cscotthendry Posted February 20 Share Posted February 20 18 minutes ago, danny_galaga said: ... And of course to replace any crappy Italian electronics 😄 I hear you! I have an Italian GPS and it's not very good. It hangs the heading indication occasionally. I have had numerous contacts with their support people. Nice people, but not effective troubleshooters. 1 Link to comment Share on other sites More sharing options...
RFguy Posted February 20 Share Posted February 20 (edited) 2 hours ago, cscotthendry said: Rotax reccomend a capacitor between the output of the regulator and ground. An isolator on the positive terminal of the battery shouldn't be placed between these two or it negates the benefit of the capacitor. The capacitor provides a small load to the regulator to stop it from overvoltage damage if the connection between the regulator and the rest of the system is lost, most likely from the isolator switch being turned off, or a master relay failure, while the engine is running. mmmmmm some extra here 1) The capacitor is required to provide smoothing of the pulses of current that come out of the alternator. The alternator produces current pulses, and if the alternator output is not connected direct to the battery (to do the pulse smoothing) it will put alot fo noise into the harness. The capacitor is always recommended (by me) . 2) It does not put a small load on the alternator. It does NOT prevent overvoltage, what it does is smooth out the current pulses and makes the alternator output look more like DC by being a reserviour between pulses. The alternator output shoudl always go direct to the battery via a circuit breaker. The alternator regulator voltage sense wire should go to the battery or the master bus. some regulators draw a little bit of current all the time that might flatten a battery in 3 months. if you fly every 2 weeks this is no problem. if you fly every 6 months, then connect it to the master bus but you will die anyway because you are not current, so the alternator is moot. Edited February 20 by RFguy 2 1 1 Link to comment Share on other sites More sharing options...
RFguy Posted February 20 Share Posted February 20 (edited) Master isolation relays should be required mandatory on all aircraft. But its not. although in VH world (non experimental) , for a certified aircraft you will not get cert if it doesnt have one because it will not be able to meet the criteria of being able to isolate the battery. I suspect many Jabiru fires are due to no battery isolator, and watch out for Sling also, no battery isolator in at least one aircraft I have seen. The other Jab fires are probably overflowing carbs. cheap https://www.aircraftspruce.com/catalog/elpages/masterrelay.php although that one is marginal on starter current if a 3300 jab, but OK for a 4 cyl rotax/jab otherwise : https://www.aircraftspruce.com/pages/el/relays/sts-12a24a.php Edited February 20 by RFguy Link to comment Share on other sites More sharing options...
facthunter Posted February 20 Share Posted February 20 But you have the" potential" to stuff up. Regulating permanent Magnet alternators is a dark art. Nev Link to comment Share on other sites More sharing options...
danny_galaga Posted February 20 Author Share Posted February 20 1 hour ago, skippydiesel said: Hi Danny_G Would be great if you find that regulater name/supplier and put it on your "Started Spare Parts List" Yes, I probably did already 😂 Just realised I have it in my own notes: CARR5115 from vectriqparts.com.au Link to comment Share on other sites More sharing options...
Jabiru7252 Posted February 27 Share Posted February 27 On 03/07/2023 at 12:23 PM, onetrack said: Disconnecting an alternator from the battery while the alternator is producing current will cause serious damage to it, at the very least blown diodes, a damaged regulator, perhaps totally fried windings. Alternators produce high voltage AC current initially, which is converted to DC current by the regulator. A sudden disconnect of the charging circuit can see that AC current spike to unacceptably high levels, and cause damage to the alternator. Of course, a damaged alternator that needs to be replaced is a small price to pay to avoid a cabin or fuselage fire! Gee whizz, I must be silly. I thought the diodes converted the AC voltage to DC (rectification). The regulator then 'regulated' the voltage and/or current to charge the battery. The term "high voltage AC current" is meaningless to me. The alternator generates an 'alternating voltage' that when applied across a load will cause an 'alternating current' (AC) to flow. Maybe in this world of LGBT rubbish the electronic theory I was taught has been 'cancelled'. 1 Link to comment Share on other sites More sharing options...
cscotthendry Posted February 27 Share Posted February 27 1 hour ago, Jabiru7252 said: Gee whizz, I must be silly. I thought the diodes converted the AC voltage to DC (rectification). The regulator then 'regulated' the voltage and/or current to charge the battery. The term "high voltage AC current" is meaningless to me. The alternator generates an 'alternating voltage' that when applied across a load will cause an 'alternating current' (AC) to flow. Maybe in this world of LGBT rubbish the electronic theory I was taught has been 'cancelled'. What the H*ll has LGBT got to do with electrical principles? That's as specious as the "High voltage electrical current" you objected to. Disconnecting the alternator from the load causes the voltage across the induction coils in the alternator to rise past the breakdown voltage of the diodes. This causes current to flow backwards through the diodes and can cause them to fail. 1 1 Link to comment Share on other sites More sharing options...
turboplanner Posted February 27 Share Posted February 27 On 21/02/2024 at 8:56 AM, skippydiesel said: Hi Danny_G Would be great if you find that regulater name/supplier and put it on your "Started Spare Parts List" Don't do it, you'd be going off mfr specs and downgrading what was a plus feature. Link to comment Share on other sites More sharing options...
danny_galaga Posted February 27 Author Share Posted February 27 12 minutes ago, turboplanner said: Don't do it, you'd be going off mfr specs and downgrading what was a plus feature. Anything with the word DUCATI written on it is the downgrade 😀 1 Link to comment Share on other sites More sharing options...
turboplanner Posted February 27 Share Posted February 27 3 minutes ago, danny_galaga said: Anything with the word DUCATI written on it is the downgrade 😀 There is a big difference between what is a specification and what is a brand. Link to comment Share on other sites More sharing options...
danny_galaga Posted February 27 Author Share Posted February 27 (edited) 1 hour ago, turboplanner said: There is a big difference between what is a specification and what is a brand. Oh, I see. As far as I know, the reg/rec that I bought, which is made for the Rotax 912 has better specs than the original part. That is to say, it is designed as an improvement on the original. Better cooling, better electronics, simpler wiring etc. for instance, it doesn't have that strange C wire. When the engine isn't running, the regulator isn't on. It's not slowly discharging the battery.... Edited February 27 by danny_galaga 1 1 Link to comment Share on other sites More sharing options...
dtanner Posted March 2 Share Posted March 2 Hi All. Our group operates three Streak Shadow aircraft which are tandem seat pusher types. All have a mechanical isolator fitted outside the rear bulkhead to positive supply from the battery. This is connected to a 1/2" carbon fibre tube running forward through the ceiling of both cockpits, enabling either pilot or passenger to isolate the electrical system with a simple twist of the shaft. Because these aircraft are pushers, all have a reversing camera in the cockpit, giving a clear view of motor and prop operation, both day and night. If nothing else this gives peace of mind being not only able to see any issues, but to do something about it. Cheers Dave. 5 Link to comment Share on other sites More sharing options...
Roundsounds Posted March 2 Share Posted March 2 On 3/7/2023 at 10:58 AM, danny_galaga said: I only ask because an LAME apprentice was in the hanger and we were talking about it. He was pretty confident you HAVE to have on in GA, but wasn't sure about 19 rego... I’ve got a J3 Cub and don’t have any battery isolation devices. 1 4 Link to comment Share on other sites More sharing options...
danny_galaga Posted March 2 Author Share Posted March 2 21 minutes ago, Roundsounds said: I’ve got a J3 Cub and don’t have any battery isolation devices. No battery, right 😄 2 Link to comment Share on other sites More sharing options...
Roundsounds Posted March 2 Share Posted March 2 1 hour ago, danny_galaga said: No battery, right 😄 Yep! Avoids lots of issues. 2 Link to comment Share on other sites More sharing options...
Blueadventures Posted March 3 Share Posted March 3 6 hours ago, Roundsounds said: Yep! Avoids lots of issues. Except; can't turn on strobe and landing lights🤪🙃 1 Link to comment Share on other sites More sharing options...
Roundsounds Posted March 3 Share Posted March 3 11 minutes ago, Blueadventures said: Except; can't turn on strobe and landing lights🤪🙃 If you can’t see a Cub yellow Cub, you shouldn’t be flying. 😆 2 2 Link to comment Share on other sites More sharing options...
skippydiesel Posted March 3 Share Posted March 3 After "skimming" through this topic, it seems to be that the first question has been well and truly answered: Master solenoid- legal requirement in 19 reg aircraft? The answer - a master solenoid is not a legal requirement on 19 regoed aircraft but is a very good safety idea. The concept of an emergency mechanical battery isolator is excellent. Can be as simple as a panel mounted knob, connecting through a lightweight rod/cable (through the bulkhead) to a suitably sized switch mechanism (preferably on the battery(-) cable but could be on (+). The emergency activation of the isolator, will cut all battery/generator power in the aircraft, leaving the engine ignition system to continue the flight to a safe landing. Link to comment Share on other sites More sharing options...
skippydiesel Posted March 3 Share Posted March 3 5 hours ago, Blueadventures said: Except; can't turn on strobe and landing lights🤪🙃 Overrated! The hyman eye is not adapted to seeing other flying objects in the sky. That's why communication giving distance from a known point, altitude and direction of travel is so important - it gives the listener (pilot) a clue where to look, greatly assisting our poor eyesight. Aircraft lights work well in low light or against a dark sky but are otherwise almost invisible - for the VFR pilot, great fun but that's about the start/end of it. . Ground observers catch sight of an aircraft much better than when airborne. For a start they can confine their optical serch to above the horizon, then there is the noise of the aircraft engine/prop giving a general direction in which to look, if it's in the circuit, the search can be further narrowed. A VFR aircraft on the ground, may benefit from taxi lights, informing both ground and airborne observers, that the aircraft is or about to move. Link to comment Share on other sites More sharing options...
danny_galaga Posted March 3 Author Share Posted March 3 1 hour ago, skippydiesel said: After "skimming" through this topic, it seems to be that the first question has been well and truly answered: Master solenoid- legal requirement in 19 reg aircraft? The answer - a master solenoid is not a legal requirement on 19 regoed aircraft but is a very good safety idea. The concept of an emergency mechanical battery isolator is excellent. Can be as simple as a panel mounted knob, connecting through a lightweight rod/cable (through the bulkhead) to a suitably sized switch mechanism (preferably on the battery(-) cable but could be on (+). The emergency activation of the isolator, will cut all battery/generator power in the aircraft, leaving the engine ignition system to continue the flight to a safe landing. As per previous update. I ended up putting a mechanical isolator in the instrument panel 🙂 Link to comment Share on other sites More sharing options...
Jabiru7252 Posted March 3 Share Posted March 3 2 hours ago, skippydiesel said: Overrated! The hyman eye is not adapted to seeing other flying objects in the sky. That's why communication giving distance from a known point, altitude and direction of travel is so important - it gives the listener (pilot) a clue where to look, greatly assisting our poor eyesight. Aircraft lights work well in low light or against a dark sky but are otherwise almost invisible - for the VFR pilot, great fun but that's about the start/end of it. . Ground observers catch sight of an aircraft much better than when airborne. For a start they can confine their optical serch to above the horizon, then there is the noise of the aircraft engine/prop giving a general direction in which to look, if it's in the circuit, the search can be further narrowed. A VFR aircraft on the ground, may benefit from taxi lights, informing both ground and airborne observers, that the aircraft is or about to move. I'm convinced that many planes, gliders included, go into stealth mode when viewed from above. On many occasions I have tried to sight a plane that's maybe a few hundred feet below me at (say) my 3 o'clock but been absolutely unable to find it. This occurs almost exclusively over the suburbs but has also happened over dry paddocks. Another sign of old age perhaps? 1 Link to comment Share on other sites More sharing options...
skippydiesel Posted March 3 Share Posted March 3 Don't know where I got the "Hyman" from???😜 2 Link to comment Share on other sites More sharing options...
facthunter Posted March 4 Share Posted March 4 A VIRGIN Plane if you change the spelling a bit. We can all make Freudian slips. Nev 1 Link to comment Share on other sites More sharing options...
skippydiesel Posted March 4 Share Posted March 4 13 minutes ago, facthunter said: A VIRGIN Plane if you change the spelling a bit. We can all make Freudian slips. Nev Extraordinarily generous of you Nev - I make a lot of "slips"☹️ 1 Link to comment Share on other sites More sharing options...
facthunter Posted March 4 Share Posted March 4 It could have been your subconsciously religious self, associating it with Hymn? EVIL me hadn't thought of that. Nev 1 1 Link to comment Share on other sites More sharing options...
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