[Gerard]

Gerard,

Try not to over think the coach and its systems. In your mind separate them and your electrical background will have you seeing how it all relates.

The coach has its own DC electrical system, and because it is primarily a 24 volt chassis most of the system is 24 volts. But some 12 volt power is required so that comes from chassis batteries that are connected in series and parallel so Prevost is able to use each voltage as needed. A Vanner battery equalizer keeps the 4 (group 31) or 2 (8D) batteries properly charged.

The house portion of the coach is the same generally speaking, and it has its own set of batteries which may be providing either all 12 volts or in the case of most coaches now 12 and 24 in a fashion similar to what Prevost does with the chassis batteries.

But the house has different needs than the chassis so it is equipped with inverters which are nothing more than battery chargers when shore power or generator power is available, or inverters which take the battery voltage from 12 or 24 volts DC and change it to 120 volts AC.

The house DC systems, such as lights or fans for the heaters, or some valves are powered by the house batteries, while the house AC systems such as appliances or air conditioners are powered by shore power, generator power or through the inverters. None of the various system are co-mingled with the exception they likely have DC voltage to charge both the house and the chassis coming from engine driven alternator(s).

I have oversimplified the descriptions, but the bottom line is don’t think of the coach electrical systems as a single system, but as several isolated systems that go down the highway all at the same time.

[Mike]

Once again I offer my gratitude to you Jon. I will look at the electrical system in a new light.

[Andy]

Red=24 volt yellow = 12 volt all wires from prevost are tatooed with a number=chart tells what they are for. Also all conectors have a tag/code = what they do or which switch circuit they are responsible for.. . some older coaches had blue=120 volt AC in harness( very few wires in system)..Black wires are ground in dc system. Hope this helps. Download key at prevostcar.com Need last letter in your serial ## plus last 4 numbers. Example W-6553 !998 XLE unit number 6553. Bob

[Glenn]

Gerard,

Looking forward to reading your post after OKC, “Everything you need to know about buying, running and maintaining a bus”. Looks like it will be a rather long one!

Seriously, I know where you are coming from when you say there is such a lot to take in, I am in the same boat. Having said that, after only a couple of months, it is starting to make sense. Mainly due to the great people on PC.

[Archived]

Everybody needs to keep in mind that as apparently complex as our coaches are, they are not much more than some fairly basic systems (pneumatic, plumbing, electrical, environmental) all packaged in the same location. The newer coaches use multiplexing for the electrical system which seems intimidating but even that system is no more or less complex than a system with a bunch of relays and circuit breakers.

If you have worked on repairs around the house or on your cars the coach is not going to be much different as long as you take the time to understand the logic behind the system. What is important is to keep things separated in your mind, and that includes developing an understanding that what may apply to a Vantare electrical system might not apply to a Marathon. The coaches do have their differences, but those differences are usually in the details.

[William]

OK,so I just read Jon’s article about undertanding the coachs electrical systems. I thought I would be a challenging read, but was very suprised about how easy it was to understand the concept. Thank you once again Jon and everyone else who had input. It was a huge question I posed earlier and it was handled with the dignity and helpfullness rather than assumed eye rolling because another newbie doesnt understand.

Thank you, thank you, thank you.

[Archived]

While our coach electrical systems are relatively simple to understand given a little time to grasp the concepts of things like inverters, equalizers, and isolators they do have some characteristics that are going to very from coach to coach so while posts about electrical questions may be a great place to start to understand things asked about it is important to keep track of the conversions being discussed.

The Vantare electrical system for example runs all 120 VAC through the inverters, while other conversions such as Liberty (certain vintages) may only run specific circuits through the inverters. What is best for new owners trying to learn the systems is to always try to seek converter specific questions and answers. The same applies to just about any system. With Prevost the systems are consistent as Bob points out in that Prevost has always color coded voltages, and almost always is consistent with circuit numbers. It is always circuit 85 on the Prevost electrical system that is associated with ignition.

While there are a lot of consistencies there are also a lot of variations. Some coach conversions only have 12 volts, some 12 and 24. Some coaches have dedicated generator batteries, some rely on the house batteries for generator start. Some use a single 50DN alternator to charge house and chassis, some use the 50 DN only for the house and a smaller alternator (24V) for the chassis. Some use multiple Bosch alternators, and some have been modified by owners to use other configurations. The reason for being aware of things like this is to understand a correct answer relative to one conversion may not be true for another.

That to me is where it gets confusing and is difficult to keep track of.

[Peter]

Thanks Jon. I have narrowed my serch criteria down (although its just about where it always was). I will be shopping for a Liberty xlii, non-slide, would prefer Girard awnings but will accept Zip Dee. No bunks…I’m single. I believe I have found one that clicks on all cylinders so to speak but am hesitant to mention which one as there are only a select few, and I wouldn’t want someone to get interested in it. I have read all the posts and comments and articles concerning the pre purchase process and will NOT let my peeked interest in what I preceive as the perfect coach get in the way of common sence.

BTY, I dont see a spell checker on the header withing where you type your posts….am I just missing it?

[Archived]

Gerard, If you’re looking for Liberty it will be Zip-Dee and if it’s pre 06 it will be the Zip’dees you will learn to hate.

[John]

There is one for sale at Olympia coach non slide it’s a liberty, if you are interested in a non slide coch

[Corey]

Thanks Corey and Peter

[Archived]

Corey,

Why would Gerard hate the pre ’06 Zip Dee awnings? Just curious.

Mark

[Andy]

Mark, they are the infamous air/electric ones.

[Archived]

We have no spell checker. There was a reason but I can’t remember why. Maybe Tom can jump in.

[Bob]

MM,

Zip Dee has a vintage of awnings that were used by converters from late 90’s to mid 00’s. They looked like the original ZipDee manual awnings because they had the arms and the roll across the top. They were pneumatic / electric and they have proven to be somewhat unreliable unless they are provided with never ending maintenance.

They were succeeded by Girard or ZipDee cantilevered awnings that retracted into a “box” that ran down the length of the coach. Those awnings have been much more reliable although the Zip Dee version had or still has some problems with water getting into the motor.

The automatic Zip Dee awnings with arms have often been a topic of discussion on forums, but it appears that owners who do proper maintenance have not experienced a lot of difficulties with them. Others have thrown in the towel and reverted back to the original manual awnings. To upgrade to the cantilevered armless awnings involves a lot of money to get the needed structural work done for mounting.

No new coaches use the problem version. All are cantilevered awnings.