Another Battery Question

wealthwise wrote:

westend wrote:
First, 12 V batteries are never wired in series (except in the rare 24 V system). The connection is always in parallel.

If you have connected the batteries in series and they are 12 V batteries, the circuits have been seeing 24 V, this is not a good thing. You would expect that there are fuses and/or circuit breakers faulted. Damage to other devices may occur.

I'm a big advocate for DIY but I think your basic lack of knowledge is starting to hurt you in this case. I would suggest you hire someone to look over your 12 V system. That someone would not be the guy at Autozone. I'd suggest an RV service garage and please, disclose to the folks there what you've done to make everything work, even what didn't work.

Ok well it was wired in parallel, yesterday was the first time I hooked it up in series, but only for a few mins and then I took the cable off all together, seeing how the service fees and rates are around here, I think I'm going to just wait till we get on the road and look for an RV shop somewhere on the road, we don't have any underlying issues other than the 12 volt relay possibly being faulty, I'm not going to waste time with Autozone they don't have enough experience with RVs.
Thanks

I have done some of what you advise, I will printout your advice and use the list as a checklist and I would never check the alternator myself.
Thanks

westend wrote:
First, 12 V batteries are never wired in series (except in the rare 24 V system). The connection is always in parallel.

If you have connected the batteries in series and they are 12 V batteries, the circuits have been seeing 24 V, this is not a good thing. You would expect that there are fuses and/or circuit breakers faulted. Damage to other devices may occur.

I'm a big advocate for DIY but I think your basic lack of knowledge is starting to hurt you in this case. I would suggest you hire someone to look over your 12 V system. That someone would not be the guy at Autozone. I'd suggest an RV service garage and please, disclose to the folks there what you've done to make everything work, even what didn't work.

Ok well it was wired in parallel, yesterday was the first time I hooked it up in series, but only for a few mins and then I took the cable off all together, seeing how the service fees and rates are around here, I think I'm going to just wait till we get on the road and look for an RV shop somewhere on the road, we don't have any underlying issues other than the 12 volt relay possibly being faulty, I'm not going to waste time with Autozone they don't have enough experience with RVs.
Thanks

This reminds me of being at sea around the scuttlebutt and listening to the sea lawyers preach and wave their arms. There are far too many ways to connect things especially in a pusher diesel to make all-encompassing statements about how "this-is-connected-to-that".

OP you need help. Standing right by your side as you do this stuff. Even with 50 years of experience I need to stand back and take a good look before plunging into diagnostics on a pusher. It would help you and anyone working on your rig if you had a wiring diagram from the manufacturer. Not the coach part, the chassis part. Secondly you need to know and understand how to tell the difference between an engine starting battery and a house battery. They have different labels and terminals.

Some stuff is hazardous to so and you need to be damned careful doing it. Like measuring the alternator voltage at the alternator with the engine running. Nasty stuff like spinning fans, pulleys, and belts can endanger you and your meter.

You need to make a list. Without a list you are sunk...

How many volts does the single battery have at rest?
How many volts do the twin batteries have at rest?

How many volts does the single battery have when the engine is started and has been running for ten minutes?

"......................"twin batteries".....................................
............................?

On both sets of batteries, is the voltage on your meter climbing, or is it stagnant? This is important.

Note the SHAPE of the terminal posts on the two batteries and the shape of the terminal posts on the single battery. THIS IS IMPORTANT. WRITE IT DOWN.

Stop the engine

Plug in the coach to shore power.

Do the same voltage check on both sets of batteries with the converter running on shore power. What do you see on the single battery. The twin batteries. Is the voltage rising now or is it steady? How much voltage on both sets of batteries?

A voltmeter digital multimeter, WITH THE TEST LEADS PLUGGED INTO THE CORRECT HOLES ON THE METER, and meter set to VOLTS DC, is fine to connect to a battery. The red lead to the positive side the black lead to the negative side.

Auto parts personnel make six dollars an hour and are one step up from a hamburger flipper as far as expertise is concerned. Forget what he said and do what I said. Just don't screw up and plug the red test lead into AMPS. This is a NO NO. Red lead to VOLTS black lead to NEGATIVE. Look for the DECIMAL POINT on the digital display. This is crucial. Take your time.

To repeat, without writing this stuff down on a list you might as well forget checking anything. Troubleshooting is an inverse pyramid of problem solving diagnosis and is a process of elimination. A regimented process of elimination.

Armed with a clearly readable list of facts and figures return to the forum and report what you have found. This will hurdle round one and really start narrowing the problem down.

First, 12 V batteries are never wired in series (except in the rare 24 V system). The connection is always in parallel.

If you have connected the batteries in series and they are 12 V batteries, the circuits have been seeing 24 V, this is not a good thing. You would expect that there are fuses and/or circuit breakers faulted. Damage to other devices may occur.

I'm a big advocate for DIY but I think your basic lack of knowledge is starting to hurt you in this case. I would suggest you hire someone to look over your 12 V system. That someone would not be the guy at Autozone. I'd suggest an RV service garage and please, disclose to the folks there what you've done to make everything work, even what didn't work.

You need to find a battery shop or a RV shop or mobile RV repair to diagnose. Stay away from at least that Autozone.

Went to Autozone yesterday and talked to one of the big guys and he said that first of all never connect + to - you will blow your system, second that I need to find out if those batteries are connected to the engine I.E. alternator or they will have to put on a charger, I asked him if the 110 hookup charges them and he said no, he also said that if the one battery is at 14 volts it could be a dead cell? He said I could bring the motorhome by and they would check to see if the series batteries are connect to the alternator, I figure the only way to do that is trace the cables back and see if they reach the alternator, my back is acting up so I probably won't be able to do that myself, any thoughts?
Thanks

Connected neg to pos same deal. Checked cable for continuity no problem going to Autozone to see what they say
Thanks for the advice

Wait if the battery is in series then according to this site http://www.zbattery.com/Connecting-Batteries-in-Series-or-Parallel the connection should + to - not positive to positive as I mentioned, no wonder it's not increasing, obviously something was connected wrong, I just hope there is no damage to the cable, what damage could that connection cause?

wealthwise wrote:

westend wrote:
Measure the battery at rest, then measure across the posts with the alternator running. A fully charged battery without a surface charge should measure 12.6V. Measuring across the battery posts with engine running should measure 13.5-14.5 V.

If you have two batteries connected in parallel and only one is charging, you have a wiring problem or a bad battery.

Ok well I did measure before and after and it didn't change so being that it's a new battery I'm going with a wiring problem, more than like the culprit has to be the cable that connects the two batteries from negative posts, so I guess If I take the cable off and test for continuity I should be able to know if the cable is bad. unless there is another method I don't know about. Will it do any good to put the battery on a charger? I'm guessing not really since I need to find out what with the wiring, forgive me if I sound redundant but I'm beat and shouldn't even be replying to this, lol

Understood.
Yes, you can check the cable for continuity. As long as you have the batteries separate, try to charge the one you think is bad, doing the same start and finish measurement recommendations.

westend wrote:
Measure the battery at rest, then measure across the posts with the alternator running. A fully charged battery without a surface charge should measure 12.6V. Measuring across the battery posts with engine running should measure 13.5-14.5 V.

If you have two batteries connected in parallel and only one is charging, you have a wiring problem or a bad battery.

Ok well I did measure before and after and it didn't change so being that it's a new battery I'm going with a wiring problem, more than like the culprit has to be the cable that connects the two batteries from negative posts, so I guess If I take the cable off and test for continuity I should be able to know if the cable is bad. unless there is another method I don't know about. Will it do any good to put the battery on a charger? I'm guessing not really since I need to find out what with the wiring, forgive me if I sound redundant but I'm beat and shouldn't even be replying to this, lol