Need a quick answer from the battery guru's

KATOOM wrote:
Whats the best and easiest way to get some resistance measurements and monitor charging voltage from the convertor? Thanks.

For testing I would just use a common multimeter set to DC volts. Check the voltage on the main terminals where the converter hits the fuse panel. Often a bigger red and white wire. Then direct on the battery terminal. Check a few times over an hour and post the results. The issue will be immediately obvious.

A weekend's worth of use is a whole different animal than relying on a converter and generator for weeks-on-end.

A manual battery charger is useful to top charge the batteries to inhibit hard sulfation. Charging the batteries at 14.8 volts (flooded lead acid) is about the fastest way to reach full, or near full charge. Others can wait hours on end for a gyro gearloose converter to try its best. But gasoline is going up in smoke along with the contents of my wallet and I am unwilling to pay hundreds of dollars "proving a point ("Well full charge CAN be done with a Markleberger Converter. Just give it a few extra hours. Ignore the generator").

I use a CHEAP 10-amp manual charger and an equally cheap manual timer to get better results than paying hundreds and hundreds of dollars for an "upgraded" converter when relying on a generator. If you already have a three step "trams" converter it is good enough as is. As long as it does not malfunction.

Whats the best and easiest way to get some resistance measurements and monitor charging voltage from the convertor? Thanks.

^^^^ swap it out for a 35 amp. I did and it works fine. I had planned on getting 1000w generator but spent the money on solar.

It's a two-edged sword. I'm one of the fortunate ones that moved the WFCO next to the batteries and now the 8955 rated for 55 amps will actually put out 65 amps to the batteries. Unfortunately, my Yamaha 1000 can no longer power the converter at that high output. Fortunately with the solar I rarely use the converter. :)

KATOOM wrote:
As usual, everyone here is very helpful and a wealth of knowledge. But as I was expecting, everyone quickly went from simple to far beyond my scope of knowledge on the subject. :h It seems that I best be testing my convertor before I change anything. At the moment, my batteries are always up (as far as I know), so I can only guess that my convertor is doing its job while the trailer is plugged in.

In regards to distance between batteries and convertor, thats about 7-8 feet, or the width of the trailer.

Are you sure about the wire distance- RV builders like to use a country mile of light gauge wire on the typical trailer/Moho install. Reason it is this way is they install the wire before building the floor/deck and wall framing pulling through each assembly segment as the trailer is built without any thought except a fast build time.

My experience many times is 20' 8ga wire lengths to span a 7-8' linear distance due to under/up/over/down type routing.

You are correct the best thing to do is some resistance measurements before doing any work to evaluate the wiring in place plus monitor charging voltage as smkettner suggested.

As usual, everyone here is very helpful and a wealth of knowledge. But as I was expecting, everyone quickly went from simple to far beyond my scope of knowledge on the subject. :h It seems that I best be testing my convertor before I change anything. At the moment, my batteries are always up (as far as I know), so I can only guess that my convertor is doing its job while the trailer is plugged in.

In regards to distance between batteries and convertor, thats about 7-8 feet, or the width of the trailer.

Gdetrailer wrote:

Wayne Dohnal wrote:

If you have a RV manufactured within the last 10 yrs you most likely will have a more modern converter which uses a switching power supply. These converters can supply the FULL rated amperage into the battery.

Unless it's a WFCO converter, then odds are it will never go into boost mode.

Actually there has been some folk that simply upgraded the wire size and or shortened the distance between the WFCO converter and battery and were successful at attaining boost mode. But with stock wire and or distance you are most likely correct.

I myself have a PD9160 with charge wizard and have no issues with all three modes.

yes, a few have been successful with the WFCO's, but most have not. Way to many TT manufacturers have a long enough distance between the converter and batteries that getting a WFCO to work is an excercise im futility regardless of what wire you may try, myself included.

BTW, in the last month I've run across 3 campers who were scratching there heads because after running a charger ALL day long, the cheap battery indicator showed 1 light less than full charge. Guess what, ALL 3 had the WFCO, and digging out my handy dandy clamp on ammeter and fluke voltmeter the reason was obvious. Battery voltage 13.4-13.6V (not in bulk mode) and charging current 10A or so. Only marginally better than the typical 6A auto store charger. Trying to get a pair of GC or big 12V charged like that ain't gonna happen anytime soon.

After our first weekend out, I tossed the WFCO and replaced it with a PD drop in and a PD 60A in the pass through. that way if needed I can parallel them and my honda 2000's and stuff 100+A into my bank of 4 GC batteries.

My advice is that unless you like to tinker, toss the WFCO and go with a PD, Iota, or Powermax Boondocker. Or, if your cash strapped, get one of the B&D 40A vectors, I have one to "loan" to those in trouble and equalize/top off my batteries. A very good charger.

KATOOM wrote:
I have a WFO 55 amp Power Convertor and the trailer is a 2005. Does that help? I was told through other threads that most convertors dont go into boost mode and wont charge the batteries more than a trickle when using the generator. Thats when I was also told that forgoing the power convertor and just using a separate battery charger would work better to bring the batteries up to a more reasonable charge in a short amount of time.

Test the WFCO before spending money. When the battery is low you are looking for voltage to steadily rise into the 14.0 to 14.5 volt range over 20 to 60 minutes. Measure both at the battery and at the fuse/converter panel. If voltage sticks closer to 13.4 - 13.6 then you are just slow charging.

If you decide to replace the WFCO I recommend the PowerMax replacement main board assembly. This is the most direct bolt in replacement. 1 battery I suggest the 35 amp, 2/3 batteries 45 amps, and 4+ get the 55 amp.

http://www.bestconverter.com/WFCO-Powermax-Main-Board-Replacement_c_196.html

Progressive Dynamics and IOTA are also excellent.

If you must get a portable I would go with the 40a B&D linked above. Yes you can run this at the same time as the converter. Although I would get the portable started first and plug in the main RV cord second.

Either way it will take 2 to 4 hours to get a low (<50%) battery up to 90%. The last 10% takes an additional 4 to 8 hours so that can wait until you have utility power and lots of time.

KATOOM wrote:
I have a WFO 55 amp Power Convertor and the trailer is a 2005. Does that help? I was told through other threads that most convertors dont go into boost mode and wont charge the batteries more than a trickle when using the generator. Thats when I was also told that forgoing the power convertor and just using a separate battery charger would work better to bring the batteries up to a more reasonable charge in a short amount of time.

Even if your WFCO doesn't go into boost it is still going to do a far better job than a 6 amp charger. Since my WFCO actually works (rare according to this forum) you might try upgrading your converter to battery and convert/battery ground wire to maximum that will fit. Maybe your WFCO will then work, otherwise change out to another converter or get at least a seperate 40 amp charger