6D vs 8D and also how many of either.

[Joe Cannarozzi]

I would like to spur some conversation on hands on experience and performance and preference.

It should all be a matter of necessity based on components but some campers out there are incorrectly outfitted.

So what have you got?

8D and how many or 4D and how many and how many a/c if any are running off of them. Have you been able to compare the set-up with previous buses or performance of others buses?

[dale farley]

We have six 8D's and a place for 2 more if I needed them. Don't run any AC's off the batteries.

[Joe Cannarozzi]

O/K Dale great we know yours are recent. How long can you go till they get half discharged?

[dreamchasers]

I would like to spur some conversation on hands on experience and performance and preference.

It should all be a matter of necessity based on components but some campers out there are incorrectly outfitted.

So what have you got?

8D and how many or 4D and how many and how many a/c if any are running off of them. Have you been able to compare the set-up with previous buses or performance of others buses?

Joe,

I can only comment on what type and how many I have. I have 8 8D batteries and the batteries are wet cell, VLRA type (not AGM or gel, wet cells with recumbent valve tops). My batteries are not in good condition and do need replacement.

I am holding out to do the change out this winter.

With my old batteries my coach will stay above 12 volts for 12 - 14 hours.

I do not have the capability of running ACs from batteries.

An interesting post.

Hector

[Joe Cannarozzi]

Hector that is very good performance from an aging set of batteries.

The compromise is weight and space and replacement costs.

Hector how much space does 8 8-Ds take up a whole bay?

No matter, I am coming to the conclusion overkill in this department is desirable.

Jack mentioned that he knew of a comparison between 8 4d-s and 6-8d,s I think.

he needs to reiterate. The man has successfully altered his Liberty watchdog system to auto start correctly. Great work Jack.

Those buyers concerned with "orphan coaches" As long as there is POG and the camper is on a prevost chassis there are no orphans, I digress.

[jelmore]

We have 3 8D AGM batteries, two years old. When dry camping, we let Liberty's Watchdog start up the generator. I think that set point is 11.2 volts, seems I read that here someplace. Haven't checked that to confirm.

From what I presume is a full charge (no significant charger activity), we get 8 to 12 hours depending on what we're doing. The low end is with the big refrigerator on all the time, computers, hard drives, case fans all on, satellite dish on, basement refrigerator on, make coffee, watch some tv. It's the microwave at the end of the cycle that will usually cause the generator to start. The high end is easily achieved by turning off all the small things and turning off the refrigerator for 3 or 4 hours, a couple of hours at a time.

Liberty doesn't run any air conditioners from the batteries and I don't think there's room for any more.

[Pete]

Joe, I have eight 8D's and two 3,600 watt Vanner inverters. I can run two A/Cs (front and rear) from inverters. The entire coach will run on inverters..microwave ,fridge, 2 tv's and all lighting from inverters (of course can't run the range). I have used inverters to overnight many times, but if I need A/C I use the generator. I honestly cannot tell you how much drain there is on the batteries, but the generator has never started on auto start.
I agree that it is over kill, and frankly, don't think, other than the fridge, tv's and limited lighting are all you need on inverter. RUN THE GENERATOR!
My previous bus, a 1985 American, had a 1500 watt invertor, and four 8D's (lead acid) handled the tv's and some lighting worked just fine. The fridge though was a 12v/110v unit which worked great except for the small size.
I will seriously consider reducing the number of batteries the next time I have to replace them, and use the generator more. The batteries and the inverters take the entire third bay on the curb side.

[Jon Wehrenberg]

I have 4 8D's. I am a generator user. Even if I pull into a rest area for a sandwich I run the generator to be able to run the AC units. Ditto if we overnight in a rest area. The generator goes on immediately. I do shut it off when we go to bed unless we need to run the AC's. When we get up in the AM the voltage is usually around 24.5 to 25.0. But the only loads are usually the refrigerator and the TV plus the usual key off house loads such as alarms, tank level sensors, dash radio memory, clocks, etc.

As soon as we get up the generator goes back on unless I intend to drive immediately.

I have no idea how my autostart works since the first time I saw my voltage on the house batteries sink below 23.8 volts and the generator had not yet started I decided from that point on to always manual start my generator.

[JIM CHALOUPKA]

Jim, how are you able to only have three batteries?
Do you not have 24v?

JIM

[Joe Cannarozzi]

He has a 12 volt house.


Jon went to some length to both inform everyone of the importance of being able to bypass the inverters and then upgraded his system.

Here is some smart design

Here is the inverter and the leads going to and from it both a/c and d/c in and out on our bus.
4978

The connectors he used for the a/c input and output are twist-locked and they are flip floped
4979

I can unplug the inverter and plug the bus leads into each other completing the circuit for the whole inverter sub panel. It is a good simple solution.

4977

I have a 2500w Heart inverter and today I moved the power lead for the front cruseair over to the inverter sub panel. With the bus running on high idle and the alt charging the house it started up the unit and worked fine.

I had 25 house volts and it was pulling 13 amps:) I kicked on our U-Line ice maker that is the only other constant draw (we have propane) and the draw went up to 15 amp voltage holding strong at 25.

So it is no different than any other appliance or accessory on the inverter. I have to manage my draw or I will blow the 20 amp breaker on the inverter.

If I decide I will hook it up permanent I will need to put a switch on the a/c so I can switch it back to the main panel when camping or it would be a PITA power managing.

Kinda cool runnin my front cruise with a bus with only 1 2500w inverter.

When we first bought the OTR did not work and we had experienced the dreaded compressor shut down rolling north on I-65 on a 90s day........Water Misters, that's the ticket. again I digress.

Thumbs up on the inverter instalation Mr. Hickox

[Jon Wehrenberg]

Huge advantage being able to access the inverter area. That is a perfect solution and anyone that wants a simple project can do something like that.

Good pictures Joe.

[rahangman]

Joe, when we get to your place, would like to have that simple solution put to my bus. I find myself running the genset for AC while traveling

[Joe Cannarozzi]

We might be able to get that done.

Jon I pull my freezer and 2 panels and it is in the middle of the second bay in front of the aux fuel tank, gen and its radiator other side.

I was very nervous when we first bought but now I zip through stuff.

4980


If you look on the right wall high there is a louvered vent and the panel I removed is perforated I have passive ventilation. When the freezer is on (always) it is passing its heat too. I think I am going to do that better.
4981

4982

Getting back on thread

Question: is it possible to have a bus with 8 8-D batts AND otr a/c or is design forced by function on this?

If I was setting a bus up it would have all that plus cruise airs and an aqua-hot and long range fuel tanks. Is there enough basement on an XL to set one up like that.

[dale farley]

The last time I checked the drain on my batteries (3 year old batteries), I could run the refrigerator, lights, etc. for about 9 hours before the batteries reached the 50% level.

[phorner]

When checking the battery voltage prior to generator start-up (either auto or manual) what are you using?

I just have the bar graph on the inverter panels, and they only register half-volt intervals, and I'm not confident as to their accuracy.

Is there a better indication that I'm missing? I do also have an analog display on the dash..... more accurate?

[Jon Wehrenberg]

Paul,

On mine they are quite accurate.

I have measured my voltage at the batteries with the meter and that voltage, the voltage at the equalizer, the inverter panel voltage and the dash house voltage gauge were all close enough for government work.

[phorner]

Jon,

Thanks. I like to keep an eye on the dash analog gauge.... just seems to give me a "finer" reading of voltage, but I can't come up with any logic to that.

[Steve Bennett]

Our coach has 6-4D AGM Lifelines, and 2-Heart 2,800 watt inverters. It will stay up for 12+hours above 24 volts with a good charge, running the refrigerator, satellite, TV's, lights, & Webasto for hot water. We need to run the generator for the Cruise-Air A/C's if it is hot.

[jack14r]

I have 6-8D's gels and Liberty wants to keep the gen off as much as possible so the watchdog does not activate the auto start until 21 volts.This low voltage has killed the batteries in 1 year,I am going to get 6 new lifeline 8D's tomorrow.I figured out how to fool the watchdog to auto start at 24 volts and it works perfect.My coach has 2 outback 3500 watt inverters and it will run 2 cruise airs off the batteries,I knew I had a problem a few weeks ago when the batteries would not last 8 hours without any AC on,on Friday I smelled a battery venting and I called Lifeline.I have the panels etc.out and the batteries are ready to come out.I should finish the install by Tuesday.The POG deal on Lifeline 8d is 434.16 and they have a warehouse near me.Thanks POG/Jim Skiff.

[garyde]

In my Trade, Installing UPS equipment and Generators, Panels etc. The design is base upon Generator failure, and the UPS batteries are a backup to the generator. We purchase qty of batteries based upon the amount of minutes or hours the customer wants to keep their Computers, servers etc. up and running. UPS is not designed for a/c or motor load.
In the RV design, it's the other way around, RV folks depend upon their batteries when dry camping and the Generator is the back-up.
The difference is in the purpose of use. Rv folks don't want to run their generators if they don't have a need. That puts all of the load and use on Batteries. Each 8D battery weighs approx. 150lbs. Four batteries is 600lbs. and 8-8d batteries is 1200lbs.
The same issues with both design is the amount of time the batteries will last. On the Building design it is critical because the generator has failed. On the Rv side its less a critical failure and more a convienace matter. You can always shut load off, or start he Generator or Engine for that matter.
I have no idea why Liberty has such low settings for Gen start on low battery but you can extend the minutes on your batteries by reducing loads.

[sawdust_128]

This is a site I use often for info on inverters and batteries. Good, well written materials.


http://http://www.xantrex.com/support/web/type/7/docldoc_type.asp

[jelmore]

A great resource. Thanks. Power sharing and charge current finally explained!!

[truk4u]

Jack,

Anyway to fool my old vintage watchdog as you have done? PM if you want.

[mike kerley]

Joe,

We have 4 8D's AGM's. Two heart 2500 inverters.

No ac on battery/inverter power. All electric coach so lights, TV, refrig etc .

We get about 8-10 hours before batteries are in the low 12's. Auto start does not kick in until about 11.5 which is too low.

[Joe Cannarozzi]

Mike yours looks like a pretty common set-up.

Are those new batts? If so how long did 4 8-D get you with the old previous ones. How they preform when they get old is more important than new.

[jelmore]

This is a site I use often for info on inverters and batteries. Good, well written materials.

http://www.xantrex.com/support/web/type/7/docldoc_type.asp

Of particular note to those with Freedom units, for example 2000 Libertys...

Load sharing, what it is:
http://www.xantrex.com/web/id/255/docserve.aspx

And controlling charging current:
http://www.xantrex.com/web/id/702/docserve.aspx

As far as I know, none of the above is covered in the owner's manuals.

[Joe Cannarozzi]

Jelmore I can feel the joy of your new info all the way over here:)

I think regardless of how you use your coach it should still have enough battery capacity to get you 8+ hrs, staying above 12.0, with no air conditioning loads with a set of batteries at the end of their suggested useful lifespan, 5yr.

Mike how old are your 4 8-D's

[Joe Cannarozzi]

Another question.

Only those of you that are set up to run multiple air conditioning off of inverters.

How many batteries and what size are they.

[mike kerley]

Joe,

These are almost two years old. The ones I removed were 6 years old and they would be at 11.5 in a couple of hours. They are easy to get to on the CC, but considering the weight of each battery, I opted to have them changed and save my back! I'll never put another wet cell back on a house system. They require way to much maintenance...

[jelmore]

Another question.

Only those of you that are set up to run multiple air conditioning off of inverters.

How many batteries and what size are they.

Joe, obviously I don't run air conditioners from the inverters, but looked through some of the documents that sawdust sent links to.

This one discusses running an air conditioner from an inverter:
http://www.xantrex.com/web/id/698/docserve.aspx

And this document covers battery banks and how to connect them to inverters. Also cover current loads and has a worksheet for computing all this.
http://www.xantrex.com/web/id/1526/docserve.aspx

[gmcbuffalo]

Joe
In 2000 the previous owner of my coach converted the inverter battery system over to Three 3000W Combi Freedom inverters on a battery bank of Eight 4D's. One inverter only charges when the generator is on, and the other two work on shore and Generator. I did find out this last month that I can run the Rear and Mid AC off the generator while underway. The Front AC only works off Shore or Generator power. I have never tried running the two AC of the inverters with shore power.

Two years ago I came home one day and went into the bus and everything was dead. Inverters had shutdown and volts was 9-10. I only have a 30 amp circuit to plug into and with chargers and water heaters on (big mistake) the circuit breaker tripped and there she sat until I happen to go in a check things out. So I invested in an autostart for the generator by a company called Ridgecreek. It can start the generator on either volts or temperature with an adjustable run time. Since I don't keep pets in the coach I don't use the temp setting, but I do have voltage set at 12.2 and I run for two hours.

My batteries are 9 years old and need to be replaced. With a reading of 12.7 on the meter it takes me about 30 minutes to drop to 12.0V with all lights on and phantom loads. With only phantom loads ( RV style refer, LEDs, clock radio) I can get 10 hours before AGS kicks in.

My coach sat for 2 years before I got it, so there is question history on the Batteries there and then my shutdown for how long I could not say, plus they are 9 years old.

I am ready for new batteries, but do I need eight 4D's or less or would I be better off with less 8D's, AGM's of course?

GregM



My Batteries are 4D lifeline AGM's and they are at the end of their life.

[jack14r]

Truk, My watchdog has a electrical panel below the watchdog(I bet yours does too),I went into that panel and looked for 24+ volts and about 5 terminals from the left and I found it.I then tried various resistors in line with the 24+ volt wire trying to reduce the voltage by 3 volts(21+3=24)a 15K ohm resistor worked perfectly and the generator now starts at 24 volts.My digital Fluke VOM confirms that it happens at 24 volts exactly.I have wired it so if something screws up I can fix it on the road.I will be camping in Lexington,KY next week and I will report on how it goes.

[Joe Cannarozzi]

Greg I have not seen 3 inverters until now.

[truk4u]

Thanks Jack, I'll check mine out when I get back home and hope I have the same setup.

[jack14r]

I finished installing the 6 8D batteries today,Liberty has a custom cabinet that has drawers,stereo receiver,refrigerator and there is also a 42 inch flat screen in the bay.In order to get to the batteries all this as well as the panels behind this must be removed.Once everything is removed the hole is about 24X30 inches and the rack has 2 levels of three batteries,the 160+ pound batteries are not easy to install.We made a ramp out of a 2X8's and were able to push them up the hill to the rack.The cables never seem to stay untangled,and once the batteries are in and wired it is time to install all of the entertainment stuff.I learned a lot about my coach and it all works,including the outside EC.In reality this job is for a very strong man and my friend who helped me is very strong and he even said"this is not a one man job".I will be dry camping next week in Kentucky and with new Lifeline batteries and my modification to the watch dog auto start voltage I should be good to go.

[truk4u]

Jack,

I feel your pain on those Liberty batteries! I had to use a transmission jack and floor jack along with some lumber to get those bad boys out and in. I hope I never have to do another set on a Liberty.

[gmcbuffalo]

Joe my coach originally had three Todd converters in it so I think the previous owners install guys figured it was easier to do three inverters to replace them. And is I type this maybe an little extra profit from a third inverter sale.
GregM

[garyde]

:DHere is an easy way to lift and remove batteries. I replaced mine in about 2 hours on a Saturday.

5004

[jack14r]

When Liberty added the slide out TV,the slide mechanism extends under the first shelf which has reduced the shelf height by 6 inches.I only have about 2-3 inches above the batteries,which would not allow me the luxury of installing like Gary did.I will get over the soreness soon.

[jack14r]

Since my last post I have spent a week dry camping in Kentucky,my resistors worked very well but because of heat in the bay causing their value to change slightly I had to adjust the resistance and I am now using a lower value to start the generator at 23.7 volts.I have determined that about 12.4 meg ohm is approximately the right value based on about 100 degrees in the inverter bay which is where the watchdog is also located.This is an easy modification to make and so far seems to be a perfect way to fool the watchdog.

[rahangman]

Joe, I want to explore what you have described to my coach. 4ea 8d batteries for 12vdc house system with a 2500 watt xantrec Freedom Inverter. I would like to arrange for that inverter, with proper management, to operate 1 AC for the coach (Cruise Air) and also rig an auto start for the gen set so that if we are out of the bus and the dogs are in the bus, if the shorepower fails the auto gen set will keep us from having "Hot Dogs" and also allow us to use the one Cruise Air while cruisin down the Highway......what you think?

[Joe Cannarozzi]

Have you purchased an autostart yet?

Putting the source for the power to an a/c on an inverter and then making sure while you are doing that you do not overload it with other things is the easy part. (unless you have a propane fridge you absolutly can not do this with only 1 inverter)

Wiring it so you can easily and safely move that source back and forth from the main panel and inverter panel requires some engineering. I would want it to look and function like the converter installed it.

You can not leave it on the inverter while on shore or gen with only 1 2500. I have not decided how I will do mine yet. A clean instalation, convienient and failsafe is what I am looking for.

Do you have CC OTR A/C? I'm guessin not.

[Jon Wehrenberg]

Don't make the installation of an inverter more complex than need be.

To add an inverter just cut the buss bar in the 120V panel to dedicate the new short length with limited circuits to the inverter.

That way only the circuits on the short buss bar are powered by or through the inverter. Power the inverter / charger from the main portion of the buss bar. All shore or generator power to the inverter is then passed through the inverter internal transfer switch to the short section of 120V buss bar.

The AC can be the only device on that circuit if desired, and when shore or generator power is available it just passes through the inverter, while the inverter functions as a charger.

Couldn't be simpler. The hard part is routing the wires and fishing them over around and through the coach.