RFguy

NO ground 'circuit'. Ground location - yes. But regulator CANNOT go to the busy ground say on the firewall that a bunch of things front side and back get connected to. The reason for connecting the regulator direct to battery ground (or - the engine block is pretty well battery ground because of the 50mm2 cable to the battery negative) , is that high pulsing current from the regulator needs NOT to crosstalk with other signals. If the alternator regulator negative goes to some 'ground bus' then that whole ground bus will be noisy unless there is another (short) 50mm2 cable to the bat negative. it is no longer ground if you connect the noisy charging current into it. ground is supposed to be quiet.

so in that case, needs a shaft through the firewall to the battery isolator location. Yes, I do like that !

Nev, pls expain the 'crash bar' comment ? Do you mean some sort of method to short the bus and blow the battery fuse ?

SAFE JABIRU - WITH BATTERY ISOLATION - METHOD 2 - ROUTING STARTER CURRENT AROUND MAIN ISOLATOR (AND THUS CAN USE SAME 40 AMPS RELAY AS ALTERNATOR )

SAFE JABIRU - WITH BATTERY ISOLATION - METHOD 1 - ROUTING STARTER CURRENT THROUGH MAIN BATTERY ISOLATOR \

V1.1

Good. 5A fuse for the sense wire OK. The wire will pass 5A and blow the fuse if there is a fault. (remember- idea is that fuse blows before wire melts) In your photo, the starter V+ goes to the starter solenoid ..... I see a smaller red wire going to the battery V+ terminal to a connector off photo - I gather this is the regulator charge output (check). this needs to have a 20A fuse in it so that if the regulator fails it doesnt cause a fire. There needs to be THE alternator charger relay that we discussed in series with this 20A fuse. The alternator relay can have the negative of the coil to ground (anywhere) and the positive of the relay coil should go back through the firewall to your MASTER 12V bus. That is the minimum for modifications And regulator sense wire to battery termal. If you want to go further, you can see that there are UNFUSED battery white wires going through the firewall. This is bad in an crash- the battery master relay needs to be IN the engine bay and connected to the master switch. so that unfused and unswitched battery + does NOT go through the firewall ..... There is a master relay behind the instrument panel, that relay needs to be moved next to the battery and via a good sized fuse probably 30A is enough for a Jabiru.

Jabiru company aircraft wiring is... questionable. Battery sense should ALWAYS go to the battery (via small fuse) NO MATTER WHAT. anyone who wants an argument, put $10,000 on the table and let's have a bet. Comon, I'll see you in court. Battery charge should go to the battery to remove alternator 'noise' components from the wiring harness. If the battery charge wire goes to the harness/master, then high frequnecy battery charge current 'noise' will fill and pollute the 12V bus . Battery charge must go via a fuse (20A in this case) AND ideally, via an isolation relay that is actuated from the master 12V bus. Battery negative SHOULD go to the negative battery terminal BUT engine block is good enough because starter cable size, direct to battery negative, is usually sufficiently sized to not have any voltage -current noise. Jabiru factory wiring practice I beleive, may be responsible for Jabiru airframe fires. IE the need of a master battery contactor - because std Jab wiring puts UNFUSED battery B+ through the firewall. Where as good practice, and safe practice, and certainly all part91 cert aircraft, the battery is isolated at the battery via a contactor/relay which is turned on and off via a battery master switch. This has been well covered by me here several times.

Hi Jenny well, if the 'avionics guy' didnt connect the battery sense wire, he either was having a bad day, or needs to be sued, or the wire 'came off'. So, I am sure there is more to this story. ANyway, get what I suggested done. If the headlamp relay doesnt have a 'flyback/reverse' diode across the coil, ensure that one gets put on. No-----, if you fly with high voltage like that (The TRUE peak voltage is much higher than indicated) you'll damage everything connected to the 12V bus..... If not damaged now, you will reduce the life and things will die for no reason prematurely, even after it is all fixed up.... Use something like a : - they have the diode in them. NARVA 68032 or 68032BL NOTE THAT THESE UNLESS MOST RELAYS WILL HAVE + AND - ON COIL . - to ground, + to 12V bus so relay turns on when master on Repco Australia | Auto Parts Store - Aftermarket Car Parts WWW.REPCO.COM.AU Narva | 12V 40A NORMALLY OPEN 5 PIN RELAY WITH DIODE (BLISTER PACK OF 1) WWW.NARVA.COM.AU Narva relays are manufactured to exacting original equipment standards under the control of ISO9001. or Narva | 12V 40A NORMALLY OPEN 5 PIN RELAY WITH DIODE WWW.NARVA.COM.AU Narva relays are manufactured to exacting original equipment standards under the control of ISO9001. NARVA 68032 or 68032BL

yes indeed, the regulator has no voltage sense so it just thinks the battery is flat all the time voltage sense wire must be connected. WHo did this work prior to you ???? Needs all the wires for the regulator connected. Jabiru's wiring is a bit F-ed up anyway, but it can be acceptable. DO NOT fly or run it over 1500 RPM with the regulator like that- you will damage ALL of your electrical systems and electronic instruments.... Regulator negative should go to the engine block which has a really good solid negative wire connection to the battery via the starter cables. Regulator sense wire (usually yellow) needs to go to the battery via a 1 amp blade fuse. Regulator charge output needs to go direct to the battery via a 20A blade fuse . There will be a tiny bit of current always drawn so it might flatten the battery over a couple of months. IDEALLY an extra relay (small cube headlamp relay will do it) is required from the master , the relay goes in series with the alternator charge output so when the master turns off, the regulator charge output is disconnected from the battery. and....Transient voltage suppressors or diodes need to be across the main bus to avoid the master relay back EMF damaging radios and electronics, as it does....

how good is the ADSB coverage in the region at ground level- is this the termination of flight, or just the ADSB coverage limitation ? glen

My Samsung A8 tablet internal GPS works fine, providing the orientation is in portrait mode up. (this is important !!!!). do not need internet en route. allow 10 minutes to get GPS though.

Looks fantastic. I did 'airwork'. practiced flapless approaches, glides etc. It took 4 goes for me to make the glide approach work.... in nil wind. tut. tut. needed the practice after flying many 400nm A to B flights.... I even got carb ice ! (during startup/ runups) .

that's my guess, also. Plane bound for Armidale from Canberra would have been full of fuel...

Oz runways is as complicated as you want, or as simple as you want. Good for flight planning, and handy to have a tablet around for various pre flight tasks. ATM, I just use it as a fancy moving map GPS box , and to display other traffic via Skyecho. In fact, that's probably its primary use because the common 300-400nm routes I fly I don't need a map or a GPS... Load up every map /download when you get it. It doesnt use much memory of a modern tablet. Set up for download overnight / manual data download so it doesnt chew up data when you are using it. LIS, I have a WIFI version, and hotspot my phone to the tablet when it needs internet- usually preflight/planning.

I'd be pretty sure the DCDC converter is making some of the noise there is also right and wrong ways to use the ferrite clamps- they must be on the antenna coax cable at both near antenna end, and at the radio end just where it exits the instrument panel. and you might need 4 to 6 in a row. Then Find the DCDC converter and put perhaps 6 ferrite clamps on input and output, but if its radiating directly from the device, that wont do anything. It will have a DCDC converter in there, because the 14.4V constant voltage perfectly describes it being there.... The total noise - It could be the sum of many things.

OK, is a lead acid battery, not any sort of ltihium battery ? anyway, the DCDC converter needs to be found and removed (it will run avionics so it wil need ot be bypassed) Be sure to look in the log maintenance books to find out WHY it was installed, is a good idea first. But it is absolutely NOT required.

Pretty sure you have a DCDC converter in there, that does not need to be in there... could be some of the trouble, Highly unusual to have the voltage fixed like that, if the voltage aint varying, you have a DCDC conv in there and it should be removed, the system does NOT need it. Where did this aircraft come from ? IE non direct from factory I guess

Mike said - "Have you worked through this section of the Jabiru manual 'Radio Frequency (RF) Noise Reduction'?" footnote- I dont think that's useful at this point, but a good point for folk without access to me.

AND.... further more- where is your voltage monitor source from- that sounds like it is connected to a DCDC converter somewhere !!! The DCDC converter will usually take varying voltage and convert to a constant voltage. I smell a rat !! I smell a noisy DCDC converter rat !!

1000 rpm 14.4 is suspect high. a Jabiru does not charge below 1200-1500 RPM. I would expect < 13.2 unless it has been on charge. A rat is smelt. With all avionics on and 1000 RPM, I would expect < 13.5. New engine- remind me , what engine ? what sort of battery ??? Was 14.4 with avionics on , landing light on ? Doesnt seem usual behaviour,

and when you say , new regulator- new since new radio ?

A few good ideas by others, but Jabiru engines norrmally dont have too many problems.... hence I'm looking for a fault, or something specific to your installation. A DC DC convertor is not a noise suppressor. DCDC converters are more are noise generators... I do not think your problem has anything to do with the 12V bus noise UNLESS you have a sick alternator regulator... (which I have seen and do the same thing) Still need this info : WHAT is the 12V bus voltage at 1000RPM, 1500 , 2000, and 2300RPM ????

and a fire in a composite plane is no good... I'm surprised if a well maintained aircraft would catch fire in flight. (not really saying much, I think we'd all be surprised if our aircraft caught fire). The 120 kts to the ground though isnt all that fast in controlled flight for that aircraft . So I dunno about a fire.....would have though pilot would adopt the inflight fire suggestion in the POH. (which is get down as fast as possible) . So I am discounting a fire in probability. and that the aircraft looks like it was in one piece when it 'landed' vertically.