Deltran battery tender Junior

[Ron]

Been informed that the Deltran battery tender Junior is an excellent tool to keep the battery fully charged in our RV's especially when the RV is not used often.

Wondering if there are any pros and cons?

Ron

[markopolo]

The Battery Tender brand is often recommended on forums as being good. I have two of the BatteryMINDer brand myself.

If you have a newer Roadtrek I don't think you need a battery tender though. The Tripp-Lite inverter/charger for the house battery coupled with the under-the-hood Sure Power Battery Separator for the chassis battery should keep all of your batteries nicely maintained.

The '04 Roadtrek that I owned had a basic Hehr Power Systems isolator under-the-hood - not a Sure Power Battery Separator - so it did not allow the chassis battery to be maintained by the Tripp-Lite inverter/charger. I used a BatteryMINDer to keep the Roadtrek (Chevy) chassis battery charged because there was a parasitic drain that would discharge the chassis battery in two or three weeks if I didn't use the van. Keyless entry systems, compasses, in-dash radios etc. all continually consume a little bit of current.

With a newer Roadtrek (and maybe other Class B Brands) just plugging into grid power should keep all batteries charged if everything is wired up right and the parts are all working.

Test it with a volt meter or multimeter. If the van has been plugged in for a day or more check the voltage at the house battery and the chassis battery. They should be the same and at at least 13.1 volts to 13.6 volts on the high side. Some "smart" chargers periodically put out a boost charge so don't be to alarmed if you see up to 14.4 volts for 15 minutes or so. If the house and chassis battery voltages are not the same then your system is not setup up to maintain all batteries when plugged in.

You don't want to maintain batteries at higher than 13.6 volts though. Even that voltage is on the high side in my opinion. Older chargers in vans constantly supplied 13.6 volts or 13.8 volts and that is not good for long term maintenance. My current van is plugged in all the time at home. All batteries are joined together by a manual selector switch in my situation. I have a digital display on my inverter that I turn on to check the voltage whenever I go into the van just to keep an eye on things.

For anyone with a "smart" charger in their van and simple isolator under the hood you can manually join the two banks using a jumper wire to allow the "smart" charger to maintain the house and chassis battery banks. See this: http://www.classbforum.com/phpBB2/vi...2&t=453&p=1038 I don't recommend it simply because it easy to forget the jumper wire under the hood. Put a reminder tag on the van steering wheel to remind you to always remove the jumper before starting the van and driving off. The jumper is handy to have as you could use your house batteries and/or generator to give your van a jump start if the chassis battery went dead while camping.

Every RVer should have a way to measure battery voltage. If you are plugged in for a day or more and see 13.1 or 13.2 volts at all batteries for newer Class B's then that is ideal. You should at least see that voltage at the house batteries for maintenance when plugged in.

[Ron]

If a Battery Tender Junior is being used, connected to the chassis battery of a 2010 RoadTrek would it also be charging the 2 house batteries?

Ron

[markopolo]

I'd say maybe it depends on the output voltage of the Battery Tender Junior.

Sure Power Battery Separator
MODEL 1315-200
This unit will activate only
when either the Main or
Auxiliary Battery System
exceeds 13.2 volts.

Note: either the Main or Auxiliary

That tells me that the Battery Separator joins the two battery banks when either side exceeds 13.2 volts The 13.2 volts is the key - what is the output voltage of the Battery Tender Junior?
They show 12 volts on their site but it would be higher than that. I saw another site that showed 13.2 v output for the Battery Tender Junior.

Maybe end them an email to find out the actual output voltage.

Also - to anyone reading this - apply that info to the second post in this topic. The Tripp-Lite output would need to be at least 13.2 volts for the Battery Separator to join the two battery banks.

[Ron]

Mark,

Where the 2 house batteries on my 2010 RoadTrek are the 12 Volt Golf Batteries is it possible to use the Deltran Battery Tender Junior to charge the 2 house batteries as they equal a total of 24 volts?

Instead of connecting the RoadTrek to AC to keep the house batteries charged, if using the Battery Tender Junior to charge the house batteries would be best, if it can be done.

Ron

[markopolo]

I merged these two topics together.

Your Roadtrek is 12 volts. No doubt about it.
Two 6 volt batteries connected in series gives you 12 volts. With series connections only the voltage increases. The amp hour capacity remains the same.

Yes, you can charge two series connected 6 volt batteries with a 12 volt charger.

If you wanted to use the Tripp-Lite inverter/charger in your Roadtrek for charging the batteries at home you would need a 30A to 15A adapter plug (if you don't already have one).



The key to using either the Tripp-Lite inverter/charger or the Battery Tender Junior will be the charger output voltage. It needs to be at least 13.2 volts to activate the under-the-hood Sure Power Battery Separator.

Don't buy a 24 volt charger - your Roadtrek house system is 12 volts and the chassis battery is also 12 volts.

[Ron]

Excellent information Mark.

Thanks,

Ron