converter that charges ship batteries

[pbarge]

Hello!


First time poster. It appears that I need to replace my 2006 Georgetown 359TS ship's batteries. My question is that when connected to shore power, what voltage should I see with a multi tester to determine if the converter is properly charging the ships batteries?


Thanks in advance!


Pat

[TitanMike]

Originally Posted by pbarge

Hello!


First time poster. It appears that I need to replace my 2006 Georgetown 359TS ship's batteries. My question is that when connected to shore power, what voltage should I see with a multi tester to determine if the converter is properly charging the ships batteries?


Thanks in advance!


Pat

With batteries disconnected from converter you should read over 13 volts Ideally 13.25+). Battery disconnect switch should handle this but if you still read voltage at coverter output terminals with shore power disconnected, just remove the ground cable from your battery bank (the one that goes to the frame).

If you leave the batteries connected and they're drawing current from the converter the voltage reading can be low and falsely condemn the converter.

If you do have the 13+ voltage reading at the converter then reconnect batteries and check voltage reading at batteries. It will be lower but should be more than 12.8 volts.

Other things to check are the batteries themselves. If Lead Acid batteries checking Specific Gravity of cells is a good first step. If electrolyte levels are low, add distilled water and let charge for a day before checking specific gravity. Cells should read close to even with a max difference between cells of "50 points" (.050 on the hydrometer scale).

Also, if converter voltage at output terminals is Low or Non-existant, check the reverse polarity fuses in the power center or on converter. These are 2-3 fuses separate from the other fuses that feed the lights, pump, etc. Can also be on the actual converter itself, depending on type. If any of them are blown, the converter can't charge batteries.

[pbarge]

Thanks for the ideas! I feel that the batteries need to be replaced. They certainly look old and electrolytes are low with a lot of corrosion. These are Interstate HD24-DP's that don't seem to have a good reputation in the RV world and were with the coach when I bought it in Oct. 2018. When connected to shore power, I tested both batteries terminals and only saw about 3 volts or less. So I was wondering if the converter was working. I've checked the fuses that are under the entry steps and under the bed in the back bedroom. I also checked the two 40 amp fuses that were on the converter itself. I opened the battery disconnect and tested the all of the red hot wires from the coach and had no voltage at all. So it appears that the converter is not working, but does feel warm to the touch. Any ideas where any other fusses might be located on a 2006 Georgetown 359TS?


Pat

[TitanMike]

Originally Posted by pbarge

Thanks for the ideas! I feel that the batteries need to be replaced. They certainly look old and electrolytes are low with a lot of corrosion. These are Interstate HD24-DP's that don't seem to have a good reputation in the RV world and were with the coach when I bought it in Oct. 2018. When connected to shore power, I tested both batteries terminals and only saw about 3 volts or less. So I was wondering if the converter was working. I've checked the fuses that are under the entry steps and under the bed in the back bedroom. I also checked the two 40 amp fuses that were on the converter itself. I opened the battery disconnect and tested the all of the red hot wires from the coach and had no voltage at all. So it appears that the converter is not working, but does feel warm to the touch. Any ideas where any other fusses might be located on a 2006 Georgetown 359TS?


Pat

If you have 120 Volt power going into the Converter and no power out, with the two 40 amp fuses checking good, it's highly likely your converter is bad. That said, do the 12 volt accessories (lights, water pump, furnace fan, etc) work when plugged into shore power and battery disconnected? If so, Converter is good. If not, Converter bad.

As for the converter being warm, that could be normal if the transformer section is OK but power rectifier/regulator is bad.

Based on the description I'd say your batteries are bad. For replacements the Group 24 are a little small. If using 12 Volt batteries I'd use Group 27, Group 29, or Group 31 as they all have much more capacity. Even a pair of 6 V Golf Cart batteries in series would be better. All depending on room of course.

[pbarge]

I tested the lights and fans with the batteries disconnected. They all work! Must be the batteries. One more question tho....this all started because I could not get the front slideout to come in. The two rear slideouts work. Have any ideas on this? Do you know where the access to the front slideoeut motor and electrics are?

[TitanMike]

Originally Posted by pbarge

I tested the lights and fans with the batteries disconnected. They all work! Must be the batteries. One more question tho....this all started because I could not get the front slideout to come in. The two rear slideouts work. Have any ideas on this? Do you know where the access to the front slideoeut motor and electrics are?

My first thought would be to check for inline fuse to slide motor. Every application is a little different but all are usually in wire connecting to battery disconnect.

[pbarge]

Thanks!

[camaraderie]

Those interstates if in good condition are El Cheapo small dual purpose (DP) batteries. This is fine for folks who plug into a park receptacle all the time...but if you are gonna booddonck...recommend you get DEEP CYCLE replacements in the largest size that will fit your tray....usually that is a pair of Group 27's ...but even better would be group 31's or switching to a pair of golf cart GC2's .
In 2006 you may have had a constant voltage single stage charger/converter which would normally charge at 13.6V continuously and current would taper down as battery gets closer to 100%. This is NOT a good charger to leave plugged in full time and it takes longer to charge than the same amp modern 3 or 4 stage charger.
If you have a more modern charger and a fairly deeply (50% or less) discharged bank...you should see initial voltage in the 14.4V range... which will then drop to the mid to upper 13.8V range for absorbtion and finally drop to 13.2V or so as a maintainer voltage (float cycle) which may be left plugged in. This is all measured at the battery terminals while plugged in. To measure ACTUAL state of charge on batteries AFTER charging overnite...disconnect the negative wire for 24 hours. 12.7 volts measured at the terminals would mean a 100% battery...anything 12.4 or under would mean significant loss of capacity. Anything 12.2V or lower means go find some new ones before you go camping!
Quicker way than waiting 24 hours is Mikes turkey baster method described above.
Good luck with it all.

[pbarge]

Thanks for the great ideas! This forum is such a great resource! I replaced the batteries, and was able to retract the main slide. This is a head scratch-er since the rear slides would work and with the batteries removed, while plugged into shore power, allo of the lights and furnace blower worked! Does it seem to this community that there is something amiss with the converter charging the batteries?

[camaraderie]

Unlikely...but if you'll put a simple voltmeter on the battery terminals while plugged in...you can tell in 5 seconds.
Lots of instructional videos on you tube if you don't know how. They use cars...but it is all the same and plugging in the RV is the same as starting the car engine. If you're gonna own an RV you need to own a multimeter!
Here's a link. https://www.autozone.com/diy/battery...h-a-multimeter

[Danesville]

Do you have a switch by your stairs that say “store” below it?

[pbarge]

I do.

[Danesville]

so that switch controls what I call the latching relay, push the switch towards store and you have no charging from converter going to the batteries. If you push the switch up to "use" mode you will hear the relay click and you should show about 13.25 volts at the batteries and now will be charging

[pbarge]

On the battery disconnect panek, there is a red light on. It stays on regardless of which way I move the toggle switch to "Use or Store". Is this normal or is this an issure?

[Danesville]

Yes the red lights stays on either way

[pbarge]

So then, the only way to know if its charging is with a voltmeter? What voltage should I see?

[TitanMike]

Originally Posted by pbarge

So then, the only way to know if its charging is with a voltmeter? What voltage should I see?

Over 13 volts

[camaraderie]

If you boondock instead of plugging in...you should strongly consider getting a true battery monitor like the Victron and you won't need to check with a voltmeter, A monitor will tell you.
What % charge or amphours are left in your batts.
When you hit 50% and NEED to recharge.
When you hit 100% and can turn off the generator or unplug.
How many amps your coffee pot takes each morning.
The net sum of your solar panel amps being delivered while the coach is in use.
How much of a parasitic draw you have...and when you've found the source(s) etc.
It will pay the $150 bucks it costs back in both time and money saved.
If you don't boondock...you don't need all this info. Just get a voltmeter panel on Amazon for 15 bucks and you'll know when you're charging...bulk 14.4V, Absorbtion 13.8V and float 13.2 V...or close to those values if NOTHING else is running.

[pbarge]

Hey thanks for the ideas! I'll check out the voltage monitor...we don't usually boondock, but it is a possibility in the future....I'll check the charging status tomorrow while plugged in shore power....

[Danesville]

Also depending on which converter you own you may be able to connect a charge wizard(just plugs into the converter)and really helps to maintain the batteries without boiling them dry or over charging. i got my wizard off of amazon works excellent