RV.Net Open Roads Forum: Tech Issues: Watts Help Needed.

RV Blog

  |  

RV Sales

  |  

Campgrounds

  |  

RV Parks

  |  

RV Club

  |  

RV Buyers Guide

  |  

Roadside Assistance

  |  

Extended Service Plan

  |  

RV Travel Assistance

  |  

RV Credit Card

  |  

RV Loans

Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tech Issues

Open Roads Forum  >  Tech Issues

 > Watts Help Needed.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 6  
Next
Sponsored By:
jbfoster

California

New Member

Joined: 08/18/2008

View Profile


Offline
Posted: 05/21/19 10:08pm Link  |  Quote  |  Print  |  Notify Moderator

I am trying to figure out how long a battery will last. I have Googled it and read a few sites but I still have a few questions.

I have a small TV that I plugged into my Kill a Watt meter. That shows 22 watts. I plan on using a 1000w inverter hooked to one 12v battery. I havn't purchased a battery yet so i'm not sure how many AH I will have to work with.

At 12v that would be 1.8 amps.
at 124v that would be .18 amps.

Which amp usage would I use, the 1.8 amps or .18 amps?

Thank You
Jim

elivi8

Langley

Full Member

Joined: 07/05/2011

View Profile


Offline
Posted: 05/21/19 10:23pm Link  |  Quote  |  Print  |  Notify Moderator

A standard 12V battery will have around 90 amps and you can only use about half of that so 45 amps else you will shorten the life of the battery.

You would be using the 1.8A number at 12V.

Ryan


2012 F-150 EcoBoost, Max Trailer Tow
2011 Cougar 26BHSWE

time2roll

Southern California

Senior Member

Joined: 03/21/2005

View Profile



Good Sam RV Club Member


Posted: 05/21/19 10:33pm Link  |  Quote  |  Print  |  Notify Moderator

I would round up to 3 amps and call it 15 hours.


2001 F150 SuperCrew
2006 Keystone Springdale 249FWBHLS
675w Solar pictures back up

jbfoster

California

New Member

Joined: 08/18/2008

View Profile


Offline
Posted: 05/21/19 10:47pm Link  |  Quote  |  Print  |  Notify Moderator

That will be plenty I think. Pretty much all I will be doing is the TV and maybe charging two cell phones. I'm also getting the Westinghouse iGen1200 generator. It's a 1000 watt and 1200 watt peak. I'm guessing the max amp battery charger would be 8 amps this generator could handle. I would probably get a 5 amp battery charger and then run the generator 2 to 3 hours or less a day to top of the battery. Almost forgot the 650 watt coffee maker to make a cup or two a day. That shouldn't be to much at 600 watts for about 3 minutes a cup.

Jim

pianotuna

Regina, SK, Canada

Senior Member

Joined: 12/18/2004

View Profile


Offline
Posted: 05/21/19 11:21pm Link  |  Quote  |  Print  |  Notify Moderator

Divide watts by 10 to get amps @ 12 volts.

Divide amp-hours of capacity by 2 to get usable amp-hours.


Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp hours of AGM in two battery banks 12 volt batteries, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.

MrWizard

Traveling

Moderator

Joined: 06/27/2004

View Profile



Posted: 05/21/19 11:54pm Link  |  Quote  |  Print  |  Notify Moderator

don't confuse DC amps and AC amps

a 5 amp charge at 13v+ is only 65 watts

8 amps at 120v input too a battery charger or converter is 960 watts

you want a charger/converter between 30 and 45 amps DC charge

500 to 700 watts of charging

5 to 10 amps of charging will take days to recharge/replace what you use


Radiate The Happy
....

Connected using Verizon and AT&T
1997 F53 Bounder 36s


MEXICOWANDERER

las peƱas, michoacan, mexico

Senior Member

Joined: 06/01/2007

View Profile


Offline
Posted: 05/22/19 12:50am Link  |  Quote  |  Print  |  Notify Moderator

Inverters at low percentage of potential percentage of power are sooey-sooey pig-pig hogs of power. You are forgetting the 20% Charge Efficiency Factorial. 20% vigorish the battery charges for loans. Do all your VA calculations then add the 30% minimum replenishment energy premium.

I wish it was more efficient.

wa8yxm

Wherever I happen to park

Senior Member

Joined: 07/04/2006

View Profile


Offline
Posted: 05/22/19 06:40am Link  |  Quote  |  Print  |  Notify Moderator

YOu need to add an amp for the inverter overhead

But when you say 1 12 volt battery.... Well that can be anything from a couple amp hours to over a thousand. Just so you know

Minimum recommended for a 1,000 watt inverter is 200 amp hours.


Home is where I park it.
Kenwood TS-2000 housed in a 2005 Damon Intruder 377


Airdaile

On The Road

Senior Member

Joined: 01/28/2019

View Profile



Posted: 05/22/19 07:19am Link  |  Quote  |  Print  |  Notify Moderator

You want to look at a battery's reserve capacity rather than amp hours.





prichardson

Lafayette, La

Senior Member

Joined: 10/31/2006

View Profile





Offline
Posted: 05/22/19 07:25am Link  |  Quote  |  Print  |  Notify Moderator

Forget the coffee maker when on battery power only.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 6  
Next

Open Roads Forum  >  Tech Issues

 > Watts Help Needed.
Search:   Advanced Search

Search only in Tech Issues


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:

© 2019 CWI, Inc. © 2019 Good Sam Enterprises, LLC. All Rights Reserved. | Terms of Use | PRIVACY POLICY | YOUR PRIVACY RIGHTS