danny_galaga Posted June 12 Share Posted June 12 Sorry, I should have said stator, not field. My point is that regulating the output instead of the input is no big deal when it's only say 20 amps at most. You forgot to mention that the regulator is doing those steps many times a second. When described in steps people may not realise it. It's a fairly smooth operation from our point of view. I admit I know nothing of how it affects anything other than a lead acid battery. Those are pretty forgiving. Just pointing out that for general purposes they work just as well as regulating a rotor (which as you point out is actually the field winding, permanent magnets being the alternative to an electrically created field) 3 Link to comment Share on other sites More sharing options...
RFguy Posted June 12 Share Posted June 12 hundreds of times per second. each time there is a stator pole pulse . Usually an electronic component called an SCR is used which gets turned on by the regulator, and turns off by itself at the end of the pole pulse. 3 Link to comment Share on other sites More sharing options...
facthunter Posted June 12 Share Posted June 12 THAT would have to create electrical noise, surely,. Permanent magnets can lose some of their magnetism also but they are self exciting and others relying on residual magnetism may not start if the Battery is discharged. The switch is often start Off Run. Nev 1 Link to comment Share on other sites More sharing options...
RFguy Posted June 12 Share Posted June 12 usually with the simple ones, the SCR turns on at start of half cycle, and turns off at the end of the half cycle. no noise. If it turned off or on during the cycle, IE when there was voltage there, that would create noise because of the instantaneous step current. 1 Link to comment Share on other sites More sharing options...
Freizeitpilot Posted June 12 Share Posted June 12 Silent Hektik regulators get a mention on a European ULM forum. I know less than zero on this subject, but just thought I’d mention it in case it is remotely useful to someone here. I note they have a presence in Australia. https://hektikgroup.com.au/ 1 Link to comment Share on other sites More sharing options...
pluessy Posted June 12 Share Posted June 12 2 hours ago, Freizeitpilot said: Silent Hektik regulators get a mention on a European ULM forum. I know less than zero on this subject, but just thought I’d mention it in case it is remotely useful to someone here. I note they have a presence in Australia. https://hektikgroup.com.au/ I think you got the wrong company, no regulators in their offering? Link to comment Share on other sites More sharing options...
BrendAn Posted June 12 Author Share Posted June 12 6 minutes ago, pluessy said: I think you got the wrong company, no regulators in their offering? You might want to look at skippys post on the prev page Link to comment Share on other sites More sharing options...
skippydiesel Posted June 14 Share Posted June 14 On 12/06/2024 at 7:31 PM, BrendAn said: You might want to look at skippys post on the prev page https://www.silent-hektik.de/UL_R_912.htm Link to comment Share on other sites More sharing options...
Moneybox Posted Thursday at 08:50 PM Share Posted Thursday at 08:50 PM I just wrote this on my iPad and it disappeared when I posted it so I'll try again using the laptop. I just wanted to post my opinion of LiFePO4 batteries. I replaced our 4x120ah eight year old Rittar AGM batteries with 2x100ah Solar King lithium batteries. The AGM batteries took eight years of severe abuse with poor recharging and too many discharges beyond their recommended limit. The AGM batteries were utterly reliable and gave me the security of being a backup for emergency starting if the start batteries failed. They performed admirably with their only drawback being the 100kg weight penalty. The lithium batteries are extremely light weight and hold their voltage well until they reach that critical point of discharge when the battery management system will disconnect them without warning. They will not come back to life until all current drawing devices are disconnected or turned off. I have used them ONCE for an emergency start. They gave me perhaps one second of start power before disconnecting but that was enough to crank the 4.8L Isuzu to start. It took me the next half hour to get the lithium batteries back on line. Any small hiccup in the electrical circuit will cause the lithium batteries to spit the dummy and then there's always a delay getting them back. These lithium batteries are the most unreliable power source I've ever experienced and I wouldn't want to have my life depending on them. 2 Link to comment Share on other sites More sharing options...
Freizeitpilot Posted Thursday at 09:21 PM Share Posted Thursday at 09:21 PM I note that Rotax is now re-branding and selling EarthX LiPo4 batteries. 2 Link to comment Share on other sites More sharing options...
RFguy Posted Thursday at 10:35 PM Share Posted Thursday at 10:35 PM the problem with those batteries is some of them can disconnect themselves ... that is bad for electronics both lack of power supply, and consequent high voltages and nasties that will occur with the perm mag alternator driving no battery Rotax have shown poor engineering judgement (lack of capability, understand, experience and knowhow) 2 Link to comment Share on other sites More sharing options...
Freizeitpilot Posted Thursday at 10:53 PM Share Posted Thursday at 10:53 PM The marketing spiel that comes with them is…… ”come with a battery management system that includes over-discharge protection, redundant charge and discharge circuits, local LED battery fault indicator and remote battery monitoring connection via EFIS or panel mounted LED light “ 2 Link to comment Share on other sites More sharing options...
Freizeitpilot Posted Friday at 01:10 AM Share Posted Friday at 01:10 AM 2 hours ago, Freizeitpilot said: The marketing spiel that comes with them is…… ”come with a battery management system that includes over-discharge protection, redundant charge and discharge circuits, local LED battery fault indicator and remote battery monitoring connection via EFIS or panel mounted LED light “ RFG - how do you interpret this marketing gumpf ? Is this ‘battery management system’ there just to protect the battery, with no downstream consideration to the aircraft electrics / avionics if the battery decides to suddenly ‘protect’ itself ? Interested to hear your thoughts on this. LiPO4 battery technologies clearly have some pros, but good to know the cons as well. Link to comment Share on other sites More sharing options...
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