Charging 6v golf cart batteries?

[engineer40]

Hello all! I'm new to campers but have been enjoying learning about my new (used) Viking 10ft popup truck bed camper. It did not come with any house batteries. After some research and looking at my budget for now, I purchased 2 6v golf cart batteries. I have them wired in series for 12v output. They are working as expected.

As far as I can tell, my camper does not automatically recharged the batteries when I'm plugged into shore power. I have a decent work around. There is a house plug in in the same cabinet as I have the batteries. I have a spare smart charger that I plan to wire directly to the battery terminals so it automatically charges them when I plug into shore power. I've been using this battery charger for a few years and it's never overcharged anything.

Since I have 2 6v batteries wired in series I'll need to connect the charger to the positive battery terminal on 1 battery, and to the negative battery terminal on the 2nd battery. I believe that way both batteries are being charged equally at the same time. If I do this, do I have the charger set to 12v/2amp? I'm assuming I do... But my charger also has a setting for 6v/4amp and since the batteries are technically 6v, it has me questioning my thinking here. I appreciate any clarify you all can provide. Thanks!

[pianotuna]

engineer40,

Most RV's come with a charger known as a 'converter'. Yours may be unplugged, or not functioning correctly.

Try this:

disconnect the battery bank. Now turn on a light in the RV (plugged into shore power). If it works--then the charging path to the battery bank is faulty.

[Grit_dog]

engineer40 wrote:
Thank you. Thinking through the scenario, if I'm plugged into shore power (since my batteries are charging), wouldn't anything I use in my camper be using shore power and not the battery bank? So my batteries would be doing nothing except charging?

Or am I thinking about this incorrectly? I'm new to campers.

I'm willing to buy a new/better charger if it would make my camping life easier in some way. Thoughts?

No, only things that are AC power, like a microwave or airconditioner will run straight off shore (AC) power. All the DC components like fridge, waterpump, lights, funrace fan etc still run off of DC current and they get their current from the battery, or a converter (battery charger/DC power supply "converted" from AC shore power). Since you don't appear to have a converter, you're only pulling from the battery.
So, no, the little battery maintainer you have won't do much against the Amp draw.

What you really want is a converter rather than a bigger charger. Wire it in and be done. If you're on a budget, though a big battery charger (20-30amp), $100 min, will be cheaper than a good converter, $200min. And a smaller(10a), but way better than you have charger will be cheap.
Amp for amp, same charge rating will do the same thing, except the converter will give you full power to your camper even if the battery is dead.

Volt meter, get a digital multimeter. Anything will work, quality depends how valuable and how long you intend to keep it.
And 99% of what you use it for will be checking for voltage and continuity. Quality/accuracy is not as important unless you're actually reading current or resistance and need to know actual values. But a cheap one will be, well, cheap, and a decent one will be durable and reliable. I coughed up for a good one 25 years ago and it still works, only needs new batteries every 5-10 years, and it's durable.
IF you want an amp-meter, (I've been repairing and maintianing all my vehicles for my whole life and only had a few times I wish I had one, campers included) then get a clamp on amp meter.

[valhalla360]

engineer40 wrote:
Thank you. Thinking through the scenario, if I'm plugged into shore power (since my batteries are charging), wouldn't anything I use in my camper be using shore power and not the battery bank? So my batteries would be doing nothing except charging?

Or am I thinking about this incorrectly? I'm new to campers.

I'm willing to buy a new/better charger if it would make my camping life easier in some way. Thoughts?

Sounds more like a trickle charger intended to maintain an unused battery (they will self discharge over time even with no loads on them)

2 amps at 12v = 24 watts. Assuming it's running at 2amps 24/7, that's 576 watt-hours per day. (it's not exactly correct as charging is actually at slightly higher voltages but that's offset by not being 100% efficient, etc... but close enough to get a rough idea).

So let's say:
- 3 - 12w light bulbs for 4 hours = 144 watt-hours
- 0.5hr of water pump at 100w = 50watt-hours
- 4hr of furnace fan at 100w = 400 watt hours

That basically gets you to 600watt-hours which means you are using more than you put into the battery.

Do you want to charge your cell phones? Run a 12v fan? If there is an electronic control board on the fridge? Radio/TV? Those will all draw more power...and this is a simple low consumption rig. Does it have electric jacks/stabilizers?

Add an inverter to make coffee or run a microwave and it goes up dramatically.

If you are only out for a single night and you start with a fully charged battery, you can probably make it work if you are careful about power consumption but it's marginal.

[Gjac]

What is the max amp output on your charger? For my 2 6v GC batteries I charge at 40 amps, when batteries are 50% depleted. You can buy a portable 40 amp charger for about $100 or so. Depending how your trailer is wired, and the age of the trailer most will draw from the battery when plugged into shore power and the battery acts like a filter. When you are plugged into shore power check the voltage at your batteries you may already have a built in charger. If so your voltage should read 13 volts plus. Most trailers and MH's have a built in charger. Maybe someone on here is more familiar with your trailer and give you a more detailed answer.

[Lwiddis]

Have you considered an adequate solar system?

[engineer40]

Thank you. Thinking through the scenario, if I'm plugged into shore power (since my batteries are charging), wouldn't anything I use in my camper be using shore power and not the battery bank? So my batteries would be doing nothing except charging?

Or am I thinking about this incorrectly? I'm new to campers.

I'm willing to buy a new/better charger if it would make my camping life easier in some way. Thoughts?

[jy]

If you are camping somewhere and charging at a 2 amp rate,and you are using 10 amps your batteries will be slowly dying.

[engineer40]

valhalla360 wrote:

After that, it basically charges like any 12v battery. Just be aware that 2amps won't allow you to use much 12v power. Modern RV charging systems are typically in the 30-60amp range.

Thank you. Can you explain what you mean by your AMP statement? I assumed that being 2amps would just make it take longer to charge. But sounds like it's more detrimental to my battery bank than long charging times?

What benefit would a 30amp capable charger provide me? Thank you!

[CA_Traveler]

You are charging it correctly, 12V charge for a 12V battery or 2 6V in series. The 6V setting can be used to charge a single 6V battery.

Any basic VOM will be useful and one that can measue amps are usually limited to say 10A and can be helpful. Further up the food chain is a clampon ammeter that makes measuring amps so much easier and for much higher amps. Make sure you get one that measures DC amps, many for electricans measure only AC amps and labeled DC since they can measure DC volts.

[valhalla360]

Connect to the positive on battery 1 and negative on battery 2. If you put a volt meter on the terminals, they should show roughly 12.X volts if you have the correct combination (if you get the wrong combination, it should show 0 volts).

After that, it basically charges like any 12v battery. Just be aware that 2amps won't allow you to use much 12v power. Modern RV charging systems are typically in the 30-60amp range.

Any multimeter will do. It is nice to get one with a clamp on amp meter, so you don't have disconnect anything to check on amperage but you don't need a $300 meter.

[engineer40]

Secondary question... I'm going to buy a volt meter. Are there any specific features of a Volt meter or multi meter that I should look for directly related to troubleshooting RV electrical? Example, I think it would be nice if I could tell if there was a current draw on the battery bank during certain uses. That's just one example, but I am a new camper owner, so I'm sure there are things I haven't thought of yet. Thank you!

[Grit_dog]

You now have 1 - 12V battery, just in 2 separate boxes. You’re correct in using the 12V setting.
Now, if it only has a 2A setting, this won’t be of much use while actively using the batteries and trying to maintain a charge.
Presume your camper doesn’t have a converter from this post and your other post.
I would find a larger charger.