How To Determine Battery Life From Watt Draw

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Difference Between Amps and Amp Hours
How to Summate Work Hours on a Battery
How many Amp Hours do yous really get from a 100ah bombardment?
1. Low voltage cutting off
2. Battery Type
3. Excessive Parasitic Depict Charge per unit
4. Getting Less Than A Full Charge
Calculating Your Watt Hours
Why You Never Get all the Ability Capacity From a Battery
1. Batteries don't discharge evenly
2. Batteries are rated for 5 amps over 20 hours of time
3. Chargers may non fully charge
4. Cycle Life of a Battery Count
So how long does a 100 amp hour bombardment last?

The RV house battery can be one of the most perplexing things to effigy out when yous are trying to figure out how your motorhome or travel trailer works. It sounds elementary. You lot have, say, a 100 amp hour battery. 100 amp hours, wow! That should last for days, right? Wrong! It really isn't rocket science, simply it is math, when it comes to figuring out how long that 100 amp 60 minutes battery will actually concluding in the real world.

Difference Between Amps and Amp Hours

First off, nosotros need to understand the deviation between Amps and Amp Hours. The basic breakdown between amps and amp-hours is that amps are a unit of measurement of electrical current, while amp hours are the units of "current storage capacity."

How to Calculate Piece of work Hours on a Bombardment

The first affair we want to do is convert to watt hours. Most devices y'all employ volition take their watt usage listed on them. Y'all can catechumen Amp Hours to Watt Hours using the formula below:

Amp Hours 10 Voltage = Watt Hours

If we add in our example 100 Amp Hour bombardment size we become: 100AH Ten 12v = 1200 WH

That means that our 100 amp battery tin sustain well-nigh 1200 watts from devices for an hour or 600 watts worth of devices for two hours.

In a existent-earth example, our humidifier lists a wattage of 280w on depression and 470w on high. That means that a unmarried 100 amp hr battery tin power information technology on the low setting for 4.29 hours and for 2.six hours on loftier.

It would be bang-up if devices told usa specifically how many amps are used, and so you could merely carve up the battery chapters past full device amps. Only most devices give you a rating in Watts, which is why we need the above formula.

How many Amp Hours do you actually get from a 100ah battery?

The above formula, however, exists in a theoretical bubble. Similar most things in life, calculating how long a battery will actually terminal isn't quite as simple as knowing the formula. In that location are several factors at play that reduce that theoretical Belch Fourth dimension into real-globe usage.

Depression voltage cut off

Nigh batteries can be damaged if they are depleted below a sure level. So in that location is a low voltage cut off point that you don't want to deplete your batteries across. Yous may have a device that automatically makes the bombardment unavailable at the low voltage cut off point or yous may have to monitor your battery manually.

male customer buying the best RV battery

Battery Type

The blazon of battery you use in your RV also makes a difference in how many usable amp-hours yous actually have. Pb-acid batteries are less forgiving than lithium batteries in how far they can exist depleted, so y'all have less available amp-hours, despite the battery's amp hr rating.

A lead-acid battery isn't recommended to be tuckered below 50 percent capacity. That ways your 100 amp 60 minutes battery in existent-world applications will actually merely final around twoscore-50 amp-hours.

A LiFePO4 (lithium iron phosphate) bombardment tin be safely discharged to "0" pct capacity. You wouldn't normally discharge it that low, but you can wait well-nigh twice as many usable amp-hours as you would get from a pb-acid battery.

Excessive Parasitic Draw Rate

There are numerous appliances and devices that, even when non in agile use, have command boards or other elements that describe 12V power from your house battery. This is called a parasitic draw.

Information technology is normal, but can significantly impact how many amp hours your battery volition last betwixt charges. And don't forget about the little lights in your storage bays, booster antennas, and other devices that are piece of cake to forget virtually that can draw down the battery. It all adds upward!

Getting Less Than A Full Charge

If you don't fully accuse your battery, it's not going to provide all the amp hours that you wait. A 100 amp hour (or whatever capacity is specified) battery will come much closer to maximum efficiency if y'all keep your batteries topped off with a full charge.

Computing Your Watt Hours

There is no uncomplicated way to calculate the watt-hours you'll use on a daily basis without a battery monitoring device. To exercise so, you need to know how many watts per hour each of your devices utilise and so multiply that times how many hours per twenty-four hour period you use that device. And so you add all of the individual totals to get an guess of how many watt-hours y'all need.

Victron Energy BMV-712 Smart Battery Monitor (Grey)

Victron Energy BMV-712 Smart Battery Monitor (Greyness)

The Victron Energy BMV-712 Smart Battery Monitor (Greyness) is a high precision smart battery monitor, especially designed...
Midpoint Voltage Monitoring: The BMV-712 features an additional input which can be programmed to mensurate the voltage of...

Why You Never Get all the Power Chapters From a Battery

There are several reasons why you will never become all the power capacity from a battery that information technology is rated for.

Batteries don't discharge evenly

You don't use the exact aforementioned devices in exactly the same style for exactly the same corporeality of time day in and day out. This ways that your battery is discharged at a unlike rate depending upon how heavy the load is that you are putting on it.

The heavier the load put upon the battery, the less capacity it has, meaning information technology volition be depleted sooner than you might hope.

Batteries are rated for 5 amps over twenty hours of time

A battery's amp hour rating is based on a consistent load of 5 amps. What that means is that a 100 amp hour bombardment that has a constant load of 5 amps on it should concluding 20 hours.

That is all well and good if you were ever going to be pulling a consistent describe of v amps from the battery, but that's not how the real world works. In some instances, you will be drawing less than 5 amps per hour and sometimes more, which means the actual amount of time your battery will last is going to vary from day to solar day.

Chargers may non fully charge

Your battery may not always get a full charge. Equally mentioned earlier, batteries degrade over fourth dimension and usage, so every bit the bombardment gets older, it will not be charged fully to 100 amp hours, no affair what you do.

There are as well different types of chargers. A multi-phase charger has a more efficient way of charging; thus, keeps your battery's ability to reach a near 100-percent total charge for a long fourth dimension. A unmarried-stage charger is much more than blunt. It just doesn't have the finesse of a multi-phase charger and can sometimes shorten the life of your bombardment.

Bicycle Life of a Bombardment Count

Whether your bombardment is lead acid or lithium information technology has a finite number of cycles that information technology can be depleted and recharged. This is the bicycle life of the bombardment. Mostly, atomic number 82-acid batteries if maintained properly can exist good for a few hundred cycles. Lithium batteries on the other manus tin last thousands of cycles.

But the number of times and how securely a battery has been depleted then recharged affects how much chapters it can hold. The more than times it has been cycled, the less able it is to hold its maximum capacity.

Our Selection

Boxing Born Batteries

Meet the 100 Ah 12 V LiFePO4 Deep Cycle battery, the pinnacle of deep cycle lithium-ion battery technology for your RV!

This battery weighs only 31 pounds simply is capable of providing you lot up to 100 Amp of continuous electric current or 200 Amp of surge electric current for its whole life expectancy of 3000-5000 cycles.

It's fabricated in the United states of americaA. and comes with a 10-yr warranty.

So how long does a 100 amp 60 minutes battery last?

As y'all can come across, there is no one-size-fits-all answer to this question, because there is no i-size-fits-all way that we each utilise our RV battery on a mean solar day to day basis.

But hopefully, this helps you lot understand how the bombardment works and just what that 100 amp hr rating means in the real earth. If you can empathize that and how to decide the number of amps your various devices use, it'll get a long manner towards making your life easier on the road.

Last update on 2022-04-05 / Affiliate links / Images from Amazon Product Advertising API