New to 12V DC and have a question.

[Speedygoss]

I am new to the whole Travel trailer thing and am defiantly getting schooled in 12V DC.

Please read this and let me know if I am still doing something wrong.

Long story short my TT didn't come with a battery cut off switch and every time I went to use it I assume between the constantly lit stereo display and the smoke/monoxide detectors it was always dead. I decided to add a second battery so I went to Walmart and bought the biggest baddest deep cycle battery they had and wired it with the existing battery parallel. I charged them both up with at a 2 amp rate. I added a battery tender Jr. (.75A) to the batteries in hopes to maintain a float charge when in storage. (Next use of trailer batteries were dead dead!) I have since realized you cant mix not only a battery of a different size but its recommended to use the exact same size, make, model and age battery due to different charge and discharge rate.

Fast forward to today.

First I added a cut off switch between the batteries and the trailer for when its in storage.
I have purchased 2 brand new Interstate SRM-24 batteries. (this is the make and model the TT came with new)
Without the batteries installed I have charged the batteries individually to full charge at a 2amp rate.
In an attempt to simulate the batteries in storage and "cut off from the trailer" I wired them parallel and added the battery tender Jr. hoping it will continuously "float charge the batteries"

My first question is:

1.) Will a battery tender Jr. @ a charge rate of only .75A maintain 2 of these specific batteries wired parallel?

2.) Will the battery tender listed above be able to charge and maintain these batteries from a less than full charge. (AKA if i bring the TT back from a trip and the batteries are at say 30% or 50% or 80% charge will it be able over time to bring them up and maintain in storage.

Thanks,
Eric.

 

[cookie]

I am not real familiar with the Prowler, but I think that it should have a power converter/charger on board.
If this is that case, when your rig is in storage, instead of hooking up a battery charger, just plug in the rig shore cord.
This will maintain your batteries.
You can verify if you have a converter/charger by calling Heartland.
877-262-8032 / 574-262-8030

Peace
Dave

 

[Speedygoss]

Thanks Dave, I will look into that.

Does everything else look like the correct train of thought?

 

[TedS]

If your onboard converter/charger is plugged in and working you do not need another battery. It should keep your battery or batteries charged. Is your trailer plugged in to power when in storage?

If you have no onboard converter/charger the battery tender should charge your battery or batteries. Where do you get power for the battery tender? You could plug the trailer shore power into the same source and not use the battery tender. The battery tender would work for charging the batteries at home if you remove the batteries during trailer storage.

Two batteries always give you more up time than one.

 

[cookie]

If the battery tender would be able to bring you back to full charge, it would take forever.
They are meant to maintain a fully charged battery.
A trickle charger normally charges at 2 amps, so charging two of them at .75amps would be a challenge for the Battery Tender Jr.
Another thing is that if you are traveling your truck alternator will be charging the batteries.
Do not use the disconnect when towing. Your RV needs 12 volts for the breakaway switch to work.
But if you can plug in at storage and you have an onboard converter, the Tender Jr will not be needed.

Peace
Dave

 

[cookie]

Sorry about the lag time in my reply. I got distracted in the middle of it.
Ted pretty much said what I wanted to say.....and did.

Peace
Dave

 

[brianharrison]

My first question is:

1.) Will a battery tender Jr. @ a charge rate of only .75A maintain 2 of these specific batteries wired parallel?

2.) Will the battery tender listed above be able to charge and maintain these batteries from a less than full charge. (AKA if i bring the TT back from a trip and the batteries are at say 30% or 50% or 80% charge will it be able over time to bring them up and maintain in storage.

Thanks,
Eric.

1. yes
2. yes, but it will take a really long time - I estimate 3-5 days from 50%, maybe longer.

As mentioned, best bet is to use the on board converter (120 to 12V) to keep the batteries full state of charge. If you have the Progressive Dynamics 9100 series, the charge wizard pendant turns it into a 4 stage intelligent charger, if you already have the 9200 series, it is a 4 stage charger already. See Progressives web page here.

Visit the HOM manuals page for some good info on batteries and charging systems.

Here is an external page with good info, 12V Side of Life.

Brian

EDIT: I type slower than Dave!

 

[pegmikef]

FYI all of the Prowlers have a 45 Amp 12 volt converter according to the HL site.

 

[hoefler]

Without a disconnect, the parasitic draw is greater than the output of the battery tenders. In other words, the tenders cannot keep up and the parasitic draws win. If you have power to plug the battery tender in, you should be plugging the coach in instead.

 

[wdk450]

Speedygoss:
If you can plug in during storage your charger/converter is your best battery charging/maintaining device. Especially the Progessive Dynamics PD9200 series.

If you can't plug in, I noticed you are in Arizona, prime solar panel country. No cord or outlet needed, and after initial costs free power.

 

[Bob&Patty]

However you keep the batteries charged, you must check and maintain the water levels in the batteries unless they are a sealed battery. The battery disconnect must be in the on position to charge from shore power.