Converter not charging batteries

[facalton]

The converter is not fully charging the twin batteries. It will charge them to about 75%. I put an external charger on them and they reached 100% Does this mean I need a new converter or is there a way I can correct the problem?

TIA

[Veebyes]

Start with the basics & check all connections between converter & battery bank.

If you determine that the converter is at fault you might consider upgrading to a multi stage programable charger & get all of your 12V needs from the battery bank, just like boats are set up.

While you are in there get a pure sinewave inverter. Do not get a inverter charger. If one part goes bad the whole thing needs to be replaced. Separate units means just the faulty unit gets replaced.

[wa8yxm]

facalton wrote:
Converter: Parallax Power Supply. Electronic 7100 Series.

Parallex 7100 has two versions 71xx and 71xxt The T is two stage and might get you to "Full" Either live with it (Finishing with an external Smart Charger) or upgrade the "Guts" of the unit with a Progressive Dynamics 4600 series (Match the last 2 digits as close as possible)

The 7100 is a single stage (Float) Charger. it does not do bulk or ansorption the 4600 does. The 7100 T has a "Timed" Bulk phase when you first plug it in.. I'm guessing if you unplug wait a few minutes and re-plug that "Boost" mode will finish the charge (may take a couple replugs)

Also how accurate is your method of measuring charge?
A temperature compensated hydrometer is accurate.
Other methods (Unless lab calibrated) not so much.

[facalton]

Replaced the power supply on the parallax 7100. All issues resolved and working properly. Over time the battery charging system gets weak and needs replacing.

[pianotuna]

facalton wrote:
Converter: Parallax Power Supply. Electronic 7100 Series.

I would replace it and move to an inverter charger. I left my converter in place but unplugged.

[Lwiddis]

If you buy a new converter get a model with a setting that will charge Lithium batteries but needing to plug in to charge your batteries gets old very quickly. Solar is my first recharging method. A Noco Genius AC to DC plugs into the truck when driving and is my second recharging method. The third method, Noco plugged into a generator, is no longer. I don’t take the generator. I’ve disabled my seven pin and converter charging methods.

[facalton]

Converter: Parallax Power Supply. Electronic 7100 Series.

[enblethen]

While locating information, use a voltmeter to test voltage.
Check voltage at the converter and then at the battery. If connections are bad somewhere in the circuit voltage at the battery will be substantially lower.

[theoldwizard1]

time2roll wrote:

Or if it says WFCO just plan on replacing it.

WFCO is what comes with most RVs. Concur, replace it with one that does multi-stage charging.

If you are thinking about getting an inverter, now is the time to get a combination inverter/charger/automatic transfer switch.

[pianotuna]

How are you determining 100% state of charge?

Make and model of the converter would be needful to give more than a general answer.

[time2roll]

Post the model number of the converter.
Or if it says WFCO just plan on replacing it.

[JBarca]

Hi,

What brand/make and model and size is the power converter? And how old is it?

Do you have a voltmeter? When the converter appears to get to 75%, what was the charging voltage before the 75% and then after the 75%? Do the test at the battery terminals and ideally reported in at least one decimal point, 2 decimal points is better.

Also, how long was the system sitting at 75% and not going any higher? A few hours or a day or more not gaining any higher state of charge.

What are you using to measure state of charge?

We are making the assumption your system worked before and now does not. Is that the case, or did you just buy the camper and this is what you have?

By chance, was there any power draw going on inside the camper when the system stopped charging any higher? If yes, what was powered up?

What group size twin battery's are they? Group, 24, 27 31 etc. And are they lead acid or other technology.

We need some more background to help back into what might be the issue to give better answers.

Hope this helps

John

[enblethen]

I would check connections between converter and battery.
What kind of rig, make and model?