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Richard Barnes
05-19-2009, 07:24 PM
Anyone have pictures of house batteries for a 98 Liberty?

Jon Wehrenberg
05-20-2009, 07:03 AM
Do you have a Classic or Elegant Lady? Are they behind the small rear door on the passenger side or are they in the center behind the entertainment center?

Richard Barnes
05-26-2009, 06:41 PM
Do you have a Classic or Elegant Lady? Are they behind the small rear door on the passenger side or are they in the center behind the entertainment center?

Center behind the entertainment center.
Thanks, RB

truk4u
05-26-2009, 08:18 PM
Richard,

Here ya go, current work in progress... Jump in the car, come to Waleska and you can see them in person.;) Do yourself a favor and buy Lifelines with the POG discount. These junk Deka's only went 3 1/2 years.


4861

4862

4863

jack14r
05-26-2009, 08:54 PM
Truk,I think that I might have an answer for why batteries may not last in our Liberty's.If your watchdog is like mine it will not auto start until the voltage is below 22 volts,this is well below 50% discharge.I have asked Liberty what can be done to bring the auto start up to 24 volts,I should have an answer soon.I understand that Liberty does not want its customers to be awakened by the gen starting or stopping during the night,the watchdog is programmed to run for 6 hours after a low voltage auto start,it doesn't matter if the batteries are charged in 3 hours the gen still runs for 6 hours.What I really don't understand is the newer coaches have outback inverters (which are user friendly)which will perform all of the auto start functions and interface with the Crestron system,but Liberty still uses the Watchdog to preform the auto start.If Lifelines are drawn down to 22 volts I doubt they will last any longer than the Gells.

rodburtonmusic
05-26-2009, 09:49 PM
Ok...so needing to replace my house batteries as well. I have 4 of them on my Executive...and I don't have any sort of auto start. Is that a difficult retro fit? What's the best way to go on the house batteries? These pictured look just like mine...

lewpopp
05-26-2009, 09:51 PM
Truk,

Did you have them shipped in from up around Charlotte? I'd do that but to get them off of the truk when it arrives.

Joe Cannarozzi
05-27-2009, 12:04 AM
Jack if you run your gen for 3 hrs right before you go to bed what will the voltages be in the morn? (excluding a/c or heat)

truk4u
05-27-2009, 09:10 AM
Jack,

I don't use the autostart for that very reason and sure wish is was adjustable. The Deka's are AGM, Marine. Mine kicks on at 11.5, but will not turn back off because it's looking for a voltage thats higher than my 13.1 float. Not sure if Brian used it much, but I doubt it. I use 12.2 as the manual starting point. The batteries were so bad while at the Charlotte race, we just came back home and postponed the remainder of our trip up north. The equalizing I did a few weeks ago only helped for a few days and then they were back to 12.4/12.5 as soon as I took off shore power or the gen. I knew this day was coming, but I just put it off hoping to get one more trip in, but I have too much dry camping ahead of me for weak batteries.

My experience with Lifelines have been very good and 5 years is a good benchmark. I completely agree with you that the autostarts low voltage start point will shorten battery life. It's hard to figure out, lower voltage starting over the life of the battery would result in fewer cycles than starting at 12.2. It's all about cycles, so is more better?:confused:

Lew - Yep, shipped from Charlotte to my warehouse...

BrianE
05-27-2009, 11:01 AM
Tom, To answer your question: I never used auto-start. As you said, 11.5v isn't a place you want to be for starting to charge low batteries. I disagree on your opinion of the Dekas however. The battery installation in the 40' Liberty was woefully inadequate in my opinion. Additionally, Liberty's support and assistance of the Watchdog system was very poor. The combination didn't give those batteries a chance to reach their expected longevity. Would suggest now is the time to add a fourth battery (as we've discussed) and contact Magnum and Powertech tech support for assistance in removing the Watchdog and using Magnum's user programmable built in auto-start feature.

As you know, I truly enjoyed the experience of owning the Liberty. The overall design, quality, and livability of that coach is superb in my opinion. It's incomprehensible to me how such an otherwise fine coach was equipped with such a poor dry camp capability. Thanks for giving me an opening to vent my spleen on this sore subject.

Joe Cannarozzi
05-27-2009, 11:17 AM
I have the Magnum auto-start and the start voltage is adjustable but only up to 12.0 or 24.0 depending on witch voltage your running.

I know 12.2 is the magic # but that is a resting voltage and so if you drag them down to 12.0 under load that is IMO just right. Depending on size of the load 11.9 could be O/K and better if it is large load like a residential fridge.

When it goes on the run time is 3 hr, preset nonadjustable. It has a quiet time override and can be programed to cycle the gen on a timed sequence instead of a low voltage start. Finally you can wire the thermostat from one of the house a/c units to it and it will auto-start when that a/c calls for cool and again, run for 3 hrs.

I got it for 159 bucks from the cruise-air guys, they have them. I later found out they undercharged me by a couple hundred dollars, I believe they are around 350. Comes with a remote.

The Liberty autostart has the ability to autostart when low shore or gen voltages become evident, this unit will not do that.

GDeen
05-27-2009, 12:40 PM
Hopefully this is close to on topic....

With a good set of house batteries, how long can one expect to run a couple of A/C's for instance?

Maybe more appropriate, what can be expected in terms of background use for over night from a good set of batteries? One A/C and some lighting? No A/C's?

Joe Cannarozzi
05-27-2009, 12:52 PM
Although it is possible to run a/c off of inverters it is almost impossible to do it without the bus running or shore or gen power available and I do not believe it was the intent of designers to do so.

I would be surprised if you could get more than a couple of hours trying to power a/c off inverters w/o input power, along with all the other the essentials like the fridge and such.

Excluding a/c, even a weak set of batteries should be enough to get you 8 hrs overnight.

GDeen
05-27-2009, 01:18 PM
Although it is possible to run a/c off of inverters it is almost impossible to do it without the bus running or shore or gen power available and I do not believe it was the intent of designers to do so.

I would be surprised if you could get more than a couple of hours trying to power a/c off inverters w/o input power, along with all the other the essentials like the fridge and such.

Excluding a/c, even a weak set of batteries should be enough to get you 8 hrs overnight.

Thanks Joe - that makes sense certainly, but I was curious after reading different threads on inverter use during quiet times, etc.

phorner
05-27-2009, 01:19 PM
A couple of comments....

On our previous coach, I could program the auto start through the inverter control to start at almost any set point that I wanted such as specific voltage or percentage of state of charge, and the options for the generator to shut down included manual, float charge, or a specific voltage. Very easy and user-friendly. I sure wish I had that same control in my Liberty.

Regarding the dry camping issue, we have never had a problem with the batteries lasting through the night, say 8 to 9 hours.

Actually, we've had them last through much of the day if we're away from the bus. Of course, with minimal loads. Usually, I would run the generator from about 3 or 4 in the afternoon until 9 or 10 at night. That seemed to be plenty to provide AC for cooking/cooling/etc. during the "busiest" part of the day and keep the batteries up the rest of the time.

If we stayed up later and watched TV for a while after the generator was shut down for the night, sometimes I will run the generator for a couple of hours first thing in the morning before leaving the bus.

I think that you should expect the batteries to easily make it through the night with light loads.

Unfortunately, I have no experience trying to run AC loads on battery power.

truk4u
05-27-2009, 04:53 PM
Gordon - Most of the Marathons will run 1 A/C for 4 to 5 hours or 2 A/C's for about 2 hours on the inverters. I had a 97 that I put in all new house batteries and I could easily get that usage. Keep in mind, those were 2 4,000 watt trace inverters and 6 4D AGM Lifelines. If you have a good set of batteries, like Paul said, overnight is no problem with conservative use of the power. Like the others, I run the gen for about 3 hours before bed and your good to go.

Brian - If money was no object like Jdub & Mango, I would for sure convert this Watchdog nightmare over to the Magnum's auto-start capabilities.

Joe - I don't know how you could call the 12.2 a resting voltage when dry camping. There is no battery resting in my dry camping, something is always calling for power. I do agree that 12.0 is probably an OK number and once again, it's all about cycles.:)

Richard Barnes
05-27-2009, 05:00 PM
Richard,

Here ya go, current work in progress... Jump in the car, come to Waleska and you can see them in person.;) Do yourself a favor and buy Lifelines with the POG discount. These junk Deka's only went 3 1/2 years.


4861

4862

4863

How do you go about getting the POG discount and do you know of dealers in the Southern California (Long Beach) area?

RB

Jerry Winchester
05-27-2009, 05:07 PM
Gordon,

We run one or two AC's all the time on the batteries and the time really depends on the temperature. I have had them run 2 or 3 hours before the generator started and I have had them run 8 hours. The big amp draw is the compressor is running, so if it only cycles on intermittently, then you get longer run times.

truk4u
05-27-2009, 09:47 PM
Richard,

If your doing the work yourself, just call Lifeline, tell them your a POG member and they will ship them to you. If you have the work done by some shop or dealer who also sells you the batteries, you will obviously pay more.
I thought you were near Atlanta according to your screen address, so I know you won't be visiting.:p

GDeen
05-27-2009, 09:53 PM
Thanks fellas - sounds like with good batteries you have some options for invertor only use overnight if conditions aren't too demanding.

garyde
05-27-2009, 11:42 PM
I came home this afternoon and smelled the depressing scent of batteries gassing off. My Batteries are new lifelines. So, after checking everything on the inverter/chargers, I decided to turn the system off for the night.
Lifeline manual says a small amount of gassing is not unusual but I have never smelled anything before today with these new batteries.
I lost power to the Coach about a week ago and everything was drawn down but I have not had any other problems.
If anyone has additional information, I would appreciate some input or I'm faced with getting in there and testing each individual battery.

jack14r
05-28-2009, 08:25 AM
Joe,I was out of town yesterday and could not answer,You asked what would be my voltage without AC or heat in the AM,I really don't know,but if it is cool enough on any of my next trips I will find out.Liberty has said that they will help with the watchdog to get it set up to auto start at 24 volts and I will also try to get it to turn off after 3-4 hours of run time.I will determine that after a few more trips.

TG Transport
05-28-2009, 01:23 PM
I can concur with the same experience that both the Liberty and Marathon owners have had. The Watchdog on our Liberty was a source of periodic frustration which we had fixed on several occasions. I ended up writing some of its performance off on the age of the 1994 coach technology. Bottom line on that bus was that Autostart did work if you left the coach unattended for a significant period of time. Yet while we were in the coach I tended to run the genset to coordinate with our power usage and sleep schedule. AC would not run unless on shore or generator power anyway so battery life was as much as 12 or more hours merely running refrigerator and a few lights.

Currently I let the Marathon kind of do its own thing unless we are camping where there are specified hours for generator use. Batteries will run AC up to 2 AC units somewhere from 2 to 8 hours much like Jerry stated. My batteries are 2 years old and I am starting to see a very slight decrease in stored capacity. This thread has got me thinking about set points but in my past discussions with Marathon they have been pretty confident with their stock settings. I am open to any comments which would increase their lifespan....

Richard Barnes
05-28-2009, 06:41 PM
Richard,

If your doing the work yourself, just call Lifeline, tell them your a POG member and they will ship them to you. If you have the work done by some shop or dealer who also sells you the batteries, you will obviously pay more.
I thought you were near Atlanta according to your screen address, so I know you won't be visiting.:p

I'm in Southern California now but will return to Atlanta late June. I'll do the work then. Thanks for the info.
RB

Ray Davis
05-28-2009, 06:43 PM
Richard,

Where are you in SoCal? I'm sure many of the local guys would love to get together and meet up with you.

Ray

Joe Cannarozzi
05-28-2009, 10:59 PM
Towson where does your Marathon auto-start, lower than you are comfortable with?

That mark is a moving target. If the draw is great you can go deeper between charges than if the draw is minimal.

If you are just running 1 light for security during outdoor storage you would want it kicking in right at 12.2 but if you are regularly running a couple of a/c's on them they can get down into the 11's safely.

That point should be able to be conveniently adjustable to some degree.

0533
05-29-2009, 09:00 AM
Richard here is the contact and pricing for Lifeline:

Yes we do offer special pricing to POG members.

Normal retail cost for the GPL-4DL is $466.59 + shipping

POG Member price is $380.45 (freight included)

Let me know if you need any more assistance.

Thank you for contacting us.

Best Regards,

Justin Godber
Lifeline Batteries
955 N. Todd Avenue
Azusa, Ca 91702
Tel - 626-969-6886 x 221
Fax -626-969-8566
Email - justin@lifelinebatteries.com
Web - www.lifelinebatteries.com

Jon Wehrenberg
05-29-2009, 09:16 AM
Truk,I think that I might have an answer for why batteries may not last in our Liberty's.If your watchdog is like mine it will not auto start until the voltage is below 22 volts,this is well below 50% discharge.I have asked Liberty what can be done to bring the auto start up to 24 volts,I should have an answer soon.I understand that Liberty does not want its customers to be awakened by the gen starting or stopping during the night,the watchdog is programmed to run for 6 hours after a low voltage auto start,it doesn't matter if the batteries are charged in 3 hours the gen still runs for 6 hours.What I really don't understand is the newer coaches have outback inverters (which are user friendly)which will perform all of the auto start functions and interface with the Crestron system,but Liberty still uses the Watchdog to preform the auto start.If Lifelines are drawn down to 22 volts I doubt they will last any longer than the Gells.

Take this with a grain of salt because it may not apply to all Libertys.

My Watchdog has a voltage sense wire that runs through a 1 amp fuse. It is located on a multi fuse block on the LH electric compartment side panel. Assuming from Jack's post the generator run is a timed event rather than one controlled by a battery voltage such as 27 (or 13.5) volts then the Watchdog start voltage can be adjusted by an addition of a resistor that will convert and actual voltage of XX to the lower value that starts the Watchdog. Someone with electrical skills beyond mine can figure the resistance value required, but it should be an easy thing to do.

Richard Barnes
05-29-2009, 11:43 AM
Richard,

Where are you in SoCal? I'm sure many of the local guys would love to get together and meet up with you.

Ray

Ray, I'm in Long Beach and I work here M-F and then fly home to Atlanta on the weekends (when I can). I'd love to meet up with folks here as would the lovely Mrs. Barnes when she comes out. I keep the coach in Long Beach except for work related travel or weekend get aways. We just returned from a weekend in Yosemite.

RB

Richard Barnes
05-29-2009, 11:47 AM
Richard here is the contact and pricing for Lifeline:

Yes we do offer special pricing to POG members.

Normal retail cost for the GPL-4DL is $466.59 + shipping

POG Member price is $380.45 (freight included)

Let me know if you need any more assistance.

Thank you for contacting us.

Best Regards,

Justin Godber
Lifeline Batteries
955 N. Todd Avenue
Azusa, Ca 91702
Tel - 626-969-6886 x 221
Fax -626-969-8566
Email - justin@lifelinebatteries.com
Web - www.lifelinebatteries.com

Thanks for the info. I'll be in touch with them. I really appreciate it.

Ray Davis
05-29-2009, 01:17 PM
Richard,

Many of us are in Southern CA, maybe 30 minutes away. Would love to connect some evening and get together for dinner. Maybe we could get a group to meet half-way?

Ray

TG Transport
05-29-2009, 05:36 PM
Joe, I will look this weekend but memory says that it kicks on at 11.8 - at least thats when the Techlink system says the batteries are depleted.

truk4u
05-29-2009, 08:19 PM
Jon,

Good idea, where are we going to find the electrical wizard to help with this problem?

I was incorrect when I stated my auto-start activated at 11.5, it's actually 11.15 according to the Liberty Manual, that's even worse. It also states that the gen will run until 13.6 volts are achieved.:eek: My bulk and absorbtion charge is 14.2 and float is 13.1. So in theory, the gen would shut off during the bulk/absorbtion cycle. My float will never get it to 13.6, so what were they thinking!:confused: I do know that it will not shut off and continues to run indefinitely.

This Watch Dog thing must be some dark, secret, hidden for Liberty Eyes only since there is no way to make any adjustments.

Jon Wehrenberg
05-30-2009, 01:31 PM
Truk,

I based my idea on Jack's 6 hour generator run time.

If the generator run time is not based on hours in the Watchdog, but on house battery voltage then the idea of using a resistor in the sense line is invalid. A resistor will make it start sooner, but since the voltage will read lower than actual it will never be seen by the Watchdog as being at a high enough value. To address that would require the addition of a relay and some additional wiring.

The Watchdog is a deep dark secret and if there were any single lousy feature on a Liberty this feature has to be near the top of the list, if not at the top of the list. If I were not content to manually start my generator and to monitor my voltages that alone would put me in another coach.

Even if the Watchdog is solely dependent upon battery voltage for starting and stopping I think a modification to the sense wire circuit could be implemented. The first step would be to install a resistor in the sense wire circuit so the generator would start at some new higher value such as 12.25 volts. As soon as the generator started, use a relay with a 120 volt coil that is closed upon generator start to bypass the resistor and allow the Watchdog to "read" actual voltage in the sense wire while the generator was running.

I could easily create the circuit, all I would need would be someone to get me the correct resistor value to change 12.25 actual volts into 11.15 volts to fool the Watchdog into starting prematurely.

jack14r
05-30-2009, 02:39 PM
Jon,I don't think that the watchdog shuts the generator off based on voltage but shuts down only on time.I think your resistor method would work fine except I would like to reduce the run time to possibly 3-4 hours which should fully charge the batteries.I will be dry camping in 2 weeks and I will verify how long it takes to fully charge the gels from 12 volts to 14.1 volts.When the batteries reach 14.1 volts should I maintain the bulk charge for some period of time to fully charge the batteries?

Joe Cannarozzi
05-30-2009, 09:09 PM
My Magnum is like Jack's it goes on with voltage but then I can adjust that easily but once it starts it will run for a 3 hr period and that is not adjustable. That is just about perfect timing to get us from 12.2 to 13.1. They get there around 2&1/2 hr+.

I have found I do not need it. I will run the gen when I get up 3hr and before bed 3 hr unless it is warm the gen runs as long as it needs to to keep comfortable.

I do not like to let the gen run when I am not there even though it could, why invite potential problems.

Right now 8 hrs of gen time is 20 bucks, a small price to pay for comfort and convenience where there would be none.

Jon when the charge starts and the charger is giving them 30amp they are at 14.1 almost immediately and as the charge rate goes down so does the battery voltages till the charger drops off to 10 amp then float and the batteries follow at 13+ to 13 even or so.

That would mean you would be trying to sense getting back to 13.1 to get it to shut down at the right time?

I think 3 hrs is a pretty close universal time frame to get from 12.2 to 13.1 on most coaches who else can add data here?

truk4u
05-30-2009, 09:29 PM
Jack,

I don't think you get the batteries 100% charged until float is achieved. Also, on mine, bulk and absorbtion are the same charging voltage 14.2.

JIM CHALOUPKA
05-30-2009, 09:51 PM
Just call Nick Hessler and see if he has any ideas on the subject.
I think he would like to have a product of his own for the RV market.
He sure is knowledgeable enough. If he wanted to do it I think he could!
His old cell number is 541.321.2545.
If that's not current I think Ray has his number.
He could probably make a kit to add or a whole new watchdog type gizmo from scratch to do what is necessary!

JIM

Jon Wehrenberg
05-31-2009, 05:48 PM
The charge rate of the batteries is dependent upon how the inverters are set up.

I have my inverters set up for the lowest charge rate because we rarely dry camp. You will go into float a whole lot faster if you set the inverters up for maximum charge rate. Then when you are on shore power trying to manage loads you have to remember how you have the inverters set up so you do not trip the power outlet relay.

For example, on a hot night with a heavy load on the 50 amp power outlet turning on a lot of coach lighting such as the Tivolis the inverters will ramp up the power to keep the batteries charged possibly tripping the power outlet breaker.

If you find out exactly how the logic is on the Watchdog (time or voltage?) pass it on and I will try to experiment on my caoch to develop a way to start with a higher voltage so the batteries have a longer life.

One thing everyone needs to consider. I don't know the answer, but it is one that can probably be plotted.

A 50% maximum discharge may give the batteries a life of 5000 charge / discharge cycles. A discharge down to 10% remaining life may cut the number of cycles to 1000. The question I have is how many hours of use before the batteries reach 50% versus 10%, and does the number of life cycles match the number of times the generator will start regardless of which rate of discharge is selected? Obviously starting the generator at 50% means it is going to start more often than if the batteries are allowed to go down to 11.15 volts before recharging.

jack14r
05-31-2009, 06:47 PM
Jon,You are right about the AC current draw and tripping the breaker,I can adjust the outback inverter/charger down to 5 AC amps.Liberty wants them set up on 50 amp service at 18 and 10 amps,and this will almost always cause a problem with current draw.The other thing that I don't like is the chargers are set up for 4 hours of bulk charge and 2 hours of float charging,this is a problem because whenever a current source is changed it goes into bulk charge for 4 hours.I adjust mine based on the needs of the batteries.If I plug in after driving it will go to bulk charge even though the batteries are fully charged.My Marathon with the trace inverters would do the same thing.This can not be good for any type of batteries,and I think that this would help sell more batteries.The systems that we have for charging are not smart therefore we must adjust and monitor the chargers to deliver the correct voltage and current based on the condition of the batteries.

truk4u
05-31-2009, 09:34 PM
I agree, there is no doubt each inverter manufacturer handles the job a little different.

With the Magnum's, after driving, the batteries are well charged and mine immediately goes to bulk, then absorbtion and float rather quickly. The entire process takes less than 1 hour, but I haven't kept exact time. Before I hook to shore after driving, I turn off the chargers and turn them back on later after all the power needs sort of get worked out. There's no hurry for the chargers, so I wait.

Cycles are the big question in battery life. How you use your bus determines the cycles based on your particular charge parameters. Here's a few numbers to think about using Lifeline's AGM data:

Expected Life Cycle - 5000

Discharge - Voltage - Life Cycle
50% - 12.20 - 1000
75% - 11.75 - 600
100% - 10.50 - 375

So in theory, if I am diligent about my new batteries discharge rate not exceeding 50% (12.2 volts), I can expect about 1000 cycles. I will use more cycles than the guy who uses 75% (11.75 volts) and gets 600 cycles, but will I reach the end of my battery life before he does?:confused: I will also use the generator more often and use more fuel, but using the gen more in my opinion is a good thing.

Now I throw my auto-start into the picture and with the Liberty Watch Dog default start voltage of 11.15, approximately 90% discharge, I now only have about 440 life cycles. Batteries are very expensive!:(

I'm sticking with 12.2 per Lifelines recommendation, manually controlled of course:mad:and hope it all works out.;)

Joe Cannarozzi
05-31-2009, 11:16 PM
Jack the way your bus forces a charge on full batteries after a long drive, that's not right. What is Liberty's explanation for that?

Ours functions just like Toms.

I do not turn off the inverter when first hooking into shore/gen like Tom but with the batts charged up the inverter will really quickly go thru its cycle and into float. When we leave town I do not turn the inverter off till we get home.

Jon we are not able to adjust our charge rate on our older Heart in the back of the remote but have to do it directly on the front of the inverter itself and it is downstairs behind a wall, behind the freezer. Again because of the fully charged condition of the batts any time we end a day I have never adjusted ours down, it has been a non-issue.

Winter forces me to manage power more than summer.

The only time I can get the inverter to ramp up to 30 amp rate is if we are dry camping we have been running off of it for 8 hr or so and when I start the gen I want to see 30 amp anyway, not 5.

It's great to have all these choices. If we had the convienience to adjust our charge rates like you we probably would but even so it does a pretty good job all on its own. Jon could you adjust your 87 at the remote too?

I think these 15 and 20 K power plants and large corrisponding inverters/dc capacity are one of those things that set us apart.

phorner
06-01-2009, 08:43 AM
It sounds like the inverter manufacturers that provide control panels that can control generator auto start do a very good job and allow for the precise setting of start/stop parameters.

Maybe it would be beneficial to explore the possibility of replacing the converter's auto-start system with the one offered by the inverter manufacturer?

My old system would allow me to set the auto start at 90% capacity and stop at float charge. The display would also tell me how many hours to go based on the existing current draw. It worked flawlessly.

It might be simpler to research this retrofit rather than re-engineer the converter's system.

Any thoughts?

ajducote
06-01-2009, 09:12 AM
On my 99 Royale, I wired one of the inverters to control the generator auto start. You can set times and voltage points for bulk, absorption and float.
It was a job to get the wiring figured out. I will try and find the wiring diagram I created and post it.
Works much better then the auto start that was installed by the converter.

BrianE
06-01-2009, 11:33 AM
Andre,

It was news to me that the autostart system in our Royale #265 is not controlled by the Trace panel. The differences in systems between the Royale and our old Liberty have kept me busy enough without worrying about the autostart system which I have never used in either coach. The current thread has however kept my attention about battery charging and your comments definitely woke me up.

I just spoke with Glen Burden at Royale Phoenix and asked him to review the autostart system for me. He confirmed your info and told me the autostart low battery cut in is preset and not controllable at 11.4 volts. He also told me he has a diagram for accomplishing what you did in allowing the Trace inverter to control the autostart and charge parameters. He recalled a relay and 110v line was needed in the circuit to make it work and that he would dig the diagram up and send it to me. It will be interesting if it is similar to your setup.

Many thanks for the heads up. As always POG is a great tech resource as well as a place to meet good friends, sheep-lovers, annal mechanics, and taco freaks.

lonesome george
06-01-2009, 12:45 PM
Our coach uses a Sun Selector to auto start/stop the generator, the thing works OK and the start and stop voltages can be adjusted by .1 of a volt which is good. The current setting are start at 12.0 and stop at 14.1 from this thread it looks like the 12.0 should be changed to 12.2.
My question is if the inverters can be wired to start and stop the generator why is the Sun Selector, Watch Dog or some other device there in the first place? Is it the covenience of a rocker switch on the Instrument Panel?
For reference our rig has two 4000w Trace inverters, six 8D AGM's and a 20 kw generator.

BrianE
06-01-2009, 02:02 PM
George, The advent of the inverter controlled genstart system is relatively new. Why the converters didn't take advantage of the feature when it became available in the mid-90's is anyone's guess. Also the 11. something value the older systems use to trigger autostart works okay with lead acid batteries but obviously isn't okay with AGM's. The 12.0 that your system is set up for is presumed to be just fine according to the Battery thread that just preceded this one.

Jon Wehrenberg
06-02-2009, 08:35 AM
In problem solving it is best to eliminate variables or unknowns and in this discussion we are all considering a global problem relating to autostart and battery charging. Apples and oranges.

I see two distinct issues that need to be separated. The first is recognizing the autostart parameters for our repsective coaches. What may be the Liberty Watchdog start/stop parameters may not be the same for any other conversion, or even a Liberty that has been modified.

I think if Jack can discern the start/stop parameters for example we can likely resolve how to modify those while leaving the Watchdog system unaltered. I cannot say that about other autostart features because my understanding of those is worse than what I know about the Watchdog (which is minimal).

The charging cycle for our inverters is another whole issue. Some can be easily changed to reflect our individual needs. Setting inverters up for high power charging is as easy as following the inverter manufacturer's instructions, but in some cases it may require access to the rear of the remote panel. In other cases it might just involve some button pushing from the front, or as Joe points out, gaining access to the inverter itself. There are times when the charging parameters need to be reset, such as when we have power management issues with a 50 amp service and we need to have 3 AC's running along with everything else we need operating. Other times we need a high charge rate on our batteries because we may be pulling a lot of power from the batteries and we need that high charge rate to avoid discharging the batteries.

Some inverters are designed to go to bulk on every inititation of the charge cycle (a warning to owners of gel cell batteries....that's not good) and others may just need to go quickly through the various charge phases only to measure voltages. But part of the charging system also involves the bus driven alternators which are charging to a single specific voltage and DO NOT go into float. As if that is not enough to worry about, recognize that the bus driven alternator can be supplying charging voltage, and if you are running the generator (such as to use AC) the inverters are also charging the batteries. Their voltage output may exceed the bus regulator set point so the resultant voltage may be a bulk rate voltage from the inverters. Confused? Don't be. Just be aware of these things and make absolutely certain the various chargers are set up for your type of batteries (a gel cell battery is as good as dead if you charge it using a lead acid or AGM protocol) and that you clearly understand how your system works.

Joe Cannarozzi
06-02-2009, 11:01 AM
D/C Power 101

I am confident I understand float but I would like to know more about the difference between bulk charge and absorption charge?

Jon Wehrenberg
06-02-2009, 12:52 PM
Joe,

It's voltage. By the time you read this site you will be volunteering to put on the DC Power 101 seminar.

http://www.windsun.com/Batteries/Battery_FAQ.htm#Using%20a%20deep%20cycle%20battery %20as%20a%20starting%20battery

Every single RV owner should read and understand this information. It will pay dividends many times over.

But here is another that has substantial value and information.

http://www.lifelinebatteries.com/rvbatteries.php

If you really want to go further, here is another site that will add to your depth of knowledge.

http://www.wholesalesolar.com/information.html

As an alternative, do what I do. I make stuff up.

This whole topic of batteries, charging, inverters, etc. is central to enjoying an RV. If you are constantly having problems with battery life, maintaining a charge, overloading circuits, or just don't know what you should be checking or looking for, the above information is about as good as it gets. There are no free lunches so we are all forced to compromise. We only have a finite amount of battery power available so we all need to understand how to prolong the battery life, how to conserve battery power, how and when to charge the batteries, what type of batteries are best for our needs, and if we need to modify how we use our available battery power. An alternate source of information is the operating manuals and owner's manuals for everything from our inverters to our chargers to our batteries.