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View Full Version : How long can I run things without the generator?



MystrMagic
01-20-2010, 12:42 AM
Hello everyone. I'm planning to add several batteries to my new 3914 because it seems to make sense to have additional power, but as this is my first RV I don't really know what all actually runs on batteries. Obviously the 12v lights do, and the radio, the fridge (optionally), and a couple of other things I have identified but here are my real questions.

I know the furnace uses propane but also electricity for the blower. Is it AC or DC? And I believe the air conditioner uses AC (so I assume I can't run it on batteries at all!).

If I park overnight and choose to not run the generator, can I reasonably expect to run, lets say the furnace (or furnace fan alone), along with some lighting, (without running my generator) and still have power in the morning?

In other words, what items can I run all night on one, two, three or four batteries and what should I avoid?

Wondering what your experiences are with battery power and if I can expect any practical benefit by adding extra batteries.

Would love to hear from those of you who have added batteries just what benefits/experiences you have had and do you feel it was worth the extra expense.

Thanks for all your input.

boatdoc
01-20-2010, 12:48 AM
The furnace does run on 12VDC and does eat power but with the battery bank you're talking about you won't have any problems running it all night. The trick is getting the batts charged again!! Fridge needs minimal 12VDC power as it is 110AC or gas only.

wyleyrabbit
01-20-2010, 02:13 AM
Think of batteries like big buckets of electrons. They're even rated for amp-hours to make it easier to think about. Figure out the wattage and do the math.

We have batteries rated for 220 Ah, so a 10 amp load should give me 11 hours of run time, making sure to not use the bottom half of the batteries, right? I think this is right, but if it isn't I hope someone strightens me out on this.

caissiel
01-20-2010, 07:24 AM
We can go for 3 days no problem in the summer with 2 batteries and in the fall and spring a bit less, the biggest draw on power is the furnace fan, or any fans. We usually watch the lights and drop the second light in the dual light units.

lwmcguir
01-20-2010, 07:50 AM
You can purchase a couple of 15 watt solar panels and use them as portable units very easily. This will extend your battery life a lot more than you would think. We use a quite a few solar panels to pump water and to power electric fence as well as lighting. From 5 watt stand alone to arrays and to just simple solar lights. Almost all of them perform well. The water pumps pull the most power and require the larger panels. Northern Tool has some good values as do other sites. If you are using the batteries as you charge you don't need to purchase and wire in the controller with some of the panels if you get the ones that come with clips. The controller is primarily for avoiding over charging your batteries but some cells do require them anyway.

rogerlouden
01-20-2010, 10:08 AM
It only took me one time , while boondocking, to disconnect the tow vehicles electrics from the camper while parked. It sucks to wake up in the morning to find no power in the camper and pickup. No way to get the in house generator started to charge everything up. Rehooking to the pickup will get the gen running to charge every back up. I bought a good sized battery pack to carry along now. It's not cheap, but have used it several times last year to get campers and pickups up and running.

htneighbors
01-20-2010, 11:35 AM
Water pump is also 12VDC. :)

jmgratz
01-20-2010, 11:51 AM
Polar Aire Fan is 12 volts.

smday
01-20-2010, 03:08 PM
Buy yourself really good 6 volt batteries. Get the highest amount of Reserved minutes as possible. I am putting in Discovery batteries model #EVL16A-A. They will give me 841 mins of use at 25 amp draw (RC@25amp). Here is a link to there page. http://www.discover-energy.com/productsearch?filter0=47&filter1=**ALL**&filter2=**ALL**&filter3=#more-electrical They are pricey but if you want good batteries you have to pay the price. I am also installing a 123 watt solar panel to keep them topped up all the time.

MystrMagic
01-20-2010, 03:21 PM
Thanks for the info everyone. I appreciate the help. Allow me to narrow my question down just a little.

I am familiar with watts/amps/amp hours/volts, etc., and have no problem doing the math as I have previously installed two solar power systems (with deep cycle marine batteries) for my own use (one at home and one at work). I know exactly how long I can run a 5500BTU air conditioner, lights, fans, etc. on those systems.

However I am not familiar with actual current draw from appliances and lights in an RV. There are lights all over this thing! And sometimes the fridge runs on AC, sometimes on DC & gas, etc. So I'm not really comfortable even trying to do the math and then relying on my calculations just to wake up one morning and find everything is dead.

Who has actually installed multiple batteries in your units and then tested to see if you can run various appliances/systems throughout the night?

Most of my travel will be for business purposes so I don't expect to spend more than one night in any location. I know that during the day my TV will recharge the batteries, and I also know that if I drain the RV batteries overnight I will likely drain the TV battery as well... don't want to do that!

I'm hoping to install enough batteries to be able to pull over for the night, run lights, fridge, television or stereo and perhaps a fan, without wasting gasoline for my generator. If I have to run the generator, so be it. But I'm hoping someone has already gone through this experience and can give some guidance as to what I should/shouldn't run while sleeping, and still have usable batteries in the morning.

Thanks again for whatever input you have.

smday
01-20-2010, 03:45 PM
Your tow veichle wire is to small to fully charge your batteries everyday unless your running your truck all day. With my 2 kids and 2 neices watching tv and having the lights on we still have enough juice to run the furnace all night. We just limit the amount of lights they use. If you want all the lights on, tv on, stereo going for more than 4 hours you won't make it thru the night with the furnace. If you want everything on and you don't want the solar system my suggestion is to turn on the Genset while you are watching tv and when your done the batteries will be fully charged. You need the genset or shore power anyhow to watch the tv.

Yianni
01-20-2010, 04:08 PM
I have replaced the dealer installed 12 volt battery on my last 3 trailers with 2 6 volt. on my last trailer I had 2 6's and a 12 volt with an isolator switch. On my new Cyclone I went with 4 6 volt and used a 3 way switch. I can use battery bank 1 during the night and if it runs down I can switch to #2 and have plenty of power, or I can switch all on at once. Here is a link to my thread.

//heartlandowners.org/showthread.php?t=14019

Realistically, I don't think you are going to run down 2 6 volts overnight unless you have heat running constantly and lights on and t.v. through an inverter etc. We've made it 4 nights on 2 6 volt with heater and being very careful with lights. Now with kids and a big fiver instead of a travel trailer I added the additional 6 volts because I don't want to have to sweat it anymore. I use the gen when I have to. It sure is nice to have it built in and not to have to lug a big Honda around anymore!

MystrMagic
01-20-2010, 05:28 PM
Great info! Yianni, I love your idea of creating two separate power systems with a simple switch between them. That would prevent ever having to jump start a battery. I saw your link yesterday and like what you did. But you didn't say what kind of an impact those extra batteries have made in your overall electrical use. Do you still need to run your generator a lot?

And smday, how many batteries are you using? Do you have only the factory installed or have you added any? I appreciate the comment about the TV wire being too small but I expect I will be driving a good 6 or 8 hours each day and I believe that should be enough to recharge the battery bank after each night's use don't you think?

I didn't think I could even run the furnace overnight (with my one factory installed battery) without draining the power so I haven't tried that yet. Been runing the generator all night long just to be safe.

As I said earlier, don't mind running the generator if I need to, just want to minimize the gas expense as the whole purpose of getting the Cyclone in the first place was to be able to travel at a lower cost than staying in hotels every night.

newbie
01-20-2010, 05:54 PM
Thanks for the info everyone. I appreciate the help. Allow me to narrow my question down just a little.

I am familiar with watts/amps/amp hours/volts, etc., and have no problem doing the math as I have previously installed two solar power systems (with deep cycle marine batteries) for my own use (one at home and one at work). I know exactly how long I can run a 5500BTU air conditioner, lights, fans, etc. on those systems.



That had to be quite a system to run a 55k BTU air conditioner. How many batteries do you need run a 4 ton air conditioner?

cabin fever
01-20-2010, 06:10 PM
Thanks for the info everyone. I appreciate the help. Allow me to narrow my question down just a little.

I am familiar with watts/amps/amp hours/volts, etc., and have no problem doing the math as I have previously installed two solar power systems (with deep cycle marine batteries) for my own use (one at home and one at work). I know exactly how long I can run a 5500BTU air conditioner, lights, fans, etc. on those systems.

However I am not familiar with actual current draw from appliances and lights in an RV. There are lights all over this thing! And sometimes the fridge runs on AC, sometimes on DC & gas, etc. So I'm not really comfortable even trying to do the math and then relying on my calculations just to wake up one morning and find everything is dead.

Who has actually installed multiple batteries in your units and then tested to see if you can run various appliances/systems throughout the night?

Most of my travel will be for business purposes so I don't expect to spend more than one night in any location. I know that during the day my TV will recharge the batteries, and I also know that if I drain the RV batteries overnight I will likely drain the TV battery as well... don't want to do that!

I'm hoping to install enough batteries to be able to pull over for the night, run lights, fridge, television or stereo and perhaps a fan, without wasting gasoline for my generator. If I have to run the generator, so be it. But I'm hoping someone has already gone through this experience and can give some guidance as to what I should/shouldn't run while sleeping, and still have usable batteries in the morning.

Thanks again for whatever input you have.

I also use mine for work, whenever possible I will find some place to plug in. in the summer I need it for the AC, winter for the space heater as well as the extra draw. For the other times I bought a 2000EUI Honda for the job as well as charging the rig. It is quite a bit cheaper to run that for light usage. On a hot summer night I run parallel 2k Hondas to run the AC, the house genny is under the bed= no sleep. They will run the AC for 4 hours on 2 gallons of fuel, better than nothing. There are a lot of challenges for those of us who have to keep moving even in the winter. I generally run a genny for at least 3 hours a day on the job so my batteries stay charged up and never had problem in the morning. I have 2 12 volt batteries and I have not tried to use an inverter to run the tv but I know they really use up a lot of battery.

smday
01-21-2010, 10:14 AM
Great info! Yianni, I love your idea of creating two separate power systems with a simple switch between them. That would prevent ever having to jump start a battery. I saw your link yesterday and like what you did. But you didn't say what kind of an impact those extra batteries have made in your overall electrical use. Do you still need to run your generator a lot?

And smday, how many batteries are you using? Do you have only the factory installed or have you added any? I appreciate the comment about the TV wire being too small but I expect I will be driving a good 6 or 8 hours each day and I believe that should be enough to recharge the battery bank after each night's use don't you think?

I didn't think I could even run the furnace overnight (with my one factory installed battery) without draining the power so I haven't tried that yet. Been runing the generator all night long just to be safe.

As I said earlier, don't mind running the generator if I need to, just want to minimize the gas expense as the whole purpose of getting the Cyclone in the first place was to be able to travel at a lower cost than staying in hotels every night.

Right now i just have the original 12 volt battery. i have 2-dry cell 6 volt batteries ordered for now. We decided (Battery Direct and I) to just try the 2 for now with the 123 watt solar panel. I am also installing an Xantrex inverter/ charger (RS3000) too that has an automatic generator start up just in case its really cloudy out and the solar panel doesn't charge them up. Little peice of mind and only comes on at the voltage set point you set it at.

Manke3010
01-21-2010, 04:49 PM
smday, what kinda cost am I looking at for the solar panel you got, along with that Xantrex RS3000 inverter/charger with the auto genny startup feature?

I just use a little 400w inverter now that keeps the laptop and phones charged. Running 2 12V batteries and they do alright, but I'd at least like to add Solar, if not the larger inverter/charger setup you're talking about...
Thanks for any insight...

smday
01-21-2010, 08:20 PM
smday, what kinda cost am I looking at for the solar panel you got, along with that Xantrex RS3000 inverter/charger with the auto genny startup feature?

I just use a little 400w inverter now that keeps the laptop and phones charged. Running 2 12V batteries and they do alright, but I'd at least like to add Solar, if not the larger inverter/charger setup you're talking about...
Thanks for any insight...

I sent you a PM with i am paying.

wdk450
01-22-2010, 12:31 PM
"However I am not familiar with actual current draw from appliances and lights in an RV. There are lights all over this thing! And sometimes the fridge runs on AC, sometimes on DC & gas, etc. So I'm not really comfortable even trying to do the math and then relying on my calculations just to wake up one morning and find everything is dead."

Sir:
I suggest you get a clamp on ammeter and install it around either one of the main battery cables, and then try the various lights/loads to get the data you need.

wyleyrabbit
01-22-2010, 01:57 PM
Sir:
I suggest you get a clamp on ammeter and install it around either one of the main battery cables, and then try the various lights/loads to get the data you need.

Make sure the ammeter you acquire handles DC current. I have an ammeter clamp for my multimeter, but it only works with AC.

Alternatively, most digital multimeters have an AMP setting and I think one can simply put the leads on either side of the DC fuse and measure the current going by. I'm not sure what the procedure is with this, but I'm sure someone here does, such as 2010Augusta...Alan? :)

Chris

Hamshog
01-22-2010, 06:23 PM
Here's a little article about solar power and how to do it so it really works.. Looks very interesting..

Regards, Hamshog

http://handybobsolar.wordpress.com/2009/07/22/solar-power-that-works/

htneighbors
01-22-2010, 09:31 PM
Usually, in order to measure amperage using a meter's leads, you have to put it inline and then turn on the device. Like mentioned, the simplest way is to use a clamp-on meter that checks DC amps. :)