1985 southwind multi battery set up?

A bi-directional 200-amp battery combiner has a lot going for it mainly the ability to manage automatically, "If one battery charges, they all charge". Takes care of storage issues. The ford-type intermittent duty solenoid likewise is a godsend for cross-jumping to allow a high degree of confidence to get -something- started, the generator and converter or engine and alternator. I will never go back to rectifier based isolators as most have damned poor quality 1/2" press fit rectifiers. I don't like playing games when something does not start. Running switches with thirty feet of wire in my book is a loser. So is running cables hither and yon to connect to a rectifier based isolator. Ever see what a rectifier based isolator does to the -other- bank when the vehicle chassis side rectifier in the isolator fails and keeps insisting that the alternator is actually seeing say 12.1 volts on the voltage regulator sense lead? It isn't pretty. A 17 volt battery acts pretty weird. Get out your "to-order-replacements" clipboard because few goodies in an RV can withstand hyper levels of voltage.

IMHO Rectifier isolators rate right up there with polyglass tires, and shift buttons in the middle of the steering wheel.

edit: inappropriate

We used to own a 1985 Southwind, bought used in about 1990. It was on a P-30 chassis with the 454 GM, and it was set up like your coach. Two roof airs and a 6500 watt Onan genny. I fought battery problems for several months, installed new batteries, built new cables for them, and still chased gremlins. One Saturday afternoon I made a pitcher of Iced tea and spent the rest of the day on a creeper under that beast.
I tracked down every single grounding wire I could find. The primary one for the 12v system was a stud (memory here), that went to the left frame rail. It was a mess. I don't believe the battery cable running to it was ever properly assembled. I built a new one and soldered the copper lugs on it, then cleaned up and prepped the stud and frame.
Fixing it and then chasing down several other grounds and cleaning them up solved all the problems. It took a day...but it was worth it. You might want to check that out.
Also...for smart isolator/combiner units check out www.hellroaring.com (yes, it is legit) they build some very cool stuff. I have one of their units on our Tournament Ski boat and it has been excellent. I've since installed them on several other boats for friends who are also happy.

The majority of older high end RVs that I do still do some work on are connected exactly as your diagram shows. The diode isolators are reliable, simple and extremely easy to diagnose should one fail. The solenoid in your picture is usually connected to a single switch that is often momentary so the hotel and main engine battery can be cross connected to boost either in the case that one got drawn down too far. It is such a great convenience that when one does fail, I get called right away. Many owners have added "combiners" to cross the hotel and main engine battery when there is charging voltage present and this is effective, but when the device fails, I have great difficulty giving an owner instructions to diagnose as it is not a simple test. Most combiners cannot pass starting current and so are of little value if you need to cross the hotel to the main to crank the main engine. This is exactly the same work that I did on other peoples expensive boat before the depression hit here.

Matt

The solenoid is probably only has an intermittent rating,
It is for emg jump start of house batteries to starter battery
The diode isolator is for charging while driving
Some people replace the solenoid with one rated for continuous duty and wire it to the ignition switch or with a toggle, to get a little better charging voltage to the batteries when driving

I would start with a SURE POWER 200-amp battery separator from

allbatterysales.com

BE SURE TO CHOOSE THE "BI DIRECTIONAL" BATTERY SEPARATOR



And follow installation instructions exactly. You will gain battery recharging ability like you won't believe. I like the idea of retaining the Ford starter solenoid as an integral battery booster. But the Bi-directional SURE POWER solenoid allows INTELLIGENT AUTOMATIC charging of ALL batteries, no matter if the house or engine starting battery is being charged. Either one. Yep. When one charges they all charge. Automatic separation. No freakin' switches to forget about. I've installed maybe four or five dozen of them and the RV and yacht owners love the SURE POWER bi-directional battery separator.

Strange, I figured one would kill the other.
So if I took the Iso out (because I will be adding 2 more batterys) would i just the same solenoid or what what you do if you were me?

Thanks agian!

"most last 10-20 yrs, despite what some will tell you."


Should have taken a image of that scrap metal dumpster when I had a chance.

I had to ferret out "ESSEX tower" constant duty solenoids to replace the metal can type. They were rated for 100-amps and usually could be counted on to last two to three times as long as the regular ones.

MAKE SURE your CS-130 alternator in that bounder has a LIVE connection to the "S" terminal in the voltage regulator plug-in. Battery power 100% of the time. Battery power from the HOUSE batteries, NOT the engine starting battery.

Of course this causes CONFLICTS about what the alternator voltage regulator is going to do. The alternator tries to charge more to bring voltage to the HOUSE batteries in line with reality but the rectifiers in the "isolator" don't know that and the engine starting battery voltage soars.

Rectifier based battery isolators have gone the way of the Dodo for a reason. They have mighty serious shortcomings. Good in their day, so were buggy whips.

I like SMART SOLENOIDS especially the 200-amp rated ones, for a good reason.

I can remember when those diode isolators were the greatest thing since the wheel, long before they knew what a fully charged battery was.
I still like the inexpensive const duty solenoids,....most last 10-20 yrs, despite what some will tell you.
And if it ever gives trouble, alls ya need is a jumper across it !

This will certainly work and isn't that unusual. The solenoid is, or can be used for starting or boosting the chassis battery. My '85 Pace was wired like this.

The only drawback with a diode isolator is that you are losing .6v off the alternator to either battery.