Jump to content

Old Koreelah

Members
  • Content Count

    4,076
  • Joined

  • Last visited

  • Days Won

    31

Old Koreelah last won the day on April 11

Old Koreelah had the most liked content!

Community Reputation

3,059 Excellent

1 Follower

About Old Koreelah

  • Rank
    Well-Known Member

More Information

  • Gender
    male
  • Location
    YQDI
  • Country
    Australia

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. Thanks for such a thorough response, OT- and for answering my questions so clearly. Home-builders like me, with limited expertise, are trying to dovetail hardware from different sources. It's a pity we can't get full and frank advice from manufacturers and suppliers - but I understand why they need to be cautious in giving out advice. In the longer term, I hope a charge-management unit like Mark Kyle describes becomes available. With so many Li batteries being fitted to homebuilts, bikes, cars, RVs, boats, etc. there sure will be a market for it In the shorter term perhaps I can fit more position lights to absorb some of the alternator's output that would otherwise be overcharging the Li battery. A simpler option is to put my old SLA battery back in. Another, messier, option is to fit the lightest SLA I can find upstream of the Li battery, to absorb the charge coming from the system and act as a "buffer" to protect it. Any thoughts?
  2. Thanks for that, Mark. I'd be very interested in what you and your guru friend's finished product. I bet there is a large and growing market for it.
  3. Quite possibly, NP- so I have to thoroughly check all wiring, The bloke at the Jab factory suggested that a bad connection on the regulator's yellow reference wire could confuse the regulator into allowing the battery to cop a 17v spike. Perhaps this causes the battery's internal BMS to disconnect until the charge voltage stabilises. I put this to the LiFePO4 battery shop and they claim the battery wouldn't disconnect. I hope to make one more test flight to induce the failure mode. I have set up a separate voltmeter so I can monitor battery voltage to see if that's where the power cut is coming from. Despite assurances from the seller that this battery is a drop-in replacement for lead acid batteries, it seems that continuous charging after it's topped up may cause long term damage. I believe the Jab generator has permanent magnets. Does that mean it doesn't need current from the battery to set up a charging field? If I disconnect the battery when it becomes fully charged, will that damage the AC generator? -
  4. Thanks for that info, 1T. I had a good look at the Redarc unit and it seems to be quite large and intended for auxiliary battery situations. My understand of electrics is limited, but isn't the Jab "alternator" actually an AC generator? If it has permanent magnets, does this mean it doesn't need a battery to create a field? If that is the case, I guess all those rally cars and everyone else who has fitted one of these is the same boat as me.
  5. As Biggles says, the engine produces its own spark, and doesn't need electrical power. But wait, BD. What you say was actually true of this plane's first engine. It had a total-loss ignition system drawing power from a small, pre-charged battery. This was topped up by a tiny solar panel mounted on the turtle deck. A previous owner said that during the ferry trip from Leeton to Wedderburn, every time he passed under a cloud the voltmeter dropped dangerously close to ignition-failure territory!
  6. Don't worry, BD. A temporary loss of electrical power doesn't threaten the safety of the aircraft. The engine keeps going and the main flight instruments are unaffected. You can fly quite safely without all the engine gauges. Some of the auxiliary gear has its own power supply, such as the radio, iPad running OzRunways, CO monitor, weather station and flight cameras. Like plenty of other little planes, this one flew for years with no electrical system at all. My main concern is that the battery or another component may be damaged if I don't find the problem and fix it. Each time I go up has been a test flight to eliminate one possibility or another.
  7. Thanks for the info, 1T. That adds to my store of knowledge, but doesn't help me find a suitable regulator. My battery supplier claims it has all necessary charging management built in, being a "drop-in replacement" for normal lead batteries. Trouble is, he's not going to divulge any details of how it works. It appears I need a regulator that will guarantee the charge voltage won't exceed 14.5v- and/or a spike arrester. Any advice welcome.
  8. I'm totally with you, 1T. After years of riding chain-driven bikes I'd had a bellyful of them, especially the oil thrown all over the frame. I got excited about the new shaft-driven bike Honda was rumoured to be developing. Apparently, as you suggest, this blank-slate project was given to a new batch of engineers. The CX-500 they came out with was pretty revolutionary. I got to ride the very first one in the country (the Black Shadow used in the ads) before it was given to some of the journos, one of whom pranged it. The one I bought was the most dependable bike I ever owned. It had some quirky features but was so well-engineered that many are still on the road today. Some of these engines are running aircraft.
  9. This has firmed as a possible course of action, but which regulator should I replace it with? The Power Mate bloke has replied to my emails and says his unit is definitely not suited to my Lipo battery. Lots of net research later, I'm learning a bit about the charging needs of these batteries, but haven't discovered any recommendation about what regulator to fit. Among the good advice found: It's not a bad idea to check the continuity / quality of the connection between the regulator and the power bus. Dodgy connections can confuse the regulator and send the voltage up. The Jab factory says to check for a bad earth on the yellow reference wire, which could cause spikes to 17v. Is this what causes my problem? The Lithium shop said not; the Lipo battery's internal circuitry would not disconnect it from the system. If not, what is cutting the power? Several sources claim these batteries are compatible with automotive/aviation alternator charging systems. ...automatic over-voltage circuit protection is recommended for your charging system. This is an important backup safety feature to protect the aircraft electrical system from high voltage events (typically > 16V What I need: My battery has 16 cells in groups of four and charging should be limited to 14.5v max. So this is my problem: can anyone recommend a unit can that will do this?
  10. That usually works, Nev, but in this case I can't figure out what changed. This configuration worked well for a couple of years, then the problem arose. Dogged experimentation by changing one thing at a time normally works, but if the problem becomes intermittent what then? This morning I blu-tacked a multimeter to the panel, connected it directly to the LiFePO4 battery (to see if its internal circuitry was disconnecting it) and went for a fly. Nothing went wrong. All part of life's rich tapestry.
  11. All nice ideas, Bald Eagle. If implemented, who would consider manufacturing an aero engine? The market is tiny, and now you want to greatly incease the set up costs.
  12. Yesterday's test result didn't seem to very conclusive; I doubt the strange power outage is associated with poor connections, because it happens after a full-power climb and because of the way it resolves itself with wild swings of volts and amps. This morning I repeated the test and the same sequence of power loss, wild fluctuations and recovery repeated itself. Then, as suggested, I installed the old lead battery again and did two full-power climbs to 3,000' and cruised around for half an hour. No power loss. I suspect Jetboy's post is close to the money: "The behaviour you are describing is typical of an overvoltage cutout system operating when it thinks the 20V or 40V spikes put out by the Jabiru dynamo (PMA ) occur , which will be most prominent after the battery has been topped off from the starting and ground idle discharge period. " On the strength of this, and following advice from Flyboy, I plan to replace the regulator/rectifier. As with Methuselah, I'd like to install a Powermate, but that business hasn't replied to my email. Does anyone have a contact number for them?
  13. Flying Doctor by Clyde Fenton is remembered by my daughter as one of the funniest books w shared.
  14. I thought Ian’s site had every possible topic covered, but can’t find a section about good flying books. I’ve read a few and just finished one about the first man on the moon. I hadn’t realised how much flying skill these pioneering astronauts and cosmonauts needed. Most of them had mobs if experience as test pilots and in military combat. Before he got involved in the space program, Neil Armstrong flew everything from jet fighters to B-29s. Many times he flew the X-15 almost into space, and was a highly-qualified aeronautical engineer. One of his greatest inspirations: Konstantin Tsiolkovski, the visionary Russian rocket pioneer. One thing I got from this book was an appreciation of how space exploration is vital for our long-term survival. Even if we finaliy wake up to ourselves and start taking better care of our little planet, we can’t live here forever. Eventually it will get clobbered by a big rock and we’ll be exterminated. Lets hope that by then we have viable colonies on other planets... NEIL ARMSTRONG A life of flight by Jay Barbree
×