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rlborger(at)mac.com
Guest

Posted: Tue Oct 08, 2013 12:32 pm Post subject: Battery questions

Raimo,



I too have been known, on a rare occasion, to leave the master on.  I think I've done that three times in the last 5 years.  First two times it was with an Odyssey 680.  First time it happened I put a charger on it and it came back like new.  About 18 months later I did it again.  Put the charger on it and it came back.  But this time I was concerned so I replaced it with a new Odyssey and put the old Odyssey in an old Jeep we use at the hunting lease.  It worked in that Jeep for about 4 years till my hunting bud left the key on for about 6 months.  That pretty much killed it.  Meanwhile, this spring, I replaced the Odyssey in the Europa with a tiny little, very light (and very expensive) LiFePo battery.  The Odyssey I took out went into the Jeep.  The new LiFePo battery seemed to work quite well for starting and running.  Eventually, I did a run-down test to see how long it would operate the EFIS, EIS, Radio & Xponder.  Turned out, not very long.  After about 10 minutes things started dropping off.  I recharged & balanced the LiFePo battery overnight and it was fine the next day.  BTW, I kept the charger/balancer on whenever the aircraft was in the hanger.  Flew a couple times over the next week and parked it to do more testing.  This time I went off leaving the master on (with the charger attached, btw).  Next day, the battery was DEAD.  And I mean DEAD.  Would not accept a charge.  I put a new Odyssey back in the aircraft and plan to stick with them from now on.

 

Blue skies & tailwinds,

Bob Borger

Europa XS Tri, Rotax 914, Airmaster C/S Prop.

Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP

3705 Lynchburg Dr.

Corinth, TX  76208-5331

Cel: 817-992-1117

rlborger(at)mac.com



On Oct 8, 2013, at 2:32 PM, Raimo Toivio <raimo.toivio(at)rwm.fi> wrote:






I have a little Odyssey story:



once I forgot my IBBS (Integrated Battery Backup System) on for several weeks, which gives juice to my Gemini ADI (Tru Trak). It went empty and so went finally my lovely Odyssey. Normally there is like fixed 12,58 V but now hardly 4 V (four). I had a must to fly so I elected to fire upp engine w an external battery. I run the engine say 20 minutes and after that session it was fireable by Odyssey only. I never noticed any failures in that brave battery but just in case I ordered a new one (Odyssey retail shop is just 10 km from here). Now I have a reserve battery, which is year modell 2006, has been in use 6 years, went totally empty and still a new like. So far I will carry those extra kilos happily - want to hear more reports before updating more modern batt techs.



Cheers, Raimo

OH-XRT



My wife was licensed on Monday with w top ratings. Now I know how is it to try to sleep w a captain.

raimo.toivio(at)rwm.fi
Guest

Posted: Tue Oct 08, 2013 9:25 pm Post subject: Battery questions

WoW Bob,



that was a story which was expected.



If somebody has an obsession to update for a 

LiFePo style battery, I would carry always omboard 

a spare one (or have a dual system and not forget 

a 2nd master on).



10 minutes is an awful short time to have 

electricitet in the case alt/chg failure - that is 

an another reason to have a dual system (if you 

are a LiFePo - user boy).



Cheers, Raimo



-----Alkuperäinen viesti----- 

From: Robert Borger

Sent: Tuesday, October 08, 2013 11:31 PM

To: europa-list(at)matronics.com

Subject: Re: Re: Battery questions




<rlborger(at)mac.com>



Raimo,



I too have been known, on a rare occasion, to 

leave the master on.  I think I've done that three 

times in the last 5 years.  First two times it was 

with an Odyssey 680.  First time it happened I put 

a charger on it and it came back like new.  About 

18 months later I did it again.  Put the charger 

on it and it came back.  But this time I was 

concerned so I replaced it with a new Odyssey and 

put the old Odyssey in an old Jeep we use at the 

hunting lease.  It worked in that Jeep for about 4 

years till my hunting bud left the key on for 

about 6 months.  That pretty much killed it. 

Meanwhile, this spring, I replaced the Odyssey in 

the Europa with a tiny little, very light (and 

very expensive) LiFePo battery.  The Odyssey I 

took out went into the Jeep.  The new LiFePo 

battery seemed to work quite well for starting and 

running.  Eventually, I did a run-down test to see 

how long it would operate the EFIS, EIS, Radio & 

Xponder.  Turned out, not very long.  After about 

10 minutes thi!

ngs started dropping off.  I recharged & balanced 

the LiFePo battery overnight and it was fine the 

next day.  BTW, I kept the charger/balancer on 

whenever the aircraft was in the hanger.  Flew a 

couple times over the next week and parked it to 

do more testing.  This time I went off leaving the 

master on (with the charger attached, btw).  Next 

day, the battery was DEAD.  And I mean DEAD. 

Would not accept a charge.  I put a new Odyssey 

back in the aircraft and plan to stick with them 

from now on.



Blue skies & tailwinds,

Bob Borger

Europa XS Tri, Rotax 914, Airmaster C/S Prop.

Little Toot Sport Biplane, Lycoming Thunderbolt 

AEIO-320 EXP

3705 Lynchburg Dr.

Corinth, TX  76208-5331

Cel: 817-992-1117

rlborger(at)mac.com



On Oct 8, 2013, at 2:32 PM, Raimo Toivio 

<raimo.toivio(at)rwm.fi> wrote:




<raimo.toivio(at)rwm.fi>



I have a little Odyssey story:



once I forgot my IBBS (Integrated Battery Backup 

System) on for several weeks, which gives juice to 

my Gemini ADI (Tru Trak). It went empty and so 

went finally my lovely Odyssey. Normally there is 

like fixed 12,58 V but now hardly 4 V (four). I 

had a must to fly so I elected to fire upp engine 

w an external battery. I run the engine say 20 

minutes and after that session it was fireable by 

Odyssey only. I never noticed any failures in that 

brave battery but just in case I ordered a new one 

(Odyssey retail shop is just 10 km from here). Now 

I have a reserve battery, which is year modell 

2006, has been in use 6 years, went totally empty 

and still a new like. So far I will carry those 

extra kilos happily - want to hear more reports 

before updating more modern batt techs.



Cheers, Raimo

OH-XRT



My wife was licensed on Monday with w top ratings. 

Now I know how is it to try to sleep w a captain.



browse

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Fred Klein

Joined: 26 Mar 2012
Posts: 503

Posted: Wed Oct 09, 2013 7:55 am Post subject: Battery questions

On Oct 8, 2013, at 10:25 PM, Raimo Toivio wrote:

 	  Quote: 	
		  If somebody has an obsession to update for a LiFePo style battery, I would carry always omboard a spare one (or have a dual system and not forget a 2nd master on).



10 minutes is an awful short time to have electricitet in the case alt/chg failure - that is an another reason to have a dual system (if you are a LiFePo - user boy).

	




Once again we find that "there's no free lunch"...

do not archive



 [quote][b]

Alan Carter

Joined: 02 Jul 2012
Posts: 378
Location: Kent, England.

Posted: Wed Oct 09, 2013 2:17 pm Post subject: Re: Battery questions

Hi All.

I just have one Odyssey haven't a clue as to the size of it, also a 914,

But to me it seems crazy to rely totally on electrics for fuel supply.

If the fuel stops the engine stops.

Why hasn't the 914 a mechanical pump, as well as an electrical pump. What's the reason not have a mechanical pump in the system, the 912 have both. 

Its the same as having a totally electric instrument panel, I much prefer

a dual system. Systems do fail and usually its the time when you really didn't want it too.

Alan

rlborger(at)mac.com
Guest

Posted: Wed Oct 09, 2013 6:02 pm Post subject: Battery questions

Hi Alan,



The 914 requires higher pressure in the fuel bowl than the 912 due to the turbo.  The Rotax fuel pump can not supply sufficient pressure to force fuel into the bowl.  The Rotax stock method of supplying the fuel is to use two electric fuel pumps.  Either of which is capable of feeding the engine.  One to be powered from the main buss the other to be powered from the battery.  So should the main generator drop off, the second pump will be fed directly from the the battery giving you time to get the aircraft safely on the ground.



Personally, I didn't like the arrangement either.  I installed an engine driven fuel pump from Billet ( billetpump.com & http://www.billetpump.com/home2/pumps.html ).  Not cheap, but it sure does work.  And my engine is no longer electrically dependent.  Obtaining a pump from them can be a trial.  A couple years ago I tried to buy several pumps for folks in Switzerland and France and gave up after 18 months of trying.  Kind of crazy company to deal with but they produce excellent products if you can ever get one. 



I'd be happy to try them again should you or anyone else wish to acquire one of the pumps.



If you go to http://www.europaowners.org/main.php?g2_itemId=78854 you can see my pump and the work I went to for installation.  I believe that they have refined the pump since then and installation can be much easier.



Blue skies & tailwinds,

Bob Borger

Europa XS Tri, Rotax 914, Airmaster C/S Prop.

Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP

3705 Lynchburg Dr.

Corinth, TX  76208-5331

Cel: 817-992-1117

rlborger(at)mac.com



On Oct 9, 2013, at 5:17 PM, Alan Carter <alancarteresq(at)onetel.net> wrote:






Hi All.

I just have one Odyssey haven't a clue as to the size of it, also a 914,

But to me it seems crazy to rely totally on electrics for fuel supply.

If the fuel stops the engine stops.

Why hasn't the 914 a mechanical pump, as well as an electrical pump. What's the reason not have a mechanical pump in the system, the 912 have both. 

Its the same as having a totally electric instrument panel, I much prefer

a dual system. Systems do fail and usually its the time when you really didn't want it too.

Alan

davidjoyce(at)doctors.org
Guest

Posted: Thu Oct 10, 2013 12:08 am Post subject: Battery questions

Alan, you have in effect got a dual supply - the battery 

and the alternator. If you have wired things according to 

the Europa instructions you will find that you can switch 

off both main & alternator switches in flight and the 

engine keeps running. All the electrical instruments which 

haven't got internal batteries go out, which is a bit 

scary but the engine remains entirely happy, fuelled by 

the electric pump run directly off the alternator.

Regards, David Joyce, G-XSDJ (914 mono)



On Wed,  9 Oct 2013 15:17:13 -0700

  "Alan Carter" <alancarteresq(at)onetel.net> wrote:

 	  Quote: 	
		   

<alancarteresq(at)onetel.net>

 

 Hi All.

 I just have one Odyssey haven't a clue as to the size of 

it, also a 914,

 But to me it seems crazy to rely totally on electrics 

for fuel supply.

 If the fuel stops the engine stops.

 Why hasn't the 914 a mechanical pump, as well as an 

electrical pump. What's the reason not have a mechanical 

pump in the system, the 912 have both. 

 Its the same as having a totally electric instrument 

panel, I much prefer

 a dual system. Systems do fail and usually its the time 

when you really didn't want it too.

 Alan

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=410164#410164

 

 

 

 

 

 

 

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Forums!

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frans(at)privatepilots.nl
Guest

Posted: Thu Oct 10, 2013 1:21 am Post subject: Battery questions

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Hash: SHA1



On 10/10/2013 12:17 AM, Alan Carter wrote:



 	  Quote: 	
		   Why hasn't the 914 a mechanical pump, as well as an electrical

 pump. What's the reason not have a mechanical pump in the system,

 the 912 have both.


	


There are two reasons:

1) The 914 needs a higher fuel pressure.

2) The 914 runs hotter, and the inlet air has an elevated temperature

because of the compression by the turbo. A mechanical fuel pump

connected to the hot engine, plus its long hose routing through the

cowling, allows considerable heat transfer to the fuel. Then you have

the combination of hot inlet air and hot fuel. This increases the

chances of vapor lock (and detonation?) considerably. The Rotax

engineers designed the fuel system of the 914 setup such that you can

keep the fuel pumps outside the cowling, with no mechanical connection

to the hot engine, and with very little fuel hose exposed inside the

cowling. Together with the high return flow this ensures that the fuel

reaching the carbs won't get too hot.



The concept works, I don't remember having seen reports of a double

electrical fuel pump failure. Don't fix something that isn't broken!



If you want additional redundancy, I would recommend putting an extra

alternator on the engine. There are very small light weight

alternators that fit on the vaccuum pad of the engine and are able to

run a fuel pump plus some additional items. You can only use it of

course if you have no vacuum pump on the engine.



Frans



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JonathanMilbank

Joined: 14 Apr 2012
Posts: 395
Location: Aberdeen area

Posted: Thu Oct 10, 2013 5:40 am Post subject: Re: Battery questions

My situation: this winter I'm upgrading from Rotax 912UL to 912S 100hp, but keeping the installation in the Classic engine bearer and retaining the original cowlings and firewall forward as far as possible. Therefore I MUST keep the old shorter starter motor.



For C of G reasons, the battery must be mounted in the rear fuselage behind the old (smaller) baggage bay and therefore the battery must be very safe and immune from risks of overheating. At the moment I have a simple ride-on lawnmower lead-acid battery, which might not have enough "oomph" to start the higher compression S engine.



What I'm hoping you can tell me is which is the most common battery used in UK LAA Permit Europas and referring to a friend's quote "I can't remember what the system voltage is with the engine running, but the odysseys need 14.1 to 14.7v to ensure avoidance of both sulphation and overcharging", should I be installing a different rectifier/regulator?



My 912UL engine only produces a maximum of 14.2 volts. Maybe I can manage with the ride-on lawnmower battery, but I doubt it.

paul.the.aviator(at)gmail
Guest

Posted: Thu Oct 10, 2013 9:13 am Post subject: Battery questions

Okay, I'll weigh in. I am with Frans on this one. 

There are various strategies to overcome the risk of electrical dependency. I am using Bob Knuckles single battery E buss system and I can confirm that this works.  

My Europa took a lightning hit which took out my main electrical system and I was able to switch over to the E buss and continue flying to the nearest airport. This system (if maintained) allows me to fly for over 90 minutes.  

There are refined, well understood designs for single battery E buss, single battery dual alternator, or dual battery dual alternator systems.

Redesigning the Rotax fuel delivery system isn't what I would choose to do.

Just my 2 cents worth.

[quote]  

 On 10/10/2013 12:17 AM, Alan Carter wrote:

 > Why hasn't the 914 a mechanical pump, as well as an electrical

 > pump. What's the reason not have a mechanical pump in the system,

 > the 912 have both.

The Rotax

 engineers designed the fuel system of the 914 setup such that you can

 keep the fuel pumps outside the cowling, with no mechanical connection

 to the hot engine, and with very little fuel hose exposed inside the

 cowling. Together with the high return flow this ensures that the fuel

 reaching the carbs won't get too hot.

 The concept works, I don't remember having seen reports of a double

 electrical fuel pump failure. Don't fix something that isn't broken!

 Frans

[b]

clivesutton

Joined: 23 Jan 2013
Posts: 187
Location: KENILWORTH

Posted: Thu Oct 10, 2013 9:40 am Post subject: Re: Battery questions

"My Europa took a lightning hit"



wow - that's a story - was there any structural damage or signs of plasma entry/exit?  Any pictures?  I have always thought a lightning strike would incapacitate a Europa airframe



Do tell

Clive

Fred Klein

Joined: 26 Mar 2012
Posts: 503

Posted: Thu Oct 10, 2013 9:42 am Post subject: Battery questions

On Oct 10, 2013, at 10:12 AM, Paul McAllister wrote:

 	  Quote: 	
		  There are various strategies to overcome the risk of electrical dependency. I am using Bob Knuckles single battery E buss system and I can confirm that this works.  

	




Paul,

Can you recall which of the "Z" circuit diagrams you used as a guide?

Fred

 [quote][b]

paul.the.aviator(at)gmail
Guest

Posted: Thu Oct 10, 2013 10:40 am Post subject: Battery questions

Sorry Fred, 



Its nearly 10 years since I wired up my airplane. I'd suggest to sign up to Bob's forum and put the question out there.

Paul



 



On Thu, Oct 10, 2013 at 12:41 PM, Fred Klein <fklein(at)orcasonline.com (fklein(at)orcasonline.com)> wrote:

[quote] 

On Oct 10, 2013, at 10:12 AM, Paul McAllister wrote:



 	  Quote: 	
		   There are various strategies to overcome the risk of electrical dependency. I am using Bob Knuckles single battery E buss system and I can confirm that this works.  

	


Paul,

 



Can you recall which of the "Z" circuit diagrams you used as a guide?

Fred

  	  Quote: 	
		  



arget="_blank">http://www.matronics.com/Navigator?Europa-List

tp://forums.matronics.com

_blank">http://www.matronics.com/contribution



	




[b]

Alan Carter

Joined: 02 Jul 2012
Posts: 378
Location: Kent, England.

Posted: Thu Oct 10, 2013 12:33 pm Post subject: Re: Battery questions

Hi Bob ,David and All.

Many thanks for your reply's, it must have been a good question.

Very interesting on the Alternator wiring and the Battery, I will check it out,

but not in the air David, I did not build the plane, I have learnt something here and will post what I find,

Lots of Alternators and spare Battery's required, I much prefer Bobs mechanical pump and if well insulated should have no heat problem.

All these other options are work arounds and I have no doubt they all work but one should not have to do all these work arounds and if one buys a Â£30000 engine it should not be totally dependant on electricity, the pumps may be OK but if the Alternator fails and lets say an old battery or loose terminal the engine stops, This does not sound good design to me.

If you have a Vacuum drive generator I take it you have no Vacuum instrument ??,so down to electric only. 

I will make do with what I have, just hope its wired Alternator pump, battery pump, so does mean that if the engine is not running my Number 2 pump will not run as I prim using the number on pump.

Many thanks.

Alan

pete(at)lawless.info
Guest

Posted: Thu Oct 10, 2013 1:14 pm Post subject: Battery questions

Hi All



Just a question for the all electric pumps installation - you are flying

happily along when that burning insulation smell starts followed by smoke

seemingly from behind the panel - what do you turn off?



Personally I would just like to kill all the electrics and still have my

engine running.



Pete



G-RMAC Classic 912ul



PS OK so it has not happened yet but that does not mean it won't!



--

brian.davies(at)clara.co.
Guest

Posted: Fri Oct 11, 2013 12:16 am Post subject: Battery questions

Jonathan,



I have been using a Varley Redtop 25 racing battery which is 16AH AGM

(absorbed glass matt).  This is virtually identical spec to the Odyssey

PC680 which many people use for a Rotax 912S.  It has provided perfect

starting for 6 years.  The battery is behind the baggage bay and uses 4

gauge battery cables. I have never seen more than 14.2 volts system voltage

and on a fully charged battery it is mostly at 13.8 volts.



Provided you have good connections and big enough cable, I don't think you

will have any problems with a new Rotax 912S, even with the older starter,

as long as the sprag clutch is in good condition.



Regards



Brian Davies



--

frans(at)privatepilots.nl
Guest

Posted: Fri Oct 11, 2013 1:56 am Post subject: Battery questions

-----BEGIN PGP SIGNED MESSAGE-----

Hash: SHA1



On 10/10/2013 11:14 PM, Pete Lawless wrote:



 	  Quote: 	
		   Just a question for the all electric pumps installation - you are

 flying happily along when that burning insulation smell starts

 followed by smoke seemingly from behind the panel - what do you

 turn off?


	


First of all, it should not be possible that this happens. There is a

simple rule, always wire downstream of a CB or fuse with a wire gauge

suitable for carrying at least the max current of the CB or fuse. So,

even if something goes wrong, then still either the CB pops or nothing

happens.



Secondly, invest in a good amps gauge. I know from all equipment how

much current it is normally using; if something goes wrong I can

easily sort out which circuit is going south and pull the assosiated

CB. If there is smoke, there must be quite some current flowing

somewhere, and it should be relatively easy to find the corresponding

circuit.



Third, if you follow the Europa design you have the second fuel pump

wired directly to the alternator. This means that you can indeed turn

off everything and the engine keeps running. Unless the fault is in

the alternator or remaining pump, but then this means that the rest of

the system is still alive so you should be able to operate from the

other fuel pump. Of course this is only possible if there is a way to

isolate the alternator from the electrical system, either manually or

with a CB/fuse.



Last, I have two completely independant electrical systems, each with

its own alternator and battery. I can kill one complete electrical

system and operate the ship from the remaining bus.



 	  Quote: 	
		   Personally I would just like to kill all the electrics and still

 have my engine running.


	


That is still possible.



Frans

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Alan Carter

Joined: 02 Jul 2012
Posts: 378
Location: Kent, England.

Posted: Fri Oct 11, 2013 2:09 am Post subject: Re: Battery questions

That, what I would do Peter, Kill the lot, then pull all the breakers, and if I found I really needed something turn that one on. But before I do I must check David's wiring out, With my luck its probably wired wrong, and the engine will stop.

I am wiring my new FFM directly to the battery with fuse and switch, so in the event that If ever i kill the lot, I will still have engine running and fuel indications.

Alan

frans(at)privatepilots.nl
Guest

Posted: Fri Oct 11, 2013 2:16 am Post subject: Battery questions

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Hash: SHA1



On 10/10/2013 10:33 PM, Alan Carter wrote:



 	  Quote: 	
		   I much prefer Bobs mechanical pump and if well insulated should

 have no heat problem.


	


I'm interested to learn how you are going to thermally insulate a

metal fuel pump bolted to a hot metal engine.



Remember that a hot fuel pump is exactly the place where you can

expect vapor lock and/or cavitating. And where it does the most harm

because the pump then works in a void and the fuel flow stops. There

is a reason why the Rotax engineers strayed off the obvious route and

came up with something else...



 	  Quote: 	
		   and if one buys a ï¿‚ï¾£30000 engine it should not be totally

 dependant on electricity,


	


You'd better get used to it. Fuel injection and fadecs are on the rise

and without doubt will soon every new engine be dependant on

electricity. The advantages far outweigh the disadvantages.



It may have escaped to you that the Rotax alternator has a very

special design. It has no brushes, no moving parts at all that can

fail. It is the very same alternator that produces the electricity for

the spark plugs. In fact, also the 912 is completely dependant on the

very same alternator; without it the spark plugs won't fire and also

the 912 won't fly any further. So, even if you have a mechanical fuel

pump you still have a complete engine stop if this alternator fails.

Luckily, it is quite unbreakable.



 	  Quote: 	
		   the pumps may be OK but if the Alternator fails


	


If the alternator fails the spark plugs won't fire anymore, so it

doesn't matter whether the pumps stop.



 	  Quote: 	
		   If you have a Vacuum drive generator I take it you have no Vacuum

 instrument ??


	


Vacuum pumps suck. I hope you are not suggesting that vaccuum is more

reliable than electricity?



Frans



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frans(at)privatepilots.nl
Guest

Posted: Fri Oct 11, 2013 2:24 am Post subject: Battery questions

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On 10/11/2013 12:09 PM, Alan Carter wrote:



 	  Quote: 	
		   I am wiring my new FFM directly to the battery with fuse and

 switch, so in the event that If ever i kill the lot, I will still

 have engine running and fuel indications.


	


What's wrong with wiring the fuel pump to the alternator?



If you wire it to the battery, you are defying the purpose of the

master switch. In a crash landing, I wouldn't care whether the spark

that ignites my leaking fuel was coming from my GPS or from my fuel

indicators or fuel pump. (Not to mention the fact that the fuel pump

may continue to run after the crash, something you might not desire if

there is a fuel leak upstreams).

If you wire to the alternator, nothing can go wrong, assuming that the

engine will stop at impact and the electricity is long gone before you

come to a stop.



I must say that I'm a bit surprised how many people easily modify the

fuel system and/or electrical system, without understanding what the

reasons were why it was designed in that specific way.



Don't fix something that isn't broken!



Frans



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gilles.thesee(at)free.fr
Guest

Posted: Fri Oct 11, 2013 4:04 am Post subject: Battery questions

Frans Veldman a écrit :

 	  Quote: 	
		  



 I must say that I'm a bit surprised how many people easily modify the

 fuel system and/or electrical system, without understanding what the

 reasons were why it was designed in that specific way.



   

Frans and all,
	




During the build of our project, we made a thorough study of the 

electrical system of the Rotax 914.

We discovered that in some cases true redundancy is not achieved with 

the schematic provided by Rotax, because of  the Rotax voltage regulator 

behavior.

That's why we had to resort to dual battery installation.



Concerning the fire hazard in a crash, it is admitted that skinny hot 

conductors (less than 5 amp) present relatively low risk.

Let's remember that at least one always hot conductor exists between the 

master switch and the main battery contactor, though the current is 

limited by the contactor coil.



Best regards,

-- 

Gilles

http://contrails.free.fr

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