rv battery

[donan]

i have a 5th wheel and the slide out goes out real slow, the dealer installed a small battery, i don't know what the cranking amps are fo this battery, i am thinking of changing it to a 100 crank amp battery thinking it might help move the slide out a little faster, are there any opinions re this and will it help

 

[J&JD]

i have a 5th wheel and the slide out goes out real slow, the dealer installed a small battery, i don't know what the cranking amps are fo this battery, i am thinking of changing it to a 100 crank amp battery thinking it might help move the slide out a little faster, are there any opinions re this and will it help

Always good to have as many amps available as possible. On many of our pushers with good size slides, many of us either leave the engine running or plug into shore power prior to using the slides.

 

[91CavGT]

I agree with J&JD. A small battery is just not going to be able to supply enough power for a long enough time to move the slides at a decent pace. Upgrade that small battery and they should move better.

 

[donan]

Always good to have as many amps available as possible. On many of our pushers with good size slides, many of us either leave the engine running or plug into shore power prior to using the slides.

i don't see what difference it would make if plugged into shore power because the slide out is run by the battery and the slide out motor only gets as much power as the battery can put out when it is fully charged and i think the higher the cranking amps the more power is delivered to the slide out motor, i just think a 30 cranking amp battery would struggle more to run the motor than a 100 cranking amp battery this is just what i think i could be wrong but it makes sense to me but i don't want to buy a bigger battery if it isn't going to make it better

 

[91CavGT]

Let’s compare a 30 amp/hr battery to a 100 amp/hr battery.

A 30 amp/hr battery will be able to supply 360 watts of power for an hour.

A 100 amp/hr battery will be able to supply 1200 watts of power for an hour.

However, due to these being either a flooded lead acid battery or an AGM battery, unless we want to kill the battery every time we use it, we need to decrease the capacity in half. By only using half of the battery’s capacity, it extends the life of the battery.

So now the 30 amp/hr battery can only supply 165 watts in an hour!

The 100 amp/hr battery can supply 600 watts in the same time span.

A slide on my RV has a 30 amp fuse so it probably pulls around 25 amps of current and most motors like these have a start up surge current that is needed to get the device going(kind of like an air compressor has a large surge of power needed to get the compressor moving).

So one slide is going to pull 300 watts!! So after moving your slides for just 30 minutes TOPS, on a brand new battery you will need to stop and recharge the battery. My RV has 4 slides, and sometimes I have to pull a slide back in because I didn’t get things right the first time.

So, that little 30 amp/hr battery will work, but due to its size it will be struggling (kind of like pulling a big RV with a small gas V8 vs a diesel truck). Not to mention you really don’t have any reserve power left with your 30 amp battery.


This is why EVERY RV manufacturer puts at least a 100 amp/hr battery on an RV that has a slide.

 

[donan]

Let’s compare a 30 amp/hr battery to a 100 amp/hr battery.

A 30 amp/hr battery will be able to supply 360 watts of power for an hour.

A 100 amp/hr battery will be able to supply 1200 watts of power for an hour.

However, due to these being either a flooded lead acid battery or an AGM battery, unless we want to kill the battery every time we use it, we need to decrease the capacity in half. By only using half of the battery’s capacity, it extends the life of the battery.

So now the 30 amp/hr battery can only supply 165 watts in an hour!

The 100 amp/hr battery can supply 600 watts in the same time span.

A slide on my RV has a 30 amp fuse so it probably pulls around 25 amps of current and most motors like these have a start up surge current that is needed to get the device going(kind of like an air compressor has a large surge of power needed to get the compressor moving).

So one slide is going to pull 300 watts!! So after moving your slides for just 30 minutes TOPS, on a brand new battery you will need to stop and recharge the battery. My RV has 4 slides, and sometimes I have to pull a slide back in because I didn’t get things right the first time.

So, that little 30 amp/hr battery will work, but due to its size it will be struggling (kind of like pulling a big RV with a small gas V8 vs a diesel truck). Not to mention you really don’t have any reserve power left with your 30 amp battery.


This is why EVERY RV manufacturer puts at least a 100 amp/hr battery on an RV that has a slide.

so if i understand this right the higher the cranking amps a battery has the easier it would be on the motor, so the problem with the slide out motor struggling to move the slide out could be that the battery the dealership installed might only be a 30 amp and is not supplying the needed power to fully operate the motor, so i am thinking a 100 or more amp battery might solve my problem

 

[91CavGT]

Yes, that’s correct.

 

[FL-JOE]

Here is what I have been doing with our new fiver, mainly because it has a residential frig. As we travel during the day our frig draws off the two house batteries. When we stop for the evening I unhook and auto-level the fiver. Then I always hook up to power, or if boondocking I turn on the generator, and then I run my slides out.

My reasoning behind this is I have drawn off the two house batteries all day running the frig.