you will then need to disconnect some of the regulator from the battery via the master switch. My option would be to use a double pole master and wire the lamp via the spare pole. This would avoid flat battery whilst preserving the direct regulator-battery connection. Dont blame me if you did it another way and have burnt parts! Regards, Ralph telecommunications engineering is my day job part-time avionics and PT6 instrumentation troubleshooter CH701 with Jabiru 2200a and yes I have a turbine and it DOES have a PMA. came off an A7 -------- Ralph - CH701 / 2200a Read this topic online here: http://forums.matronics.com/viewtopic.php?p=171885#171885 ________________________________ Message 3 _____________________________________ Time: 04:11:40 AM PST US From: Gilles Thesee Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Noel Loveys a crit : > > Generators and magnetos are somewhat limited in their capacity to > generate electrical power so over voltage is not generally a > consideration. > Noel and all, Whereas I would second you on the self limited *current* capacity of permanent magnet alternators, I beg to differ on the over *voltage* issue : a PM alternator cannot prevent from producing voltage when spinning, and if the regulator fails, voltage may climb as up as 80-100 volts according to model and rpm. A good battery may temporarily soak the voltage excursion, but those values are sufficient to damage any avionics if not taken care of on time. So overvoltage protection is worth some consideration if expensive avionics is installed. As mentioned elsewhere, the Aeroelectric website and list provide really valuable information and circuit architecture suggestions. The experience an knowledge there are hard to beat. FWIW Best regards, -- Gilles http://contrails.free.fr ________________________________ Message 4 _____________________________________ Time: 05:22:24 AM PST US From: BobsV35B@aol.com Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Morning Noel, I did look at the list of revised pages and they show ALL pages as having been revised! I don't mind the paper so much, but all that ink! Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 Do Not Archive In a message dated 3/22/2008 11:07:43 P.M. Central Daylight Time, noelloveys@yahoo.ca writes: Great! Have look at the list of revised pages which follows the table of contents. It will give you a list of all the updated and added pages... Saves wear and tear on the printer, paper and cartridges. You may have to make notes of the different pages you will need and print only those pages... The old pages can go in the bottom of the bird cage. Noel **************Create a Home Theater Like the Pros. Watch the video on AOL Home. (http://home.aol.com/diy/home-improvement-eric-stromer?video=15?ncid=aolhom00030000000001) ________________________________ Message 5 _____________________________________ Time: 06:08:33 AM PST US From: BobsV35B@aol.com Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Morning Peter, I have been monitoring the matronics list for several years and 'Lectric Bob for at least twenty years. I do have several copies of the Connection plus it's predecessor from the Down By The Riverside Press!. I even attended one of his seminars a year or so ago. That is probably why I am so concerned as to how the permanent magnet alternator can be deactivated so that it will not fry the electronics nor tear itself apart. I think I do understand the use of a crow bar to save the panel, but the runaway alternator has me concerned. I had no idea there was such a thing available as a permanent magnet alternator. I guess every time it was mentioned, I disregarded and skipped over it because I worked only on military and certified aircraft electrical systems. Never messed with outboards, lawn mowers or snow mobiles. Thanks for all the help you and others have provided. Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 In a message dated 3/23/2008 2:17:40 A.M. Central Daylight Time, peterjfharris@bigpond.com writes: Hi Bob, My knowledge is a bit patchy. The best source for good info is aeroelectrics list found in the Matronics group or you could Google for Bob Nucholls Aeroelectric Connection. He has a diagram for the crowbar over voltage protection (OV) which disconnects a runaway alternator if the regulator should fail. Then the life of the alternator would depend on the mode of failure. Normally overvoltage goes to earth through the regulator but if the Reg. went OC and with no OV protection then your main bus will be exposed to the unregulated alternator output which goes up to 60VAC There is also another alternative circuit which could be used for OV protection and which would allow the alternator to remain connected. Basically this alternative OV circuit is like a supplementary regulator which starts to work if the supply voltage goes above 15V. Old Peter (1938 vintage) **************Create a Home Theater Like the Pros. Watch the video on AOL Home. (http://home.aol.com/diy/home-improvement-eric-stromer?video=15?ncid=aolhom00030000000001) ________________________________ Message 6 _____________________________________ Time: 06:18:16 AM PST US From: BobsV35B@aol.com Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Morning Ralph, That helps a lot! My learning curve is still on the way up. Your fine explanation has been printed and added to the manual. Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 Do Not Archive In a message dated 3/23/2008 2:56:52 A.M. Central Daylight Time, sanson.r@xtra.co.nz writes: Bob if I can help explain the type of system used by Jabiru I hope it aids your wiring choice. **************Create a Home Theater Like the Pros. Watch the video on AOL Home. (http://home.aol.com/diy/home-improvement-eric-stromer?video=15?ncid=aolhom00030000000001) ________________________________ Message 7 _____________________________________ Time: 02:56:11 PM PST US From: "Noel Loveys" Subject: RE: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Thanks Ralph: It's always good to learn more. I was under the understanding that the carbon pile actually lowered the voltage when it came into problems.,, Which were generally crystallization of the piles. I can see the switching one of the stator wires but couldn't see the advantage of that. Does your turbine produce 400 Hz three phase?? Noel -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of jetboy Sent: Sunday, March 23, 2008 5:23 AM Subject: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Bob if I can help explain the type of system used by Jabiru I hope it aids your wiring choice. Some texts refer to the PMA as a dynamo. The Jabiru assembly is similar to most Japanese and Harley motorcyles- not the old brit bikes that used Lucas -the prince of darkness- electrics. Early 3300 used a 3-phase stator, which requires a six diode rectifier stack like most automotive "alternators" have. In theory, this is much better for the output filtering because the ripple from a 3 phase is much less than the "on-off" flow from a single phase winding. Old motorcycles and Rotax 2 strokes used a shunt regulator to limit the output. This was in the form of a selenium pile mounted under the headlight for cooling on the bikes or a triggered diode (SCR) switch module on the rotax. When the output got above 14 volts the shunt device would load the stator windings and the current would be limited by the available magnet strength. the Rotax units had a habbit of failing open circuit leaving 50 volts to burn up whatever I had connected downstream. You can choose a linear series regulator, Powermate or B+C LR3 come to mind. The limitation on these is that they are, much like a carbon pile, in the line and reduce the current by turning it to heat. The big advantage is the output is much cleaner. If they fail it will usually be short cct and that is not favourable to your avionics, so these normally need or incorporate some overvoltage crowbar. Newer motorcycles, Jabiru and i believe Rotax 912 use a series switching regulator. That is, when the transistors see the voltage applied to the yellow 'sense' wire is lower than the internally preset reference voltage, the bridge rectifier is triggered on. this is by activation of the two SCRs that are in the -ve legs of the bridge. The SCR that is conducting remains conducting until the end of the AC cycle coming from the stator windings, at this time the SCR remains non conducting unless there is a fresh trigger from the transistors that sense the voltage. The advantage of this regulator is that no current is dumped to ground, and as it is switching on it does not get hot. It is either on or off. the battery has to absorb the excess of the 'on' pulse which can be a problem if you run without battery connected or with sense wire disconnected. SCRs usually fail 'open cct' so there will be no output hence there is little need for other overvolt protection, so long as the sense wire is ALLWAYS in connection with the output wire. If you wish to be able to turn off the PMA, I would suggest switching one of the AC stator wires. The Jabiru manual is not very clear here, in 3 places it shows different recommendations. I would follow the text that calls for yellow and red to be joined and connected direct to battery studs, or via a fuse link (this is a bolted fuse element or a short crimped thin wire in the engine bay- you cannot fix a problem of a magnitude that would cause this fuse to blow anyway) If you wish to use the 'charge fail' lamp facility as depicted in the sample wiring schematic for J250 aircraft, you will then need to disconnect some of the regulator from the battery via the master switch. My option would be to use a double pole master and wire the lamp via the spare pole. This would avoid flat battery whilst preserving the direct regulator-battery connection. Dont blame me if you did it another way and have burnt parts! Regards, Ralph telecommunications engineering is my day job part-time avionics and PT6 instrumentation troubleshooter CH701 with Jabiru 2200a and yes I have a turbine and it DOES have a PMA. came off an A7 -------- Ralph - CH701 / 2200a Read this topic online here: http://forums.matronics.com/viewtopic.php?p=171885#171885 ________________________________ Message 8 _____________________________________ Time: 03:38:50 PM PST US From: "Peter Harris" Subject: RE: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Gilles and Ralph, If the J3300 is fitted with a series switching regulator does this mean that the alternator AC output is switched on or off the bridge connection and it would go OC when the battery is fully charged and there is no load dumping to earth? Does this mean that the regulator is safe and does not require OV protection or do we need OV protection for interruption of a heavy DC current on the busbar side? Thanks, Peter H ( I suppose this should be on the aeroelectrics list) -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of jetboy Sent: Sunday, 23 March 2008 5:53 PM Subject: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Bob if I can help explain the type of system used by Jabiru I hope it aids your wiring choice. Some texts refer to the PMA as a dynamo. The Jabiru assembly is similar to most Japanese and Harley motorcyles- not the old brit bikes that used Lucas -the prince of darkness- electrics. Early 3300 used a 3-phase stator, which requires a six diode rectifier stack like most automotive "alternators" have. In theory, this is much better for the output filtering because the ripple from a 3 phase is much less than the "on-off" flow from a single phase winding. Old motorcycles and Rotax 2 strokes used a shunt regulator to limit the output. This was in the form of a selenium pile mounted under the headlight for cooling on the bikes or a triggered diode (SCR) switch module on the rotax. When the output got above 14 volts the shunt device would load the stator windings and the current would be limited by the available magnet strength. the Rotax units had a habbit of failing open circuit leaving 50 volts to burn up whatever I had connected downstream. You can choose a linear series regulator, Powermate or B+C LR3 come to mind. The limitation on these is that they are, much like a carbon pile, in the line and reduce the current by turning it to heat. The big advantage is the output is much cleaner. If they fail it will usually be short cct and that is not favourable to your avionics, so these normally need or incorporate some overvoltage crowbar. Newer motorcycles, Jabiru and i believe Rotax 912 use a series switching regulator. That is, when the transistors see the voltage applied to the yellow 'sense' wire is lower than the internally preset reference voltage, the bridge rectifier is triggered on. this is by activation of the two SCRs that are in the -ve legs of the bridge. The SCR that is conducting remains conducting until the end of the AC cycle coming from the stator windings, at this time the SCR remains non conducting unless there is a fresh trigger from the transistors that sense the voltage. The advantage of this regulator is that no current is dumped to ground, and as it is switching on it does not get hot. It is either on or off. the battery has to absorb the excess of the 'on' pulse which can be a problem if you run without battery connected or with sense wire disconnected. SCRs usually fail 'open cct' so there will be no output hence there is little need for other overvolt protection, so long as the sense wire is ALLWAYS in connection with the output wire. If you wish to be able to turn off the PMA, I would suggest switching one of the AC stator wires. The Jabiru manual is not very clear here, in 3 places it shows different recommendations. I would follow the text that calls for yellow and red to be joined and connected direct to battery studs, or via a fuse link (this is a bolted fuse element or a short crimped thin wire in the engine bay- you cannot fix a problem of a magnitude that would cause this fuse to blow anyway) If you wish to use the 'charge fail' lamp facility as depicted in the sample wiring schematic for J250 aircraft, you will then need to disconnect some of the regulator from the battery via the master switch. My option would be to use a double pole master and wire the lamp via the spare pole. This would avoid flat battery whilst preserving the direct regulator-battery connection. Dont blame me if you did it another way and have burnt parts! Regards, Ralph telecommunications engineering is my day job part-time avionics and PT6 instrumentation troubleshooter CH701 with Jabiru 2200a and yes I have a turbine and it DOES have a PMA. came off an A7 -------- Ralph - CH701 / 2200a Read this topic online here: http://forums.matronics.com/viewtopic.php?p=171885#171885 ________________________________ Message 9 _____________________________________ Time: 04:44:58 PM PST US From: "Noel Loveys" Subject: RE: JabiruEngine-List: Re: Wiring 3300 to an alternator switch To be honest I didn't look at the list of revised pages... Happy printing... I hate the cost of cartridges too. Noel From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of BobsV35B@aol.com Sent: Sunday, March 23, 2008 9:49 AM Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Morning Noel, I did look at the list of revised pages and they show ALL pages as having been revised! I don't mind the paper so much, but all that ink! Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 Do Not Archive In a message dated 3/22/2008 11:07:43 P.M. Central Daylight Time, noelloveys@yahoo.ca writes: Great! Have look at the list of revised pages which follows the table of contents. It will give you a list of all the updated and added pages... Saves wear and tear on the printer, paper and cartridges. You may have to make notes of the different pages you will need and print only those pages... The old pages can go in the bottom of the bird cage. Noel _____ Create a Home Theater Like the Pros. Watch the video on AOL Home. ________________________________ Message 10 ____________________________________ Time: 05:49:18 PM PST US From: BobsV35B@aol.com Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Evening Noel, All 110 pages have been revised, the bulletins brought up to date, and we will be heading to Texas tomorrow to help our Granddaughter install the 3300 Jabiru engine in her Quick Built Legend Cub! Thanks for all the help from everyone. I have learned a lot about permanent magnet alternators in the last few days. Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Do Not Archive Brookeridge Air Park LL22 In a message dated 3/23/2008 6:45:49 P.M. Central Daylight Time, noelloveys@yahoo.ca writes: To be honest I didn=99t look at the list of revised pages... Happy printing... I hate the cost of cartridges too. Noel **************Create a Home Theater Like the Pros. Watch the video on AOL Home. (http://home.aol.com/diy/home-improvement-eric-stromer?video=15?ncid=aol hom00030000000001) ________________________________ Message 11 ____________________________________ Time: 06:48:43 PM PST US From: "JOSEPH MATHIAS LINDA MATHIAS" Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch ----- Original Message ----- From: Noel Loveys To: jabiruengine-list@matronics.com Sent: Sunday, March 23, 2008 7:41 PM Subject: RE: JabiruEngine-List: Re: Wiring 3300 to an alternator switch To be honest I didn't look at the list of revised pages... Happy printing... I hate the cost of cartridges too. Noel From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of BobsV35B@aol.com Sent: Sunday, March 23, 2008 9:49 AM To: jabiruengine-list@matronics.com Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Morning Noel, I did look at the list of revised pages and they show ALL pages as having been revised! I don't mind the paper so much, but all that ink! Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 Do Not Archive In a message dated 3/22/2008 11:07:43 P.M. Central Daylight Time, noelloveys@yahoo.ca writes: Great! Have look at the list of revised pages which follows the table of contents. It will give you a list of all the updated and added pages... Saves wear and tear on the printer, paper and cartridges. You may have to make notes of the different pages you will need and print only those pages... The old pages can go in the bottom of the bird cage. Noel ------------------------------------------------------------------------- ----- Create a Home Theater Like the Pros. Watch the video on AOL Home. http://www.matronics.com/Navigator?JabiruEngine-Listhttp://forums.matroni cs.comhttp://www.matronics.com/contribution ________________________________ Message 12 ____________________________________ Time: 06:50:25 PM PST US From: "JOSEPH MATHIAS LINDA MATHIAS" Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Hey guys, Try www.inksell.com for good prices on printer cartridges; they are much cheaper than those you buy in any store. They aren't the printer mfgr brand but I have had no problem for the past couple years I have been using them. Linda ----- Original Message ----- From: Noel Loveys To: jabiruengine-list@matronics.com Sent: Sunday, March 23, 2008 7:41 PM Subject: RE: JabiruEngine-List: Re: Wiring 3300 to an alternator switch To be honest I didn't look at the list of revised pages... Happy printing... I hate the cost of cartridges too. Noel From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of BobsV35B@aol.com Sent: Sunday, March 23, 2008 9:49 AM To: jabiruengine-list@matronics.com Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Morning Noel, I did look at the list of revised pages and they show ALL pages as having been revised! I don't mind the paper so much, but all that ink! Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 Do Not Archive In a message dated 3/22/2008 11:07:43 P.M. Central Daylight Time, noelloveys@yahoo.ca writes: Great! Have look at the list of revised pages which follows the table of contents. It will give you a list of all the updated and added pages... Saves wear and tear on the printer, paper and cartridges. You may have to make notes of the different pages you will need and print only those pages... The old pages can go in the bottom of the bird cage. Noel ------------------------------------------------------------------------- ----- Create a Home Theater Like the Pros. Watch the video on AOL Home. http://www.matronics.com/Navigator?JabiruEngine-Listhttp://forums.matroni cs.comhttp://www.matronics.com/contribution ________________________________ Message 13 ____________________________________ Time: 07:22:21 PM PST US From: BobsV35B@aol.com Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Evening Peter, Just a bit of information if you will. What is an SCR? Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 In a message dated 3/23/2008 5:39:47 P.M. Central Daylight Time, peterjfharris@bigpond.com writes: Newer motorcycles, Jabiru and i believe Rotax 912 use a series switching regulator. That is, when the transistors see the voltage applied to the yellow 'sense' wire is lower than the internally preset reference voltage, the bridge rectifier is triggered on. this is by activation of the two SCRs that are in the -ve legs of the bridge. The SCR that is conducting remains conducting until the end of the AC cycle coming from the stator windings, at this time the SCR remains non conducting unless there is a fresh trigger from the transistors that sense the voltage. **************Create a Home Theater Like the Pros. Watch the video on AOL Home. (http://home.aol.com/diy/home-improvement-eric-stromer?video=15?ncid=aolhom00030000000001) ________________________________ Message 14 ____________________________________ Time: 07:40:48 PM PST US Subject: JabiruEngine-List: Re: Wiring 3300 to an alternator switch From: "jetboy" Peter & Noel If I wanted to disable the alternator I would switch the AC off rather than the rectified and regulated DC. 3 reasons: switching the DC does not isolate your windings from burning up. Switching the DC involves another infirm connection and much longer path to the battery. The rating of the switch required is lower and the AC line is prior to the regulator so any voltage drops are not affecting the output. The series switching regulator, when up to full voltage on the DC bus, is OC, and the AC available from the PMA is not consumed. The windings stay cool, and there is no load on the engine because the magnets are passing a coil that is not connected anywhere. If wired in a safe configuration and with a battery or capacitor across the output it should not need any further OV protection. Interrupting a heavy load off the DC bus will not cause the regulator do go OV. Anytime the sense wire is not directly connected to the output, you need another form of protection, because the voltage control loop is open, and like an automotive alternator, full output will be made available to all in its path. Bob's aerolectric Z20 looks to be a safe method, and has the fusible links to isolate any faulty units from further harm. Ralph. PS the turbine with a PMA is a JFS100 APU, the alternator is for 24 volts @ 4 amps and only uses a rectifier. It gives me no trouble, but the igniter box is another story..... Peter H wrote: > Gilles and Ralph, > If the J3300 is fitted with a series switching regulator does this mean that > the alternator AC output is switched on or off the bridge connection and it > would go OC when the battery is fully charged and there is no load dumping > to earth? > Does this mean that the regulator is safe and does not require OV protection > or do we need OV protection for interruption of a heavy DC current on the > busbar side? > > Thanks, > Peter H ( I suppose this should be on the aeroelectrics list) > > > -- -------- Ralph - CH701 / 2200a Read this topic online here: http://forums.matronics.com/viewtopic.php?p=172101#172101 ________________________________ Message 15 ____________________________________ Time: 08:16:16 PM PST US From: BobsV35B@aol.com Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Evening Ralph, In the paragraph below, what does OC stand for? Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 In a message dated 3/23/2008 9:41:31 P.M. Central Daylight Time, sanson.r@xtra.co.nz writes: The series switching regulator, when up to full voltage on the DC bus, is OC, and the AC available from the PMA is not consumed. The windings stay cool, and there is no load on the engine because the magnets are passing a coil that is not connected anywhere. **************Create a Home Theater Like the Pros. Watch the video on AOL Home. (http://home.aol.com/diy/home-improvement-eric-stromer?video=15?ncid=aolhom00030000000001) ________________________________ Message 16 ____________________________________ Time: 08:55:35 PM PST US From: "Peter Harris" Subject: RE: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Bob, Better to ask Ralph, he raised it. But it is a type of transistor like a triode it will conduct when the grid voltage reaches switching level usually set at 14.5V for this application. So a voltage sensing device triggers the SCR at 14.5V and it conducts excess current to earth. "I think" Peter _____ From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of BobsV35B@aol.com Sent: Monday, 24 March 2008 12:19 PM Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch Good Evening Peter, Just a bit of information if you will. What is an SCR? Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 In a message dated 3/23/2008 5:39:47 P.M. Central Daylight Time, peterjfharris@bigpond.com writes: Newer motorcycles, Jabiru and i believe Rotax 912 use a series switching regulator. That is, when the transistors see the voltage applied to the yellow 'sense' wire is lower than the internally preset reference voltage, the bridge rectifier is triggered on. this is by activation of the two SCRs that are in the -ve legs of the bridge. The SCR that is conducting remains conducting until the end of the AC cycle coming from the stator windings, at this time the SCR remains non conducting unless there is a fresh trigger from the transistors that sense the voltage. _____ Create a Home Theater Like the Pros. Watch the video on AOL Home. ________________________________ Message 17 ____________________________________ Time: 09:11:27 PM PST US From: Fiveonepw@aol.com Subject: Re: JabiruEngine-List: Re: Wiring 3300 to an alternator switch In a message dated 03/23/2008 9:41:31 PM Central Daylight Time, sanson.r@xtra.co.nz writes: Anytime the sense wire is not directly connected to the output, you need another form of protection, because the voltage control loop is open, and like an automotive alternator, full output will be made available to all in its path. Hi Ralph- obviously you have a pretty good handle on this stuff, so could you please shed some light on one aspect I'm confused on: It is my understanding that in a PMA when a magnet passes a coil, there is some maximum amount of current induced in the coil (load-dependant, of course), based on number of coil windings and power of the magnetic field provided by the magnet. (Not sure how velocity of the passing magnetic field affects this) This results in a maximum voltage value for the given magnet/coil/(velocity?) event, and that voltage would be self-limiting, or incapable of a "runaway", which is not the case in a typical automotive-type alternator supplied by a "regulated" voltage to a field winding as mentioned above. With a PMA regulated by the device shown in the Jabiru manual, when the SCRs are triggered to charge the system because the reference voltage set point was reached, wouldn't each charging event (peak sine wave voltage achieved as magnet passes a coil with SCRs gated on) reach the maximum possible voltage based on the above situation? (I understand how a large capacitor between the alternator leads would reduce the peak-to-peak voltage, I think...) Appreciate your input on this issue- great discussion! Mark **************Create a Home Theater Like the Pros. Watch the video on AOL Home. (http://home.aol.com/diy/home-improvement-eric-stromer?video=15?ncid=aolhom00030000000001) ________________________________ Message 18 ____________________________________ Time: 10:39:52 PM PST US Subject: JabiruEngine-List: Re: Wiring 3300 to an alternator switch From: "jetboy" Mark, A couple of terms - OC means "open circuit" SCR is the abbreviation of "silicon controlled rectifier" and is a diode that will not conduct until a trigger signal is applied to the control lead, thereafter it remains conducting unless the current passing thru is all gone. This occurs when the PMA output voltage changes to the reverse polarity, as the voltage passes thru zero the SCR unlatches and remains off until another trigger voltage is applied to the gate. The generation of voltage by the PMA is limited by the number of turns on the windings, and I think the velocity of the magnets moving past. the current draw available would be determined by the rpm and strength of the magnets I expect, and these conditions will mean it is self limiting. But to get it to operate satisfactorily at say 2,000 rpm the unit will end up producing more than those requirements at 3,300 rpm. There is no need for regulating the maximum current because even shorting the windings doesnt produce much more. The voltage needs regulating for a large portion of the running especially at low loadings it will be 3 or 4 times the minimum requirement. Your last question is correct - each time the SCRs are triggered in order to let thru some more charge, the remainder of that half cycle AC is output to the load. If the load is a capacitor or battery the current is stored as a charge and the voltage rises slightly. If there is no load connected, other than your $$$ avionics, then the half cycle pulse results in a substantial voltage peak. This all happens very quickly but in most cases the internal capacitors will store it. If the avionics meet DOD-160 they will be immune. We are only talking of the part of the cycle that is over the 14 volts so the duration of these pulses will be less than one thousandth of a second. Not every cycle will be triggered and not every trigger will result in an overvolt spike because there is no timing control applied to the triggers. It is a relatively robust simple design for the purpose of charging the battery and running the lights and horn on your lawn tractor. I have measured the spikes and voltages on my 15 amp 2200a PMA and there is nothing to be concerned with. I use the PC925 26 AH battery which can accomodate most problems. The most efficient way to do this would be to fully rectify the PMA and apply the 15 - 85 volts to a switchmode inverter with a steady 13.8 volt output. These are off the shelf items but as soon as you get a bit of moisture in will probably fail so would be better off fitting a regular 3 phase alternator/regulator. - and the OV protection. Ralph could you please shed some light on one aspect I'm confused on: It is my understanding that in a PMA when a magnet passes a coil, there is some maximum amount of current induced in the coil (load-dependant, of course), based on number of coil windings and power of the magnetic field provided by the magnet. (Not sure how velocity of the passing magnetic field affects this) This results in a maximum voltage value for the given magnet/coil/(velocity?) event, and that voltage would be self-limiting, or incapable of a "runaway", which is not the case in a typical automotive-type alternator supplied by a "regulated" voltage to a field winding as mentioned above. With a PMA regulated by the device shown in the Jabiru manual, when the SCRs are triggered to charge the system because the reference voltage set point was reached, wouldn't each charging event (peak sine wave voltage achieved as magnet passes a coil with SCRs gated on) reach the maximum possible voltage based on the above situation? (I understand how a large capacitor between the alternator leads would reduce the peak-to-peak voltage, I think...) Appreciate your input on this issue- great discussion! Mark Create a Home Theater Like the Pros. Watch the video on AOL Home (http://home.aol.com/diy/home-improvement-eric-stromer?video=15?ncid=aolhom00030000000001). > [b] -------- Ralph - CH701 / 2200a Read this topic online here: http://forums.matronics.com/viewtopic.php?p=172134#172134 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message jabiruengine-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/JabiruEngine-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/jabiruengine-list Browse Digests http://www.matronics.com/digest/jabiruengine-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.