Choosing a Charger and Amp hour meter

Hi Everyone,

I recently purchased a 06 2720 and the deka group 24 battery is not holding a charge. I am looking to replace the battery. I expect limited use spring / fall furnace running at a national park once a year and maybe one or two weekend trips during summer I think I will replace with one or two deka wet cell deep cycle group 27 batteries. I have done the research and it would be nice to have a rolls or lifeline I don't think it would be a good value for me because of my light use.

That being said, one place I don't want to skimp is the charger. I have it narrowed down to two Iota DLS-15 and Xantrex truecharge 2 20. I have heard great things about both but they seem to be very different animals. The Iota and IQ-4 seem to be a plug in go... no choices or adjustments except voltage. The truecharge seems quite a bit different with choices for type of battery, equalization routine, temperature monitor for the battery etc... I'd like to hear from people who either have these or understand the differences and could explain them so I can pick the best choice for me.

Also I have read the installs of the link 10 and link lite and those devices are pretty cool. I was wondering what you guys thought of this Doc Wattson meter as an economical substitution. I have enclosed a link to the product and specs.

http://www.powerwerx.com/tools-meter...dc-inline.html

Thanks!

[ShrimpBurrito]

Originally Posted by greentrail

Also I have read the installs of the link 10 and link lite and those devices are pretty cool. I was wondering what you guys thought of this Doc Wattson meter as an economical substitution. I have enclosed a link to the product and specs.

That is a neat little device -- definitely a less expensive alternative to the Link 10/Lite products, as long as you know its limitations. Probably the most significant disadvantage of it is that, unlike the Link products, it does not use a shunt to measure current. A shunt is basically a very small-value resistor that enables the Link product to measure current draw based on the voltage drop across it. Since the Link product is only measuring voltage off the shunt to make that measurement, it can be mounted anywhere in the TM and installed by running small wire to to the shunt.

Since the Doc Watson meter doesn't use a shunt, that means that you hav to install the unit in line with the main wire coming from the battery. Right now, that puts the unit either under the battery cover on a 2720, or somewhere else unaccessible between the battery and the converter, which is where the battery wires go. So you would probably want to cut into that wire somewhere and run it to the unit where it is mounted in a more accessible location.

If you choose the latter approach, be sure to use heavy wire to minimize power loss.

I think there are other convenience factors that make the Link products have more utility. For example, the Ah meter meter resets automatically when the battery is recharged. The Doc Watson resets only after power to it is interrupted. You could simply put a switch in there, but now you're adding cost and hassle.

Dave

Thanks for the quick reply Dave, Thanks for explaining the details of the shunt, I was reading the wiring diagram and wondered what the purpose of that was. I might give that doc wattson a try. I figure I can periodically walk outside and check the meter once in a while to make sure I don't go past 50% discharge.

Can you tell me what charger you use to recharge your T-105's?

[ShrimpBurrito]

I used to use a 6-amp Guest 3-stage charger, which worked great. We go camping about once/month year round, so I would just hook the charger up about 2 days before our departure to fully charge the batteries. Otherwise, the batteries would just sit in the TM, unconnected to any charger.

Gradually, my batteries wouldn't take a full charge (only to maybe 70-80% or so), so I thought they might be sulfated. So I sought out a multi-stage charger that had a desulfate cycle built in, so I bought the Xtreme Charge X100 for ~$100, shown here:
http://www.xtremecharge.com/stage_battery

I now keep the Xtreme charger on the TM 24/7. So far, so good, but I've only been using it about 6 months. It did restore my batteries to the point where they would take a full charge, so I consider that an improvement.

Dave

I just use the three stage charger that is built into the TM.

After 3 years, my pair of group 24 Interstate RV/Marine batteries just did not seem to hold up as well as they used to.

So I bought an external charger for 90 bucks that has both a desulfate and an equalize mode. I ran a few cycles of that and all is well.

So my current strategy is to run the external charger to run a desulfate and equalize charge about once a year, and use the built in TM charger the rest of the time.

You can buy a different converter for the TM, so that it would have a built in equalize and desulfate mode, but that is a lot more than 90 bucks.

I also have changed my recharge strategy. I used to run the generator every other day. Now I run it daily, for half as long.

One of these days I will buy and install a Link10 or equivalent. As it is now I just kinda gues at how long to run the generator. I only use a volt meter to help me guess. I run the generator about an hour per day, during breakfast. I understand that it is best to not let a battery sit too long in a discharged state.

I have had my LinkLite installed for only about a week and just a few hours ago came back from first camping trip having it along for ride. The place we camped was only an hour drive away and we only stayed for two nights. However, having the LinkLite along showed me just how little I will be using a generator in the future. We used only about 29 of 116 usable AH for the trip. Having the AH meter installed in the main cabin is nice. You get constant feedback on things. It is a new toy so I was looking at it a lot. I am really sold on it. I am already noticing that I am getting used to seeing -0.2A on the display when we are just hanging out during the day. Anything other than that and I know someone has a light or a fan on or something and I am already in the habit of following behind folks to turn off the fantastic fan or whatever else they left on unnecessarily. I love the data so much, I almost wish I had some form of cap probe type sensors for the holding tanks.

As for charging, so far I am just living with the stock WFCO 8955 converter to do its 3-stage thing. Perhaps I should put an external charger on the list based upon what others are saying.

Besides using my external when I want to run a desulfate or equalize charge on the TM batteries, I also use in on the two motorcycles and two ATVs.

I bought the Black and Decker VEC1093DBD like this one:

http://www.amazon.com/Black-Decker-V...1674814&sr=8-1

Thanks for the replies and comments guys. Maybe I'm just sweating this charger thing too much. As I research I keep ending up at these marine sites where these guys are living on their boats for extended periods and they really need to depend on their battery bank. For me, it's not really that big a deal. Dave, another follow up how did you know the battery would only recharge to 70-80%? Did the voltage never come up to 12.7 ? or was there another way you could tell.

Thanks

[ShrimpBurrito]

Originally Posted by greentrail

Dave, another follow up how did you know the battery would only recharge to 70-80%? Did the voltage never come up to 12.7 ? or was there another way you could tell.

I measured both the voltage and the specific gravity of the electrolyte (using a hydrometer). The latter is more accurate in determining state of charge, and also allows you to determine whether individual cells in the battery are producing adequate voltage (the lack of which could mean a bad cell, or perhaps an unequalized cell, something I'm not very familiar with).

You don't list what model/year your TM is. If you have a newer TM, then your converter has a 3-stage charger -- however, I don't know exactly what year the factory started installing those. The converter in older TM's don't have such a charger, and will wreck your batteries if you leave it plugged in long term (like for a month+) since they are not intended for long term battery maintenance. That is the reason why I use an auxiliary charger, which I mounted inside the rear compartment.

The model of the converter should be listed on the converter itself, as well as in the appliance chart in your blue book.

Dave

Thanks Dave,
It's a 2006 2720 and if I remember right it's got the newer WFCO charger / converter. I just wasn't convinced that it was a high quality three stage charger.