Go Back   Tacoma World Forums > Tacoma Garage > Towing

Notices

Charging my RV battery

Reply
 
Thread Tools Search this Thread
Old 04-07-2010, 09:54 AM   #1
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
Charging my RV battery

I'm going to be doing a lot of dry camping this year with my pop-up camper. I will be using the truck to charge the batteries, and run the fridge while en route. When I am stopped, I am thinking I won't get more than 2 days out of my battery, less if my wife is using her hairdryer. I have 2 methods available to recharge the batteries...
1. Plug the 120V / 120V converter into the 120V inverter power in the box of the truck, idle the truck. (converter draws 360w max)
2. Plug the 7 pin wire harness, and idle the truck.

I think that method 1 will charge the battery quicker, and to a much higher level. Mostly because all voltages are regulated up this way. Method 2 is more conventional, but at idle, I doubt the alternator will produce enough voltage to charge the battery fully. I think the combination of voltage drop, and the alternator not cranking out full voltage, will be slow, and not terribly effective.
Any thoughts?
  Reply With Quote
Old 04-10-2010, 04:00 AM   #2
Senior Member
TimS is on a distinguished road
Name: Tim
Joined: Nov 2009, #26550
Location: Maine
Gender: Male
Posts: 106
TimS's Tacoma Gallery
The most important thing is to unplug your trailer from the truck so you don't discharge your truck battery. There are dual battery systems out there that have automatic seperation from the 2 batteries once the truck is shut off. I decided to just unplug my pop-up. I also have a fridge and a couple of lights and thats it.
We just recieved from Northern Tools a solar battery maintainer. $150.00. I plan to hook that up during the day to maintain the trailer battery. I hope to try it this weekend if I get some time.
  Reply With Quote
Old 04-10-2010, 08:22 AM   #3
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
The Tacoma has a relay that disconnects the charging circuit when the key is removed.
  Reply With Quote
Old 04-10-2010, 09:49 AM   #4
Senior Member
TimS is on a distinguished road
Name: Tim
Joined: Nov 2009, #26550
Location: Maine
Gender: Male
Posts: 106
TimS's Tacoma Gallery
You must have the factory tow package. I installed mine with stuff from e-trailer. There is constant 12v power to the plug on the truck.
  Reply With Quote
Old 05-17-2010, 05:47 PM   #5
Senior Member
New Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shed
 
New Mexico Taco's Avatar
Air Force: Retired
Name: Fred
Joined: Dec 2008, #11379
Location: Albuquerque
Gender: Male
Posts: 603
New Mexico Taco's Tacoma Gallery
Red face charging batteries

Just got back from a four day camping trip in cold weather and with out a generator and a 120 volt battery charger I would have been in trouble. batteries don't last more than a couple of days tops.
got to have a generator...............
  Reply With Quote
Old 05-17-2010, 06:13 PM   #6
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
I think you may have missed the point of this thread......
  Reply With Quote
Old 05-25-2010, 02:43 PM   #7
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
Quote:
Originally Posted by phantom View Post
ok i might be a tad slow but can you explain the 120v/120v into a 120v??

are you just talking about using a inverter to make 120 volts and then a battery charger??
Yes, as in plugging the 120/240 plug from the camper's charger / converter unit into the back of the truck.

Quote:
Originally Posted by phantom View Post
now is the 360 part of the watts part of the 120
i.e converts to 120 volts at 360 watts max
P=I X E so if the max output at 120 is 360 then 120 is pulling 3 amps watts
it comes out to be 30 amps on the 12 volt side if 100% efficient

there is no free lunch and when you do the elect conversions their as a good loss of energy ! so if you are using a inverter it is not as good as a alternator!
now something to think about
you have a dead battery and get a jump start, now when the jumpers are removed did you note that the charge rate was pretty hi and not a small amount just because you were at idle?

voltmeters in a car are almost useless, wish they went back to the ammeter so you could see what was going on

it was back in the generator days that you would rev it to get max output
On my truck with the scangauge, and using a voltage tester, I found out that the max voltage at the trailer battery after driving for 2 hours was 12.4 volts, (13.3@ on the scangauge) is not sufficient to charge the RV battery, (13.6 would be required to fully charge it). This is probably due to the undersized wire on the tow package, leading to a large voltage drop. This was also while running the fridge on 12v, as it would be while traveling. So I have now determined that the only way to get a full charge in a reasonable amount of time is to plug in the converter. It kicked out of bulk charge mode after about an hour. So the efficiency of the regulated 120v inverter to 120v converter is the only way to go. Not to mention, while running the inverter to charge, the truck was only consuming <2 liters of fuel per hour. Revving the engine did not noticeably change the voltage at either end.
  Reply With Quote
Old 05-25-2010, 02:55 PM   #8
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
I should note as well that I was able to get a good charge just by using the inverter / converter combo without starting the truck. My Tacoma has a large enough battery (160 mins reserve capacity), that it should be able to safely run the inverter for an hour without having to start the truck>
  Reply With Quote
Old 05-25-2010, 03:57 PM   #9
n00b
MJonAgs32 is one of the sharper tools in the shedMJonAgs32 is one of the sharper tools in the shedMJonAgs32 is one of the sharper tools in the shedMJonAgs32 is one of the sharper tools in the shedMJonAgs32 is one of the sharper tools in the shedMJonAgs32 is one of the sharper tools in the shedMJonAgs32 is one of the sharper tools in the shedMJonAgs32 is one of the sharper tools in the shedMJonAgs32 is one of the sharper tools in the shedMJonAgs32 is one of the sharper tools in the shedMJonAgs32 is one of the sharper tools in the shed
 
MJonAgs32's Avatar
Name: MJ
Joined: Apr 2009, #15949
Location: Union City, CA (SF Bay Area)
Age: 30
Gender: Dude
Posts: 8,032
MJonAgs32's Tacoma Gallery
Look into getting an oscillator. Either that or generator is the best route.
  Reply With Quote
Old 05-25-2010, 04:29 PM   #10
Senior Member
maju is one of the sharper tools in the shedmaju is one of the sharper tools in the shedmaju is one of the sharper tools in the shedmaju is one of the sharper tools in the shedmaju is one of the sharper tools in the shedmaju is one of the sharper tools in the shedmaju is one of the sharper tools in the shedmaju is one of the sharper tools in the shedmaju is one of the sharper tools in the shedmaju is one of the sharper tools in the shedmaju is one of the sharper tools in the shed
 
maju's Avatar
Navy: Retired
Joined: Apr 2010, #34673
Location: Davenport Fl
Gender: Male
Posts: 335
maju's Tacoma Gallery
I would think that you should be able to use a solar charger its not like your going to use the electric all day while camping. Youcould get a second battery and have one on the solar charger and one in use. and just swap them out periodically.

http://www.batterystuff.com/solar-chargers/
  Reply With Quote
Old 05-25-2010, 05:47 PM   #11
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
[quote=maju;1806800]I would think that you should be able to use a solar charger its not like your going to use the electric all day while camping. Youcould get a second battery and have one on the solar charger and one in use. and just swap them out periodically.

http://www.batterystuff.com/solar-chargers/[/quote]

Not worth the hassle, or the cost. @ <$2 / hour, with an approximate charge rate of 25 amps, that is hard to beat. I use too much power for anything but a very expensive solar arrangement, I have a shower that runs the pump steay when used, (for example). I drew down a 60 amp / hour battery in 2 days. As well, most of the sites in Manitoba are well treed, another reason solar won't work. Given the fact that the inverter comes with the truck, I am very happy with it.
  Reply With Quote
Old 05-25-2010, 06:01 PM   #12
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
Quote:
Originally Posted by mjonags32 View Post
Look into getting an oscillator. Either that or generator is the best route.
Why would I buy a generator, when the truck charges it just fine, the fuel consumption per amp / hour is also very reasonable.......
  Reply With Quote
Old 05-25-2010, 06:30 PM   #13
Senior Member
New Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shedNew Mexico Taco is one of the sharper tools in the shed
 
New Mexico Taco's Avatar
Air Force: Retired
Name: Fred
Joined: Dec 2008, #11379
Location: Albuquerque
Gender: Male
Posts: 603
New Mexico Taco's Tacoma Gallery
Cool

No I didn't miss the point of your thread I just thought that you would be staying out longer. Does your popup have any accessories? (lights furnace)
Just trying to help like every body else.
Attached Thumbnails
Charging my RV battery-img_0866.jpg  
  Reply With Quote
Old 05-26-2010, 04:59 PM   #14
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
I was meaning to say that the point of the thread was about using the truck to charge, and avoiding the generator, solar or what ever other methods are available, given that the truck has ample charging capacity, I see no reason to lug around extra equipment, that's all.

Anyhow, our camper has a shower, furnace, interior / exterior lights, 1500 watt inverter, ventilation fan, etc.. We rarely stay in one spot for more than 3 days, so we will be charging through the 7pin while towing, and through the inverter when needed while stopped. I
  Reply With Quote
Old 08-02-2010, 12:13 PM   #15
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
Dry camped for 2 weeks, used the inverter plug in the box to charge the battery for appoximately 4 hours a day. I would charge in the morning for 1 hour idleing, one hour truck turned off. Same in the evening.
I should note the my Tacoma sucks for charging while towing, I always arrived with a cold fridge, and a almost completely dead battery. Stupid truck only sends 13.4 volts to the charging pin on the 7 pin. Useless. 14 volts is the minimum required at the connector to have adequate supply, very disapointing considering the cost of the towing package. I understand the battery will not fully charge this was, but after 14 hours of continuous driving, the battery should be higher than 11.7 volts (dead).
  Reply With Quote
Old 08-02-2010, 01:05 PM   #16
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
In the interest of solving this problem, I have ordered a DC to DC booster, no dead battery, and no need to use the inverter. Hopefully....
http://www.powerstream.com/dc2.htm?nowritefs
  Reply With Quote
Old 08-02-2010, 08:24 PM   #17
Senior Member
skytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shed
 
skytower's Avatar
Navy: Gunners Mate
Name: Dave
Joined: Jun 2010, #38505
Location: virginia
Gender: Male
Posts: 3,185
skytower's Tacoma Gallery
Sounds to me like you need a stronger alternator, or a second one. It's quite alot to ask from a alternator to run that much equipment.
If you're not getting the right voltage at the trailer, you may need a larger gauge of wire.
As for the booster, I would think that it will put an even larger load on your alternator. Usually those are for protecting sensitive electronics, right?
  Reply With Quote
Old 08-02-2010, 08:57 PM   #18
Lord of Tomfoolery
genxer36 is one of the sharper tools in the shedgenxer36 is one of the sharper tools in the shedgenxer36 is one of the sharper tools in the shedgenxer36 is one of the sharper tools in the shedgenxer36 is one of the sharper tools in the shedgenxer36 is one of the sharper tools in the shedgenxer36 is one of the sharper tools in the shedgenxer36 is one of the sharper tools in the shedgenxer36 is one of the sharper tools in the shedgenxer36 is one of the sharper tools in the shedgenxer36 is one of the sharper tools in the shed
 
genxer36's Avatar
Name: Sean
Joined: Nov 2007, #3442
Location: Bethlehem,GA
Age: 46
Gender: Dude
Posts: 10,660
genxer36's Tacoma Gallery
How to Wire a Car/Truck to Charge a Camper Battery
http://www.ehow.com/how_6738763_wire...r-battery.html
  Reply With Quote
Old 08-03-2010, 11:44 AM   #19
Banned
Isthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shedIsthatahemi is one of the sharper tools in the shed
Joined: Apr 2009, #16582
Gender: Male
Posts: 1,160
Isthatahemi's Tacoma Gallery
Tha Tacoma only puts out around 13.4 volts under normal conditions. Not enough to supply a fridge and charge the battery at the same time. Heavier gauge wiring will help, but the dc dc booster will solve the issue completely, whereas thicker wire only helps a little, again because the Taco runs 13.3ish, as opposed to every other vehicle I have worked on that runs 13.6 - 14.4.
  Reply With Quote
Old 08-03-2010, 11:48 AM   #20
Senior Member
skytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shedskytower is one of the sharper tools in the shed
 
skytower's Avatar
Navy: Gunners Mate
Name: Dave
Joined: Jun 2010, #38505
Location: virginia
Gender: Male
Posts: 3,185
skytower's Tacoma Gallery
The voltage is only half the equation. Your alternator can only push so many amps at its rated voltage. Try to pull more and it will eventually fry.
The fact that your battery is dead after driving with all the accessories attached is enough evidence for me to say you're overloading the alternator.
  Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
HO alternator/Dual Battery/Battery Separator/"Big 3 Upgrade chazjb 1st Gen. Tacomas 13 04-09-2012 05:13 AM
Battery (Charging System) Light plasticjeep Technical Chat 5 04-04-2012 05:12 AM
Charging while towing campthewestcoast Towing 2 02-14-2011 06:02 AM
Towing RV that has its own battery TimS Towing 10 03-06-2010 11:59 AM
Battery Not Charging shaff33 2nd Gen. Tacomas 14 11-03-2009 04:48 PM


Copyright © 2014 Tacoma Forum. Tacoma World is not owned by, or affiliated with Toyota Motor Corporation.