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Odyssey bat. For RV-10

my RV10

When I bought my RV10 it had a smaller battery that I swapped out and installed the 925. A big improvement.
 
my RV10

When I bought my RV10 it had a smaller battery that I swapped out and installed the 925. A big improvement.
 
I too used 925L for main and 680 for aux. I checked at my local Battery Terminal location first. They did not stock them, but gladly ordered them in for same price as online. I also ordered recommended 12A Odyssey charger after I almost destroyed my 680 from using an auto parts store agm charger. It went to 16.1 V, battery started to swell and lost capacity. After several cycles with new charger it came back to normal capacity. Needless to say, that battery is now in my tug and new one went in plane.
 
Wayne, can you start the engine with the 680? Its cranking amps appear sufficient to crank the 6 cyl. I've put 2 680's in, for a dual bus system, with cross tie, but have not run the engine yet.

thanks,
Bill
 
Another one for 925

I too use the 925 and have gone up to 6 weeks once (I know, bad pilot! I have slapped myself on the wrist) without being able to get out to crank the engine and still had 11.8 volts. The charger is also worth the money. When setting up avionics and calibrating sensors it is easy to hook up the charger, turn the battery on, and get to work and not worry about draining the battery.

Eric
 
Wayne, can you start the engine with the 680? Its cranking amps appear sufficient to crank the 6 cyl. I've put 2 680's in, for a dual bus system, with cross tie, but have not run the engine yet.

thanks,
Bill


Bill,

There are quite a few folks with a pair of 680s. They can start the engine just fine. Some starters are easy than others. I have a pair, but I'm not flying yet. I too have a cross connect if needed, but I think that will be only on the coldest of days. I also upgraded to a Skytec 149NL starter, which I was told requires slightly less amps to crank as well as it has kickback protection compared to the NS that Van's supplies on it's OEM engine.

bob
 
Confused

Okay, now I'm confused. I am right at the point in my tailcone build at which I build the battery tray. Bob, I've seen that you modified your battery tray to carry two batts. Vans seems to think one 680 is enough, as the tray is designed for that. Okay, here are my "dumb questions":
1) I would like a complete IFR panel. Is one 680 battery enough?
2) Will a 925 fit in the standard batt tray, built per the instructions?
3) I read that the 925 can behave as two batteries (whatever that means). If one 680 isn't sufficient, is one 925 enough?
4) Is there an "aftermarket replacement" for the standard Vans batt tray that fits a 925 and/or two batteries, or is a home made modification necessary?
 
I have the faster turning starter without the shear pin which came standard a year ago. Now I think Lycoming may be installing the NL starter due to so many requesting it. I don't have any problem at all with cranking on either battery at 20F and oil preheated to 55F, but I can tell a slight difference in cranking speed between the two batteries. Note: I do have two slick mags, retard terminal on left with slick start module. I have #2 ga copper from rear to starter. I am using engine and airframe as ground path. I sanded paint from six engine mounting locations, then applied alodine and dielectric grease. If one had to crank more than 10-15 seconds in cold wx, I would say the 925L or the two 680's would hold up much better than a single 680. I can run my entire panel on the 680 aux for 1.5 hous safely before things start dropping offline. If aux bat has been run down low, after startup I will recharge main first for about 5-10 min then close crossfeed to charge aux. Otherwise if one tries to recharge the 925L and 680 batteries simultaneously your alt current can exceed 60A limit. The 70A alternator would be nice but not necessary if you monitor things closely.
 
Mike,

I would use 925L if going with one battery as this battery has the desired capacity for our long wire run and IO-540 combination. If you go with two 680's then you will be able to start on a fully charged battery and may be fine unless you have no preheat and temps below 30F. Then you close crossfeed contactor and leave sensitive avionics off for startup. I decided to go with 925L with 680 aux as opposed to just a EFIS backup so that entire panel could be powered up for at least 1.5 hours. The extra weight back there makes it unnecessary to carry any ballast during solo flight. I have BA 2-Blade prop and no air conditioning which gives me plenty of nose weight, so I like having the extra 23-25 lbs back there for w&b. I inst 680 to right and below 925L battery opposite ap pitch servo and sorry no pics.
 
Mike,

I would use 925L if going with one battery as this battery has the desired capacity for our long wire run and IO-540 combination. If you go with two 680's then you will be able to start on a fully charged battery and may be fine unless you have no preheat and temps below 30F. Then you close crossfeed contactor and leave sensitive avionics off for startup. I decided to go with 925L with 680 aux as opposed to just a EFIS backup so that entire panel could be powered up for at least 1.5 hours. The extra weight back there makes it unnecessary to carry any ballast during solo flight. I have BA 2-Blade prop and no air conditioning which gives me plenty of nose weight, so I like having the extra 23-25 lbs back there for w&b. I inst 680 to right and below 925L battery opposite ap pitch servo and sorry no pics.

Thanks Wayne,

I live in Colorado, so I don't plan for, but I do anticipate the need for some cold-starting. I plan also to not install air conditioning, however, I'm thinking I wouldn't mind putting in a little ballast for solo flights, if it means more capacity with adults in the back. Sounds like I'll plan for a single 925L. Does it fit in the standard tray? (i.e. same size but taller than the 680)??
 
Okay, now I'm confused. I am right at the point in my tailcone build at which I build the battery tray. Bob, I've seen that you modified your battery tray to carry two batts. Vans seems to think one 680 is enough, as the tray is designed for that. Okay, here are my "dumb questions":
1) I would like a complete IFR panel. Is one 680 battery enough?

For the panel, yes, but that isn't the question you want to be asking in regards to IFR. The question is if the battery goes away or something takes out the pri alt or battery, what's your plan?

I have two 680s as part of the requirements to minimize risk while flying IFR. I also have two alternators and two independent buses.


2) Will a 925 fit in the standard batt tray, built per the instructions?

Not sure, I have two 680s. They won't. I had to modify the battery tray, but not a big deal.

3) I read that the 925 can behave as two batteries (whatever that means). If one 680 isn't sufficient, is one 925 enough?

Two 680s aren't for starting. It's for other risk mitigation. I can tie both of them for additional cranking power if required. Which should only be needed if you've been in a deep freeze over night.


4) Is there an "aftermarket replacement" for the standard Vans batt tray that fits a 925 and/or two batteries, or is a home made modification necessary?

Not that I'm aware of. It's a pretty simple mod. My build site shows the process that I followed.
 
Yep, 925L fits perfect. You may want to fabricate a 1/2" angle for rear of battery mount as there is about 1" of extra space since the agm type battery was not the original Vans recommended battery.
 
925 fits

Okay, now I'm confused. I am right at the point in my tailcone build at which I build the battery tray. Bob, I've seen that you modified your battery tray to carry two batts. Vans seems to think one 680 is enough, as the tray is designed for that. Okay, here are my "dumb questions":
1) I would like a complete IFR panel. Is one 680 battery enough?
2) Will a 925 fit in the standard batt tray, built per the instructions?
3) I read that the 925 can behave as two batteries (whatever that means). If one 680 isn't sufficient, is one 925 enough?
4) Is there an "aftermarket replacement" for the standard Vans batt tray that fits a 925 and/or two batteries, or is a home made modification necessary?

I have the 925 and it fits in the standard tray just fine. I think (but not sure) that the only time you need to modify the tray is if you will have two batteries. My $0.02.

Oh, and the 925 seems to crank the IO-540 really well. No sluggish cranking even in cold weather. I did get the Odyssey charger and use it whenever I'm sitting in the cockpit working on avionics for more than 10-15 minutes. One more factor: at Sean's suggestion I used the Super-CCA fat cable for both power and ground (http://www.periheliondesign.com/) and I'm sure that helps even more with getting those little electrons from the battery to the starter without running into each other.
 
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dual batteries

Im in process working out details to retro mount battery No2 in the RV10. I need wiring diagram for adding this battery as backup and for cold starts. help is requested. :D Thanks many times, Stokes
 
Im in process working out details to retro mount battery No2 in the RV10. I need wiring diagram for adding this battery as backup and for cold starts. help is requested. :D Thanks many times, Stokes

I don't want to be a stick in the mud, but we don't know enough about your objectives to recommend a solution.

What I can recommend are two sources of information that may have enough information to help you draw some conclusions.

Take a look at Bob Nuckolls' Z-14 design.

I used a VP-X Pro. While Marc doesn't promote a second battery, there are several options documented in the manual. There are two options listed, I actually implemented a hybrid of the two options.

Some questions to think about:

Are you looking just for additional cranking capacity?
Is the second battery the primary power source for an Ebus?
Do you have/need an Ebus?
What about a second alternator?
How will you keep each battery charged?
Failure mode analysis for each component?
 
Bob thank you for your thoughts. I saw on your log how you enlarged the tray and that is what I plan to do also.
I plan the battery for extra cold cranking amps, and stand by for instruments thats all.
No Ebus, just the standard bus per Vans plan and basic circuitry AFS EFIS, trutrak, garmin, xponder, lights, starter etc.
One alternator to charge both batteries and I can see Ill need another relay switch.
I looked at Z14 and I think that will work for me, but Im still not sure of the circuits for #2 to starter and alternator and how to switch #2 into the panel circuit if needed. Im using an idiot light to signal alternator failure, and battery status volts from the EFIS. I want #2 to service the panel only if needed.
Im trying to keep it simple and not add on a bunch of boxes.
Your log is excellent and a joy to browse and thanks for taking so much time to post it. Stokes
 
#2 battery

Bob thank you for your thoughts. I saw on your log how you enlarged the tray and that is what I plan to do also.
I plan the battery for extra cold cranking amps, and stand by for instruments thats all.
No Ebus, just the standard bus per Vans plan and basic circuitry AFS EFIS, trutrak, garmin, xponder, lights, starter etc.
One alternator to charge both batteries and I can see Ill need another relay switch.
I looked at Z14 and I think that will work for me, but Im still not sure of the circuits for #2 to starter and alternator and how to switch #2 into the panel circuit if needed. Im using an idiot light to signal alternator failure, and battery status volts from the EFIS. I want #2 to service the panel only if needed.
Im trying to keep it simple enough for me to understand, :p and not add on a bunch of boxes.
Your log is excellent and a joy to browse and thanks for taking so much time to post it. Stokes
 
My Rocket has a IO540 with the NL starter, and a PC680 starts it just fine. 2 years and it is still going strong.
 
Bob thank you for your thoughts. I saw on your log how you enlarged the tray and that is what I plan to do also.
I plan the battery for extra cold cranking amps, and stand by for instruments thats all.
No Ebus, just the standard bus per Vans plan and basic circuitry AFS EFIS, trutrak, garmin, xponder, lights, starter etc.
One alternator to charge both batteries and I can see Ill need another relay switch.
I looked at Z14 and I think that will work for me, but Im still not sure of the circuits for #2 to starter and alternator and how to switch #2 into the panel circuit if needed. Im using an idiot light to signal alternator failure, and battery status volts from the EFIS. I want #2 to service the panel only if needed.
Im trying to keep it simple enough for me to understand, :p and not add on a bunch of boxes.
Your log is excellent and a joy to browse and thanks for taking so much time to post it. Stokes


Take a look at the manual for the VP-X. There are two options for dual batteries. That solution should give you enough information to tell you what you need know.

bob
 
I bought my RV-10 and it has an Odyssey 1200 installed, a little overkill but cranks right up, even after leaving the master switch on overnight! The downside is it weighs 38.2 pounds so with 4 people and luggage, I am aft cg limited so have to keep minimum fuel for landing. However, no ballast needed when solo:D

I am probably going to get a PC925 or PC680 to swap in for family trips so I can carry more luggage (with my family, currently limited to 65 pounds in baggage compartment with 14 gallons min fuel). Easy way to adjust CG for different missions ... sort of like helicopters with their movable battery trays...
 
Just so everyone is clear: The PC-925 fits in Van's tray when mounted on its side. Odyssey says that this is okay. There is a small gap fore-aft which is easily filled with a piece of aluminum angle. You can make a very small cg adjustment with your choice of having the battery far forward, or far aft, in the tray.
In this placement the terminals are on the side of the battery, not on the top like with a Concord battery.
The PC-925L reverses the terminals from Odyssey's standard. This will put the positive terminal aft, negative forward, when the battery is placed on its side in an orientation with the terminals high on the left side of the aircraft.
If you have a PC-925A (non-reversed terminals) then you will have to "cross wires" with the standard Van's arrangement of master solenoid placement, if the terminals are on the left side; or rotate the battery 180 degrees and put the terminals on the right side, and run the wires over the top of the battery (which is what I do).
Finally, note that the battery uses metric bolts which are smaller than standard battery terminals. For best fit you want 1/4" diameter lugs on the battery cables. These will not fit over a standard aircraft battery post, so you may have a problem if you need to buy a standard aircraft battery when away from home.
 
My Rocket has a IO540 with the NL starter, and a PC680 starts it just fine. 2 years and it is still going strong.

If your battery is up front on the rocket then the 680 does fine. When in the back with 20' #2 ga wire like our -10's, there is higher resistance/voltage drop. The NL starter pulls less amps and turns slower, so it seems the 680 in the back does okay with that starter too.
 
I bought my RV-10 and it has an Odyssey 1200 installed, a little overkill but cranks right up, even after leaving the master switch on overnight! The downside is it weighs 38.2 pounds so with 4 people and luggage, I am aft cg limited so have to keep minimum fuel for landing. However, no ballast needed when solo:D

I am probably going to get a PC925 or PC680 to swap in for family trips so I can carry more luggage (with my family, currently limited to 65 pounds in baggage compartment with 14 gallons min fuel). Easy way to adjust CG for different missions ... sort of like helicopters with their movable battery trays...

I have about 42 lbs of batteries in back and also limited to about 220 lbs in the rear seats with 100 lbs baggage or 320 and no baggage with my wife and I up front. Not really cg limited as much as gross weight(2700 lbs) limited. I have cloth seats and painted interior and built as light as possible. Fuel amount affects cg very little. I bet I will hate not having a/c this summer, but I am so glad I have the spare starting battery.
 
No Ebus, just the standard bus per Vans plan and basic circuitry AFS EFIS, trutrak, garmin, xponder, lights, starter etc.
One alternator to charge both batteries and I can see Ill need another relay switch.
I looked at Z14 and I think that will work for me, but Im still not sure of the circuits for #2 to starter and alternator and how to switch #2 into the panel circuit if needed. Im using an idiot light to signal alternator failure, and battery status volts from the EFIS. I want #2 to service the panel only if needed.
Im trying to keep it simple enough for me to understand, :p and not add on a bunch of boxes. Stokes

The reasons I went with two separate batteries and main/ebus:

Avionics powered up first allows ahrs alignment, get wx, set freq, talk to clearance or ground.
Expensive avionics separated while starting engine.
Spare starting battery and contactor.
No external power plug necessary.
Additional capacity to get me home when alternator fails.

I used a 25 amp diode/heat sink assembly from B&C. Study Bob N., do your research and ask if you have any questions.


I kept the build simple too like you desire. It was affordable, quicker to build and will be easier to troubleshoot/cheaper to maintain years down the road.
 
questions

I have a split buss with avionics seperated from starting except EFIS comes on line with start up so I can have the EMS. I have only one alternator.

My questions is regards to elec bobs Z14 with 2 batteries rear mounted.
Can I wire my aux battery as shown except at the Xfeed contactor bring my single alternator into the aux battery, instead of the aux alternator?
Will this allow the single alternator to charge both batteries?
Will this allow me to feed the buss with both batteries on demand?
Can I use #4awg from the aux battery forward using both batteries on starting (I now have the #2awg on the main battery)? or should I run another #2awg for the aux?

My thougrts are I dont want to re-wire my buss. I want the aux battery to charge from the single alternator. I want to have both batteries on line for starting and service as needed but charging all the time from my single alternator. whheeewww.. makes my head spin. :eek:

How I see it is I will need to add the aux battery and contactor, the xfeed contactor, and diodes on both contactors . Breaker on aux battery. What am I missing?
Many thanks, Stokes
 
Claude,

The only way a single alt will charge two batteries is if they are cross tied together. Well, not entirely true. If you use a diode, you can charge the secoNd battery when the cross tie is open. This is documented in all of the vertical power manuals.

If all you are using this is to have you ems online during start, you may want to look at tcw's ibbs battery.. Bob has a nice product.

Depending what is connected to the other battery, a #4 may be overkill.

I think you need to document all your requirements. You almost have an ebus, similar to what most are using for aircraft that are going to fly ifr. With a little more thought and perhaps another item or two you can have a rather elaborate and rundunant electrical system.

If all you want is your ems online and fly vfr, I would just get a small battery to run your ems and/one edits while starting. To assist with cranking a larger battery may be a better solution.
 
lectric bob

Bob, here is what lectric bob says and this is what I want to do. I just dont know yet how to wire the parallels.

How about a single alternator airplane with electrically
dependent engine and flight instruments? If the alternator
quits, one might wish to assign batteries to Task 1
(engine) and Task 2 (instruments/communication). In this
case, the two suites of hardware are powered from their
own battery busses. Contactors that parallel the batteries
to the main bus are simply opened. The main bus goes
dark and system components that depend on battery
power enjoy separate, isolated sources.
 
thanks

Thanks to everyone who chimmed in for me. I have found what I needed to do. Ill mount my Aux battery in the baggage area just forward of the door behind the rear seat. All I need do is make a ground to the floor and route my power feed to the main battery relay and hook it up in parallel. I dont really need an Ebus all I have to feed is AFS EFIS, garmin 430, pictoral turn and bank and a transponder. My LED lights draw less than one amp and I can turn off the autopilot if need be. My normal draw is less than 10 amps. 2 odyssey batteries gives me 31 amps. thanks..
 
You're right! SEP's web site now shows a higher price. I placed my order with SEP on 30 April, and while I have not yet received the battery I do have an email copy of the invoice saying it shipped, and for $155.

They must have realized they were under-priced but for me at least they honored the advertised price!
 
Crossfeed contactor location on 10? - dual rear battery setup

Planning the wiring for my -10 build currently. Will have dual batteries on a modified tray in the back.

Would anyone care to share pics of their crossfeed contactor install and/schematics?

I'm using the Bob K Z-14 dual batt - dual alternator - dual buss scheme as the foundation.

thank you.
 
Planning the wiring for my -10 build currently. Will have dual batteries on a modified tray in the back.

Would anyone care to share pics of their crossfeed contactor install and/schematics?

I'm using the Bob K Z-14 dual batt - dual alternator - dual buss scheme as the foundation.

thank you.

There should be some photos on my build site. I have dual PC680s, two busses, but I have a VPX instead of a Knuckoll's design.
 
There should be some photos on my build site. I have dual PC680s, two busses, but I have a VPX instead of a Knuckoll's design.
Bob,

I can see that you have the crossfeed contactor on the right side of your batt tray and the dual batt relays on the left. Do you have the crossfeed contactor on its own switch to select for starting or in the event of primary alt failure? Also, are you running dual 2agw wires up the left side of the fuse to the starter contactor?

Thank you.
 
Bob,

I can see that you have the crossfeed contactor on the right side of your batt tray and the dual batt relays on the left. Do you have the crossfeed contactor on its own switch to select for starting or in the event of primary alt failure? Also, are you running dual 2agw wires up the left side of the fuse to the starter contactor?

Thank you.

Actually, the crossfeed contractor isn't being used. I probably should take it out. I have a switch for each of the battery contactors. I can turn both batteries on in parallel, or turn on either one by themselves.

Yes, I used 2 gauge welding wire. It's a little lighter and much more flexible.
 
Planning the wiring for my -10 build currently. Will have dual batteries on a modified tray in the back.

Would anyone care to share pics of their crossfeed contactor install and/schematics?

I'm using the Bob K Z-14 dual batt - dual alternator - dual buss scheme as the foundation.

thank you.
Z-14 Battery Pics

This might help. I did the same as Leffler but without the VPS.
 
Trying something other than Odyssey

In late 2015 I put in a Odyssey 925L to replace a 1200 that was 8 years old. The 925L now needs replacing at just over 4 years. The prices have gone up to $189 so I decided to try the Big Crank ETX-30L for $119.95, no tax and no shipping. Seemed to have good reviews and at nearly 1/2 price at my door I thought I?d try it. Will report back on how it holds up.

TJ
 
Wheelchair battery

Been using the UB12350 battery- weighs about 24Lbs, about 315CCA. I have a full electrical panel and have most everything off for startup except the PFD, thats driven by a backup battery. Never had any issues and at $70 Im fine replacing every 4 years. YTX30L-BS is next on my trying list at 380CCA.

TJ- for sure let us know how Big Crank works out for you.
 
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Big Crank

I've held off on Big Crank only because I heard many say it just flat out stops working after 18 months. But most dont and are really happy with the battery.
Thanks for the future updates!
 
Many of the aerobatic planes use to start their high compression -580's. I think they are being swapped for lithium for weight today.
I had two -680's for 10 years and they did great. I would swap one out every year and then put it in my BMW GS and my family's GS's when they had them. Worked great and I never had a battery older than 2 years old.
I have switched to the EarthX batteries in the back and saved a ton of weight. I am almost always loaded and it really helped the CG when fuel is burned.

There is a noticiable difference between starting power between the Ody and EarthX. I plan on swapping them around 5-6 years.
 
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