Boondocking Newbies

[Steve P]

Can anyone recommend a website or article with the basics for boondocking in a Class A?  

We "think" I know the basics... We have no solar.  We don't have an Auto Generator Start, so we have to manage power consumption ourselves.  Fridge and heat and water heater will run on Propane.  Turn off the water heater after showers. 

Inverter will switch from inverting to charging when the generator is running, but does it charge the house batteries exclusively, or does the BIRD govern what is charged?  We know to unplug chargers and such from the outlets.  Don't run the microwave unless the genny is running.  If batteries show 10.5-11 volts in the inverter, should we start the Generator to charge them, or wait (until what voltage?)?  The Generator starts using the chassis batteries, right?

Most lights are flourescent or incandescent, not LED, so we will try to minimize their use.  We don't know how parasitic the Macerator toilets (2) are.  We will switch off the motion-sensing porch light.

Other than the above, some of which might be wrong, we are pretty uninformed.  Any and all help would be appreciated.

Thanks, 

Steve

 

[Ivan K]

You wait way too long to charge the batteries,  I would not let my flooded go past 12.0V true voltage with no major load, it takes too long to get them back, besides their lifetime. No clue about the toilets but you should really consider LED lights at least where you most use them. Shunt current monitor would tell you where you are wasting power. I know some say that solar is expensive but diesel is too, if you get serious. There's no magic to boondocking, it's all about not using more than you can replenish with what you have.

[cbr046]

I bought a pair of these and use them in % mode.  https://www.amazon.com/gp/product/B07V8S9PCX/  One for the house and one for the chassis.  I connected them to the Intellitec battery test switch for convenience.  You won't get "precise" voltages but you'll have an idea where your batteries are without memorizing voltage/percentage charts.  When I get to 50% I crank up the generator for an hour or so. 

You'll learn how far to stretch your juice and when to crank up the generator. 

- bob

 

[jacwjames]

I installed a BMV712 battery shunt monitor last year.  I bought the one that has the monitor but I seldom use it, I rely on the phone/bluetooth to monitor the batteries. 

This provides a true state of charge of the batteries but also provides a lot on information.  I've been traveling in CO and it has been getting pretty cool at night but I don't turn the furnace on until the AM just before I get up.  It was 50F in the LR when I turned on the furnace.   I monitored the battery voltage but also I watched the amp draw.  With the furnace running I was using ~20-21 amps and when the furnace shut off ~13 amps.  During the time the furnace ran to bring the temp from 50 to 57F I used 2% of battery, down to 70%. 

I have been comparing the BMV712 voltage and the Xantrex, the Xantrex is not consistent at all.  About the only time they are similar is after I have driven the coach all day or run the generator for cooling until batteries are 100%.  The numbers soon diverge with the BMV712 showing higher voltage.   So I really don't rely on my Xantrex to maintain the battery voltage.   With the Bluetooth capability I can check periodically during the night.  When I was boon docking in pretty cold weather my system heat was working frequently to keep wet bay warm, this is the 300W cube heater and ~150 watt of tank heating pads that are controlled by their own thermostats so hard to tell what the actual draw is. 

Like Ivan, I don't let my batteries get below 12 volts. 

Edited October 24, 2023 by jacwjames

[Tom Cherry]

5 minutes ago, jacwjames said:

I installed a BMV712 battery shunt monitor last year.  I bought the one that has the monitor but I seldom use it, I rely on the phone/bluetooth to monitor the batteries. 

This provides a true state of charge of the batteries but also provides a lot on information.  I've been traveling in CO and it has been getting pretty cool at night but I don't turn the furnace on until the AM just before I get up.  It was 50F in the LR when I turned on the furnace.   I monitored the battery voltage but also I watched the amp draw.  With the furnace running I was using ~20-21 amps and when the furnace shut off ~13 amps.  During the time the furnace ran to bring the temp from 50 to 57F I used 2% of battery, down to 70%. 

I have been comparing the BMV712 voltage and the Xantrex, the Xantrex is not consistent at all.  About the only time they are similar is after I have driven the coach all day or run the generator for cooling until batteries are 100%.  The numbers soon diverge with the BMV712 showing higher voltage.   So I really don't rely on my Xantrex to maintain the battery voltage.   With the Bluetooth capability I can check periodically during the night.  When I was boon docking in pretty cold weather my system heat was working frequently to keep wet bay warm, this is the 300W cube heater and ~150 watt of tank heating pads that are controlled by their own thermostats so hard to tell what the actual draw is. 

Like Ivan, I don't let my batteries get below 12 volts. 

Ah, yes.  But have you calibrated or compared or tested it?  The real test is to run the exercise test….3 cycles.  Then find the real SOC after you remove the surface charge.  Then let the batteries sit, disconnect off, jumpers removed….and sit for 30 minutes.  Then measure the SOC and VDC and compare to the Trojan chart.  The chart tells you the real SOC. Interpolate to the nearest whole number.  Then compare to what the instrument says.  That is the only real way….otherwise… the reading may be false.  OR correct!.  But yet, folks are purchasing BMK’s and Shunt systems and such and putting total trust into a device that may have not been tested or validated.

I really want to know if they work and how accurate they are….looking for real data.  They may be 100% or off by 10 or more %….but we don’t know.

All my reading and talking to Magnum and Trojan and testing shows that the recovery voltage or SG after being discharged, is the REAL discharged SOC.  THEREFORE, the load voltage, is usually 0.1 -0.2  VDC lower than the recovery.  But, each bank or brand may be different.  The only way is to measure the load voltage at say, 11.8 VDC and see if the recovery voltage or SOC is close to 12.0 or 50% SOC.

I hope you accept the challenge.  I would like to know how accurate they are.  Magnum says that their remote meters are only +/- 10%…so how do you trust them?

 

[jacwjames]

12 minutes ago, Tom Cherry said:

Ah, yes.  But have you calibrated or compared or tested it?  The real test is to run the exercise test….3 cycles.  Then find the real SOC after you remove the surface charge.  Then let the batteries sit, disconnect off, jumpers removed….and sit for 30 minutes.  Then measure the SOC and VDC and compare to the Trojan chart.  The chart tells you the real SOC. Interpolate to the nearest whole number.  Then compare to what the instrument says.  That is the only real way….otherwise… the reading may be false.  OR correct!.  But yet, folks are purchasing BMK’s and Shunt systems and such and putting total trust into a device that may have not been tested or validated.

I really want to know if they work and how accurate they are….looking for real data.  They may be 100% or off by 10 or more %….but we don’t know.

All my reading and talking to Magnum and Trojan and testing shows that the recovery voltage or SG after being discharged, is the REAL discharged SOC.  THEREFORE, the load voltage, is usually 0.1 -0.2  VDC lower than the recovery.  But, each bank or brand may be different.  The only way is to measure the load voltage at say, 11.8 VDC and see if the recovery voltage or SOC is close to 12.0 or 50% SOC.

I hope you accept the challenge.  I would like to know how accurate they are.  Magnum says that their remote meters are only +/- 10%…so how do you trust them?

 

When I get home I intend to see what's going on. 

The saying is "trust but verify".  I usually don't trust anything until I can confirm. 

[Tom Cherry]

3 minutes ago, jacwjames said:

When I get home I intend to see what's going on. 

The saying is "trust but verify".  I usually don't trust anything until I can confirm. 

You took the bait.  I started to use the TR line.  I really want to know if all this electronic shunt wizardry works….

Thanks….

[TW Racing]

We dry camp about 95% of the time. We run our generator for two hrs every morning and nite. Never had an issue during a two week trip. The big power robber is the heater when it gets down into the 20s, but have never gotten below 12 volts. 

[waterskier_1]

1 hour ago, Tom Cherry said:

Ah, yes.  But have you calibrated or compared or tested it?  The real test is to run the exercise test….3 cycles.  Then find the real SOC after you remove the surface charge.  Then let the batteries sit, disconnect off, jumpers removed….and sit for 30 minutes.  Then measure the SOC and VDC and compare to the Trojan chart.  The chart tells you the real SOC. Interpolate to the nearest whole number.  Then compare to what the instrument says.  That is the only real way….otherwise… the reading may be false.  OR correct!.  But yet, folks are purchasing BMK’s and Shunt systems and such and putting total trust into a device that may have not been tested or validated.

I really want to know if they work and how accurate they are….looking for real data.  They may be 100% or off by 10 or more %….but we don’t know.

All my reading and talking to Magnum and Trojan and testing shows that the recovery voltage or SG after being discharged, is the REAL discharged SOC.  THEREFORE, the load voltage, is usually 0.1 -0.2  VDC lower than the recovery.  But, each bank or brand may be different.  The only way is to measure the load voltage at say, 11.8 VDC and see if the recovery voltage or SOC is close to 12.0 or 50% SOC.

I hope you accept the challenge.  I would like to know how accurate they are.  Magnum says that their remote meters are only +/- 10%…so how do you trust them?

 

Tom, I think you are conflating SOC (State of Charge, measured in percent of the battery capacity) and Battery Voltage.  There is no "surface SOC".  You seem to be implying that the charts that Trojan or other Lead Acid (Flooded Lead Acid or AGM) publish to help the user estimate the SOC by voltage as the Standard by which SOC is measured.  A true Battery Monitor for SOC (not to be confused by the Battery Voltage Monitor Bob H. linked to in his post above, measures electron flow into and out of the battery.  Ok, it really measures the electron flow through the shut, which presumably is connected to the battery.  It don't know or care about voltage, type of battery chemistry (Lead Acid, Lithium, etc.).  For it to present the net count of electrons, it does need to know the battery capacity.  This is where any calibration takes place.  It may know the number of electrons, but if it doesn't know the total number, it can't tell the State of Charge (SOC) or % of charge.  Think of a water flow meter, it knows how much water was used, but it can't tell you how much you have left or what percentage you have left, unless you tell it the size of the supply tank.  

No, what you have mentioned above does come into play in determining the Capacity of the battery.  For most batteries, this is done by discharging the battery at a know level (amps) for a know period of time (minutes or hours) and then using calibrated equipment to recharge the battery fully.  That is where Surface Charge takes effect.  Most readers don't bother unless there is reason for questioning.  So, most people enter the Amp-Hour rating the manufacturer gives.  But this deteriorates over time, and if accuracy is required, needs to be reassessed periodically.  Again, most readers don't do this.  It is true that the shunt might not be perfectly accurate, but the accuracy is magnitudes greater than other elements in the system.  And who need to measure their SOC to within 0.01% accuracy?  Give me 2% - 5% and I'll call that good.  We aren't designing space or weapon systems here.  I dare say that the shunt is 10 times more accurate than a field battery capacity test.  Additionally, the battery capacity will change depending on the rate of discharge.  For LiFePO4 batteries, it is recommended NOT to use voltage to determine the SOC, since the LiFePO4 batteries hold their voltage fairly constant down to about 15% SOC.  This is the main reason these new Battery Monitors are becoming so prevalent (along with cost decreases).   

[waterskier_1]

3 hours ago, Steve P said:

Can anyone recommend a website or article with the basics for boondocking in a Class A?  

We "think" I know the basics... We have no solar.  We don't have an Auto Generator Start, so we have to manage power consumption ourselves.  Fridge and heat and water heater will run on Propane.  Turn off the water heater after showers. 

Inverter will switch from inverting to charging when the generator is running, but does it charge the house batteries exclusively, or does the BIRD govern what is charged?  We know to unplug chargers and such from the outlets.  Don't run the microwave unless the genny is running.  If batteries show 10.5-11 volts in the inverter, should we start the Generator to charge them, or wait (until what voltage?)?  The Generator starts using the chassis batteries, right?

Most lights are flourescent or incandescent, not LED, so we will try to minimize their use.  We don't know how parasitic the Macerator toilets (2) are.  We will switch off the motion-sensing porch light.

Other than the above, some of which might be wrong, we are pretty uninformed.  Any and all help would be appreciated.

Thanks, 

Steve

 

You have thought things through, but you should never let your batteries drop below 12.0 (some say 12.2) volts.  That is the "average" voltage for Lead Acid batteries to be deemed 50% discharged.  Discharging below that will significantly decrease battery life.  Your use of 10.5 - 11.0 volts is a dead battery, likely to not be recovered. 

Without look up wiring diagrams, I don't know if your Knight has a BIRD.  If it doesn, and it is functioning (all my comments assume everything is functioning as it should) then your Chassis batteries will be charged when on Shore (Gen) power.  If you are not sure if you have a BIRD, ask and someone will check for you.

Monaco was not consistent (and there are many that will argue both ways) with which battery bank the generator starts.  I recommend the Chassis battery, so when you do get the house batteries low, the generator will still start.   

I have AGS (Automatic Generator Start), but rarely does it get used.  Now, in my system, which is not Magnum (it's all Victron equipment) AGS mean starting the generator when battery conditions signal it to do so.  I have a separate ATS (Auto Temperature Start) which I understand some Magnum Inverters have incorporated in the overall AGS terminology.  I have never even tested my ATS, as I have never been somewhere I felt that was critical.  I don't often stay where heat would be a problem for a few hours if I lost Shore Power (it is mostly used for when Shore Power fails, and that kills the A/Cs, the generator will start and continue powering the A/Cs).  I look at AGS as a lazy man's safety.  I believe in actively participating in the management of my energy usage, and as such, will check the battery conditions before the need to fire up the gen.  I know it works because I left my coach for some body work and they had it inside their shop for over a week.  Normally this isn't a problem because I have solar, but that doesn't work inside.  I received notifications that the generator was periodically starting.  The shop didn't notice until they had it in their paint booth and came in and the booth was full of exhaust.  I look at AGS like overdraft protection on a checking account.  I know what I have in my bank, and what I spend, so I have no need for overdraft protection.  But not everyone has the same attention to details, and sometimes "stuff happens".  

Since you already own the coach, go live in it.  Disconnect from Shore Power and see how long the batteries last under "normal" usage.  If you can't make it overnight, you need to address either your "normal" or you need additional (or maybe replacement) batteries.  This is something you can do, even in when your at home.  Watch the battery usage.  I dry camp with several others with Monaco's for weeks.  Many have solar, but some don't, and they do just fine.  The fire up the generator in the morning when they get up, cook breakfast, and let it run a couple hours.  Then again at dinner for an hour or two.  If it's cold and the will be using the furnace overnight, they will run the gen about an hour before retiring to top off the batteries.  This is for Lead Acid batteries.  Oh, and don't try to recharge Lead Acid batteries to 100% on the generator.  The last 15% can take HOURS - not worth the fuel.  Generally I suggest to shut down the gen when the charger goes into Float Mode, unless you are using it for something besides charging batteries.  You'll get a lot more bang for your buck by running the gen 3 times a day versus trying to recharge to 100%  Of the group still laugh at me for running my generator, twice a day, for 8+ hours trying to get the last 3-5% back in the batteries.  Another thing, if you use CPAP, turn off the humidifier.  My CPAP draws less than an amp without the humidifier.  It is rated at 4.5 Amps with the humidifier.  That 45 Amps @ 12.5 VDC!   Of course, the humidifier doesn't run 100% of the time, but it will save if you are having issues making it overnight without running the generator.  If you are not using your inverter (no need to have 110 VAC) turning off the Inverter will save 4+ Amps, the plus being whatever else it is powering.  Before I upgraded to LiFePO4 batteries, I could save over 20 Amps overnight by killing the inverter.  That is because of all the "stuff" I have running, and that was easier than running around unplugging things (like TVs, Dish Receivers, WiFi Routers, Cell Boosters, and lots of other things) and then re-plugging them in in the morning.  I can't answer your question about the macerator toilets, but I expect it is high when used, but for short durations.  I suspect the "parasitic" draw would be insignificant.  

I've seen many articles from different RV groups (FMCA. Escapees, etc) and others, but don't have a direct cite for them.  

Bottom Line:  Try testing how things go when you have Shore Power (so you don't have to fire up the gen if the batteries get weak) before you attempt extended dry-camping.  

  -Rick N.

[1nolaguy]

Steve, welcome on board. All of the information given above is excellent.  In addition you might watch some Youtube vlogs on the subject. There are many on boone docking (BD) but only a few on BD with a Class A. In particular you might check out Our Next Exit and Today Is Someday.

Based on personal experience I found switch from Lead Acid (LA) to Lithium (LFP) or LiFePO4) batteries was important. More important than solar. LFP has dropped a lot in the last year or two so it is now cost effective. Many promote Battle Born, which are great batteries at about $1000 per 100 Ahr but there are now dependable other options including SOK at about $600 for the same 100 AHr or even LiTime for about $350 for the same 100 AHr. I recently added two TWV 100 AHr mini LFP batteries for $500 delivered.  While these lower priced batteries may have shorter warranties or fewer cycles the difference in cost off sets that, especially if you are not full time and BD all the time. LFP adds capacity while reducing weight. There is one catch,  LFP batteries have a much flatter state of charge (SOC) so will go from usable voltage to insufficient voltage in a heart beat. Power will cut off in a instant when your voltage drops too low rather than gradually as with LA. On the other hand LFP batteries charge much quicker than LA so while to charge you LFP batteries may take 2-4 hours of running the generator it my take 8 to 24 hours to charge your LAs depending on capacity of your system.

1) My recommendation, if you choose LFP, is to definitely install a battery shunt monitor so you can see your actual SOC. Second is to consider adding a gen auto start. Most generators use the house batteries for start power so when the batteries are too low it is also too late to start your generator.

2) Motor homes are the most like stick and brick homes when it comes to RVing. As a result there are many of parasitic electrical draws, in including your inverter. If your RV is like mine (Cheetah 40 DHT) the inverter has to be on for most of the 110v outlets to work. There are a few that require gen. or to be plugged in.

3) When looking at BD consider weather and fuel cost. Batteries will not run your A/Cs so unless you love the heat and or humidity take the weather where you are going into consideration. Some folks love BD for being remote and alone in the quiet and in nature. For some its about saving money (no camping fees). For the latter group you need to keep in mind fuel cost. A generator on a class A uses 1/3rd or more gal of fuel per hour. If you are diesel that is $4-6 per gallon so you can easily use $20-72 of fuel a day running you generator.

After 6 years of RVing we now only BD in cooler month or northern geography whether the weather is dry and temps are below 70. Remember that 70 outside can mid 80s of hoter inside if your windows are closed and the fans/vents are closed. Other than the occasional over night lot-docking (Walmart/ Cracker Barrel) when in route or at at Harvest Host we tend to use camp grounds. We spend much of our time in the coastal south of the US so for us weather is a major factor.

Hope this all helps in your decision process.

 

[Gweedo]

If you boondock a lot like we do 7-10 days at a time in the desert, I would suggest a small generator.  I had two Honda's 2200 I paralleled (one just died after several years and couldn't even tell you how many hours it had), but I only run one all day and all night.  We use 1-gallon of gas every 6-7 hours.  I have a 6-gallon feed tank so I never have to worry about it running out of fuel at night.  One genny keeps everything running, fridge, Batt charger etc with zero issues because there is no catching up.  When I paralleled two they ran the micro as well.  You can pick up a Predator at Harbor Freight way cheaper and larger especially when on sale.   In the evening when the grandkids bombard us for dinner I run the coach genny for a couple hours because of the electric cooking appliances etc.  

Happy boondocking!!!!

[Tom Cherry]

13 hours ago, Steve P said:

Can anyone recommend a website or article with the basics for boondocking in a Class A?  

We "think" I know the basics... We have no solar.  We don't have an Auto Generator Start, so we have to manage power consumption ourselves.  Fridge and heat and water heater will run on Propane.  Turn off the water heater after showers. 

Inverter will switch from inverting to charging when the generator is running, but does it charge the house batteries exclusively, or does the BIRD govern what is charged?  We know to unplug chargers and such from the outlets.  Don't run the microwave unless the genny is running.  If batteries show 10.5-11 volts in the inverter, should we start the Generator to charge them, or wait (until what voltage?)?  The Generator starts using the chassis batteries, right?

Most lights are flourescent or incandescent, not LED, so we will try to minimize their use.  We don't know how parasitic the Macerator toilets (2) are.  We will switch off the motion-sensing porch light.

Other than the above, some of which might be wrong, we are pretty uninformed.  Any and all help would be appreciated.

Thanks, 

Steve

 

Well now, you've got a LOT of information.  There is NO STANDARD or best way....whatever works for you as well as your needs and the restrictions on where you boondock.  I was asked to write up a paper on batteries....as I often offered advice....so here is the link.

FWIW....and this is MY opinion, however, it is also the opinion of a LOT of seasoned members.  Batteries are like "fine ladies".....and one's tastes will dictate....but also they have some needs, which can become quite high....  SO...This is MY TAKE....  and others may not agree or they have special situations.

Flooded cell batteries, especially the high end or the GOLD STANDARD (Trojan T-105) are the BEST and MOST COST EFFECTIVE battery.  They don't cost that much more than the next level Interstates.  They last a lot longer than the "brands" sold by Batteries Plus.  We have many members, one in particular, that is going on 10 years on a bank.  We all, to get that life, have an accurate hydrometer and VOM and exercise them at least twice a year.  We use Water Miser caps (Amazon) and rarely add more than an ounce to each sell when we test and exercise. I like a wooden gauge...which is outlined, as my old eyes are excellent for a 78 YO Male.  BUT, having a simple dip stick to get the electrolyte level about 60% of the way between the bottom of the well and the plates is easy.  Trojan NOW has a well designed well with a FILL TO HERE mark.  THEY LEARNED.

AGM's are often a second choice.  However, if you GOOF or have an equipment failure, the results can be costly.  They are NOT as robust as the Flooded cells.  YES, they are used on higher end coaches and such and commercial units.  BUT, if you don't exercise them and keep your Inverter charger set for the RIGHT profile...then they can fail prematurely.  We often have topics where "I bought AGM's and they failed quicker than my old flooded..." and the cause is usually lack of exercising and or not knowing HOW to set up or properly charge them.  WHATEVER YOU DO....Trojan recommends NOT Equalizing any BATTERY...Flooded as the last resort.. but IF you equalize AGM's, say good bye and have your credit card ready....not tomorrow, but within a year or two.

Lithium.  Wonderful technology and evolving. Problem is, that unless you have a newer inverter, you may NOT be able to properly charge them. Most of our Lithium experts recommend specific DC to DC chargers and do NOT let the Lithiums charge from the OEM or replacement inverter/chargers.  THAT is a gross and maybe incorrect overview....but for my needs....I don't do that much dry camping....and am satisfied from a performance and price (value) with my Trojans.  IF you need this, then PLEASE DO A LOT OF READING and SEARCHING HERE...we DO have experts...

NOW...the RULE of thumb... and this was and has been a topic at a lot of our Gatherings....regarding Boondocking and especially conversions to residential refrigerators is this.  Convert to ALL LED overheads.  Fluorescents are OK...but some will turn off one fixture if there are 3 in the living area.  Put the home entertainment systems on a power (Surge) strip and TURN THEM OFF THERE....standby sucks up juice. With a normal, good set of 4 flooded cells, you need to only run the Genny 3 or so hours every 24 hours.  The icemaker should be cut off and use the "LOW or ENERGY EFFICIENCY" mode if the res refer has that.  

The rest....  just one comment.  I know folks that do a lot of tailgating.  Purchasing two Honda 2200's would be almost $3500 with the parallel hookups....and the off brands are usually good. Your needs and the surrounding rules or environment should be taken into account.  The cost of running is about the same.  The 7.5 or 8.0 Onan uses, typically, 0.5 GPM.  YES, it will be higher when you are on full charge.  So, figure 2 gallons per 3 hours of charging.  Then compare that to around 3 gallons for the Honda's.  

NOW, if you need FULL TIME POWER and can't exist off of inverted, then that is a different scenario.  Many folks have solar farms on their roofs.  They camp where they can, usually, be in full sun.  But, the cost of them adds up.  

So, it is a dollar evaluation versus needs and looking at alternatives.

I have dry camped for several extended periods at festivals and in NP's, one of which has ODD hours and very restrictive conditions....like no more than 3 hours but you can do it twice a day. I added the Magnum "Auxillary" start harness ($15) and a simple DC 24 hour programmable timer ($25) and started my Genny for 1.5 hours twice a day....and we were STILL free to go out and enjoy the park....so that was a good "investment and solution" for me.

As to the AGS and run down....read the paper.  Generally speaking, folks make a mistake or misunderstand the charts.  When you allow the AGS to start the Genny, you are usually under a load.  The "Under Load" voltage is usually 0.1 to 0.2 VDC LOWER than the RECOVERY or when there is NO LOAD (relatively speaking) on the bank.  So, in reality....you should be able to set the AGS to say 11.8 or so....then the AGS kicks in and you recharge.  Typically 3 to 3.5 hours for a 4 battery bank.  Setting it at 12 VDC actually hurts, from a long range standpoint, the life of a battery.  Better to run the batteries down to 12.0....RECOVERY, not AGS setting which is 50%.  Some say even 11.9 RECOVERY...which would, typically, equate to 11.7 on the AGS.  NEVER lower....as you might NOT have enough juice to crank the genny.

Hope this helps.  I also hope no one takes offense at my summations of the alternatives....this is my understanding and folks that have special needs or such are really creative and knowledgeable....

 

[cbr046]

Same here (Gweedo's comment).  I run a Harbor Freight Predator 3500 because I don't like the noise & rumble of the house generator.  Go ahead, call me a snob!  But then I haul a trailer to put the Predator in so space isn't an issue.  When I get to my campsite (cow pasture) I haul out the Predator, hook it up and run off the inverter until the batteries get low, then start the Predator (unless I need the microwave).  This is usually not until the next day.

I first started out with a Honda 2000 but when I arrived it would max out the Honda doing a "force charge" on the batteries.  This would happen every time I connect to shore power (ie Honda) and I can't find a way to go straight to float charging.  The batts are at full charge when I arrive (Xantrex 458 inverter). 

The Predator 3500 is 100 lbs.  The Honda 2200 is a manageable 60 lbs, and there's a "special" gas cap where you can siphon from a larger 5 gal container. 

You can pick up multiple sizes of Predators (2000, 3500, 5000?) through Facebook Marketplace from scratch & dent and "lightly used" sellers.  Sounds sketchy, I know, but that's where mine came from and I would do it again saving hundreds.  Turns out you can buy at Harbor Freight, use it for a weekend, then turn it back in for a full no-questions-asked refund.  They can't sell it so they offload them by the pallet load.  I did my best to research the seller (local, American name, long FB history) and literally met the guy at a storage facility where he had them stacked up in a 10x10.  Mine had zero hours on it (scratched somewhere).   

- snobby bob

Edited October 24, 2023 by cbr046

[1nolaguy]

31 minutes ago, cbr046 said:

Same here (Gweedo's comment).  I run a Harbor Freight Predator 3500 because I don't like the noise & rumble of the house generator.  Go ahead, call me a snob!  But then I haul a trailer to put the Predator in so space isn't an issue.  When I get to my campsite (cow pasture) I haul out the Predator, hook it up and run off the inverter until the batteries get low, then start the Predator (unless I need the microwave).  This is usually not until the next day.

I first started out with a Honda 2000 but when I arrived it would max out the Honda doing a "force charge" on the batteries.  This would happen every time I connect to shore power (ie Honda) and I can't find a way to go straight to float charging.  The batts are at full charge when I arrive (Xantrex 458 inverter). 

The Predator 3500 is 100 lbs.  The Honda 2200 is a manageable 60 lbs, and there's a "special" gas cap where you can siphon from a larger 5 gal container. 

You can pick up multiple sizes of Predators (2000, 3500, 5000?) through Facebook Marketplace from scratch & dent and "lightly used" sellers.  Sounds sketchy, I know, but that's where mine came from and I would do it again saving hundreds.  Turns out you can buy at Harbor Freight, use it for a weekend, then turn it back in for a full no-questions-asked refund.  They can't sell it so they offload them by the pallet load.  I did my best to research the seller (local, American name, long FB history) and literally met the guy at a storage facility where he had them stacked up in a 10x10.  Mine had zero hours on it (scratched somewhere).   

- snobby bob

Bob, you might try an inline 12v to 12 v DC to DC converter to limit what is going to the batteries. I would install it at the batteries (bay). That would leave you something for other purposes, even with a 2kw generator.

41 minutes ago, Tom Cherry said:

Well now, you've got a LOT of information.  There is NO STANDARD or best way....whatever works for you as well as your needs and the restrictions on where you boondock.  I was asked to write up a paper on batteries....as I often offered advice....so here is the link.

FWIW....and this is MY opinion, however, it is also the opinion of a LOT of seasoned members.  Batteries are like "fine ladies".....and one's tastes will dictate....but also they have some needs, which can become quite high....  SO...This is MY TAKE....  and others may not agree or they have special situations.

Flooded cell batteries, especially the high end or the GOLD STANDARD (Trojan T-105) are the BEST and MOST COST EFFECTIVE battery.  They don't cost that much more than the next level Interstates.  They last a lot longer than the "brands" sold by Batteries Plus.  We have many members, one in particular, that is going on 10 years on a bank.  We all, to get that life, have an accurate hydrometer and VOM and exercise them at least twice a year.  We use Water Miser caps (Amazon) and rarely add more than an ounce to each sell when we test and exercise. I like a wooden gauge...which is outlined, as my old eyes are excellent for a 78 YO Male.  BUT, having a simple dip stick to get the electrolyte level about 60% of the way between the bottom of the well and the plates is easy.  Trojan NOW has a well designed well with a FILL TO HERE mark.  THEY LEARNED.

AGM's are often a second choice.  However, if you GOOF or have an equipment failure, the results can be costly.  They are NOT as robust as the Flooded cells.  YES, they are used on higher end coaches and such and commercial units.  BUT, if you don't exercise them and keep your Inverter charger set for the RIGHT profile...then they can fail prematurely.  We often have topics where "I bought AGM's and they failed quicker than my old flooded..." and the cause is usually lack of exercising and or not knowing HOW to set up or properly charge them.  WHATEVER YOU DO....Trojan recommends NOT Equalizing any BATTERY...Flooded as the last resort.. but IF you equalize AGM's, say good bye and have your credit card ready....not tomorrow, but within a year or two.

Lithium.  Wonderful technology and evolving. Problem is, that unless you have a newer inverter, you may NOT be able to properly charge them. Most of our Lithium experts recommend specific DC to DC chargers and do NOT let the Lithiums charge from the OEM or replacement inverter/chargers.  THAT is a gross and maybe incorrect overview....but for my needs....I don't do that much dry camping....and am satisfied from a performance and price (value) with my Trojans.  IF you need this, then PLEASE DO A LOT OF READING and SEARCHING HERE...we DO have experts...

NOW...the RULE of thumb... and this was and has been a topic at a lot of our Gatherings....regarding Boondocking and especially conversions to residential refrigerators is this.  Convert to ALL LED overheads.  Fluorescents are OK...but some will turn off one fixture if there are 3 in the living area.  Put the home entertainment systems on a power (Surge) strip and TURN THEM OFF THERE....standby sucks up juice. With a normal, good set of 4 flooded cells, you need to only run the Genny 3 or so hours every 24 hours.  The icemaker should be cut off and use the "LOW or ENERGY EFFICIENCY" mode if the res refer has that.  

The rest....  just one comment.  I know folks that do a lot of tailgating.  Purchasing two Honda 2200's would be almost $3500 with the parallel hookups....and the off brands are usually good. Your needs and the surrounding rules or environment should be taken into account.  The cost of running is about the same.  The 7.5 or 8.0 Onan uses, typically, 0.5 GPM.  YES, it will be higher when you are on full charge.  So, figure 2 gallons per 3 hours of charging.  Then compare that to around 3 gallons for the Honda's.  

NOW, if you need FULL TIME POWER and can't exist off of inverted, then that is a different scenario.  Many folks have solar farms on their roofs.  They camp where they can, usually, be in full sun.  But, the cost of them adds up.  

So, it is a dollar evaluation versus needs and looking at alternatives.

I have dry camped for several extended periods at festivals and in NP's, one of which has ODD hours and very restrictive conditions....like no more than 3 hours but you can do it twice a day. I added the Magnum "Auxillary" start harness ($15) and a simple DC 24 hour programmable timer ($25) and started my Genny for 1.5 hours twice a day....and we were STILL free to go out and enjoy the park....so that was a good "investment and solution" for me.

As to the AGS and run down....read the paper.  Generally speaking, folks make a mistake or misunderstand the charts.  When you allow the AGS to start the Genny, you are usually under a load.  The "Under Load" voltage is usually 0.1 to 0.2 VDC LOWER than the RECOVERY or when there is NO LOAD (relatively speaking) on the bank.  So, in reality....you should be able to set the AGS to say 11.8 or so....then the AGS kicks in and you recharge.  Typically 3 to 3.5 hours for a 4 battery bank.  Setting it at 12 VDC actually hurts, from a long range standpoint, the life of a battery.  Better to run the batteries down to 12.0....RECOVERY, not AGS setting which is 50%.  Some say even 11.9 RECOVERY...which would, typically, equate to 11.7 on the AGS.  NEVER lower....as you might NOT have enough juice to crank the genny.

Hope this helps.  I also hope no one takes offense at my summations of the alternatives....this is my understanding and folks that have special needs or such are really creative and knowledgeable....

 

Note about comment concerning older inverters, according to Xantrex (I had this conversation with their Tech Specialist) the Freedom 485 will charge LPO batteries but because I run a residential fridge and other electronics (ie CPAP, etc.) I invested in a new pure sine inverter (several makes including Xantrex, Magna, Growatt, Aims, etc) have models that can easily replace you Freedom 485 if needed.

[cbr046]

Regarding Trojan batteries . . . . heard an interview with a guy from Optima Batteries.  Turns out they use highly purified lead in their batteries and that makes all the difference in capacity and longevity.  They just earned a $90M military contract (so they must be good?).  Optimas are AGM only (which I don't recommend for coach batteries) and make Trojan prices look like Walmart $400 vs $200. 

- bob

[Ivan K]

I for one can't stand generator sound for long no matter how low, just the constant hum in a place that should be quiet drives me nuts. We spend most our time outside unlike most others we have met. We mostly run the genny for cooling while on the move.  For that reason, our relatively small ~1.2kw solar is well worth it and we manage to run what we need including outside TV and Starlink all day long. We recently spent few days with TimAZ and his fulltiming friends, we were the only ones running the genny for maybe half an hour a day to make coffee. I felt bad for being the only noisy neighbor in the group. Cloudy days might be a different story but not much of a problem out west. These people know how to boondock full time and invested in the equipment to do that. Moving with the weather is a big part of it.

[96 EVO]

15 hours ago, Steve P said:

   The Generator starts using the chassis batteries, right?

 

 

Your coach being the same MY as mine, I'm going to say there's a better chance your gen get's it's starting power from the house batteries.

Even more reason to follow Ivan's advice and not run your house bank below 12.0v (without a load), or they may not turn over your gen!

[cbr046]

There's always the Boost Switch but for a $100 Gooloo GP4000 you can have the spare of all spares - https://www.amazon.com/GOOLOO-GP4000-Starter-SuperSafe-Portable/dp/B09HJH1S41/

Todd gave it a good review on Project Farms - https://www.youtube.com/watch?v=bMXyoIBJyJA&t=356s

- b

[Tom Cherry]

16 minutes ago, cbr046 said:

Regarding Trojan batteries . . . . heard an interview with a guy from Optima Batteries.  Turns out they use highly purified lead in their batteries and that makes all the difference in capacity and longevity.  They just earned a $90M military contract (so they must be good?).  Optimas are AGM only (which I don't recommend for coach batteries) and make Trojan prices look like Walmart $400 vs $200. 

- bob

I used to frequent a LOT of Vette sites.  The one I trusted the most was like this one.  THEY KNEW OF WHAT THEY POSTED.  There was a running debate over AGM's and such as a lot of us don't use our Vettes as "Daily Drivers".  I also got to know the local lead tech at the Interstate distributor and he knew his stuff and had the equipment to salvage batteries.  

I never got any GOOD feeling or proof....and this is MY READING....MY CALL.... on the advantages of AGM's for increased battery life or performance on the Vette site.  There are two major, highly advertised. battery manufacturers..  OPTIMA and some other one.  Very rarely did anyone on the Vette sites quote how long and how great the Optima's were....quite the contrary.... the gist was... Failed about 6 months after the warranty ran out.  I did do a bit of googling....just to verify.  When I went to the OPTIMA site, there is a pop up.  ACCEPT OUR COOKIES.  OK....NOW wait a minute.  I had to TURN ON THE "DO NOT SELL MY INFORMATION" block.  THANKS but NO THANKS....

AGM's have their place....funny thing, the Local Interstate distributor said that they pulled the AGM's out of their fleet of 10 or so "delivery" trucks....did not last.

My wife's ATS has an original GM AGM....and it has been maintained....as in I put the maintainer on it and never leave it sitting in the garage for more than a week or so....certainly NOT months on end.  SO, I will replace it with the SAME GM AGM.  BUT, my C7 Vette has the same OEM GM battery....and it starts great and I have tested the drawdown voltage when it was started after a few days.  Again, I drive it at least once a week....but due to the normal ills of being 78, there are times, when physical limitations prevent that.  SO, I put on the maintainer....

I DO know, from monitoring and reading 98% of ALL posts here that AGM's are popular....but we have more questions, as well as buyer's remorse about them....as the HYPE was NEVER HAVE TO FOOL WITH THAT MESS AGAIN.  OPPS. you MUST exercise and maintain an AGM.  Trojan PLAINLY States that about their AGM line.

So...old fashioned.  Yes.  We have a LOT of smart old fashioned members.  IF the MH came with AGM and the electrical systems were SPECIFICALLY designed....like the Provosts and the ForeTravels and the upper ends ($750K MSRP) coaches....then, by ALL MEANS....keep the AGM's.

BUT, our Magnums were specifically designed for Wet Cells...and YES, Magnum has improved the setup for AGM and is working on Lithium.  SO....I have wet cell charging....and wet cell batteries will I continue to buy....and my Trojan's are now 8 years old...exercised. 

The going rate, from doing a little CraigsList searching in other locales is under $175 or so for the T-105.  Shop wisely...  I paid $150 for mine about 3 years ago....and $125 in 2013 when I bought my first set....

 

[Tom Cherry]

4 minutes ago, cbr046 said:

There's always the Boost Switch but for a $100 Gooloo GP4000 you can have the spare of all spares - https://www.amazon.com/GOOLOO-GP4000-Starter-SuperSafe-Portable/dp/B09HJH1S41/

Todd gave it a good review on Project Farms - https://www.youtube.com/watch?v=bMXyoIBJyJA&t=356s

- b

AH YES... I bought one.  A buddy, not on the forum also said it was great....and most of the Car Dealerships have one when a salesman can't start a used car and there is a hot prospect.

BUT....THERE IS A CATCH.  REAL WORLD HERE...so be advised.

I helped my GS find a replacement vehicle as his "ride" looked like it was run through a crusher.  THANK GOD FOR THE SUBARU cage and air bags.

Found a Mazda.  Bought it from my favorite big dealership and the manager, a friend, ran it back through his "shop".  They do an hour to 2 hour inspection of EVERY trade-in.  Odds are.....60% go to auction.  This one passed....but I wanted a "Gee, any RUST" and one of their top techs spent 2 hours as a courtesy.

They had put in a new battery.

Five days later.....IT WON'T START.  Researched.  That particular year had a Neutral Safety Start Switch that had "hard rubber" tabs....so when it went into park, the shifter knob (console shift), moves to the left....spring loaded.  My GS had had a "funny thing" happen and forgot to tell his GD of the situation.  OK....lets get this puppy started.  Popped out the Capacitance or ELECTRONIC MARVEL.  NADA.  NOTHING.  So, back to Jumper cables.  The battery was flat run down....dead....  It took my Yukon's alternator about 5 minutes to put on enough surface charge for the Mazda to start.  

BTW... I did find out about the Neutral Safety Start switch issue and there was a REVISED one...has PLASTIC Tabs.....  The Dealership didn't hesitate.  They bought the $100 switch and added the  3 hours labor and replaced the battery that had been "run down"...

The MORAL OF THE STORY.  The battery jump packs are for batteries that do NOT have enough power to start...but are NOT TOTALLY DEAD.  Same is true for our MH.

IF the Chassis or House runs down totally as in DEAD....then forget the Jump Pack.  I carry mine in the ATS as it has the oldest battery.

SO...this is a follow-up.....USER report.  

YES.. I will carry it when we travel....but I also have a set of Jumpers for the MH....ALWAYS turn off the DISCONNECTS FIRST, BOTH BANK's Switches.  THEN hook up the TOAD or Jumper the House to the Chassis...  THEN turn on the disconnect switches...  THEN start the Genny and let the genny put a little or a LOT of charge on the Chassis or VICE VERSA....start the engine... THEN crank the device (Genny or Diesel mill) that had the weak battery.  

NOW repeat and....  TURN OFF BOTH engines and turn OFF BOTH disconnects in the MH.  THEN pull the jumpers...  Disconnects ON...  Proceed to crank.

This is ESPECIALLY important on the CCM chassis MPX systems....so I chose to point that out....

[Steve P]

I'm drowning in info... I guess it would have been good to mention that I have 4 AGM batteries for the house, and two larger ones for the chassis.  I also have a Magnum inverter, and the Intellic EMS remote.  If the EMS has an AGM setting, that's what it's on... I can't remember, but I did check it last year.

[96 EVO]

Same rules apply!

There's really little difference between AGM and flooded lead acid batteries!

[Steve P]

Clearly, the first few nights, I am not going to sleep well (due to frequent battery checks!).

[96 EVO]

As long as your batteries are in decent condition, and your charger is set properly, you will likely be fine.

Run your gen a couple of hours in the morning, and a couple of hours in the evening.

One thing I always have to remember to do before boondocking is make sure the 'Shore' setting on the Magnum remote is set to 30-40A.

I lower mine down to 5-10A when parked at home on 30A power.

There's no point in burning fuel running your gen, only to have your battery charging throttled back by a low charger setting! 

Edited October 24, 2023 by 96 EVO