BAC Forum

General Boards => Technical Support => Topic started by: Bill Borden on December 27, 2011, 08:36:46 PM

Title: battery disconnect
Post by: Bill Borden on December 27, 2011, 08:36:46 PM
Hi Gerald,

Being a new Beaver owner and new BAC member I have a question that I have not found yet in the forum.

We have 2000 Patriot Thunder, my question is, is there a chassis battery disconnect?  Electrical or mechanical, I know about the house disconnect at the door light panel.

We put the coach in storage, they park it inside, left it for 3 weeks, went to pick it up and the chassie batteries were dead.  We have not had a problem with batteries parking at home or elsewhere.  Batteries are less than a year old.

Thanks for your help,
Bill Borden
Cool, California
Title: Re: battery disconnect
Post by: JimDyer on December 27, 2011, 09:29:26 PM
Hi Bill,

I'd be very surprised if there aren't two battery disconnects (fused) back in the battery compartment. They normally have a large chromed handle that rotates 90 or 180 degrees to switch. Then there will be one or two solenoids (fancy word for a heavy-duty relay) which do the actual switching whenyou actuate the switch by the stairs.
Title: Re: battery disconnect
Post by: Keith Oliver on December 27, 2011, 09:40:13 PM
search back for my similar complaint, "what is using all my electricity?".
there was no disconnect, for the chassis batteries, in my 98 Contessa, until I put one in.  The ECM uses enough power, just to keep itself warm and remembering its settings, to drain the pair of chassis batteries in a couple of weeks.
Title: Re: battery disconnect
Post by: Joel Ashley on December 27, 2011, 09:49:12 PM
Bill-

As Jim described, you should find master disconnects relatively prominent in your battery bay, though they come in various configurations and may look different.  Your question to Gerald is appropriate as he is probably as familiar with your year and model coach as anyone here besides actual owners.

In the interim before he answers, I'd add that the switch by the entry door was primarily designed for dealers to use as a convenience between customer tours and coach starts, and as such has a limited effect on battery preservation.  Other parasitic drains on the batteries, not controlled by the door switch, still can run them down over time.  Our coach, stored outside, gets quite adequate battery maintenance from the roof solar panel, but I still keep the master switches off most of the time.

Joel  
Title: Re: battery disconnect
Post by: Dennis Crawford on December 27, 2011, 09:51:35 PM
I have a 2005 Monterey and my chassis batteries will drain down in about a week.  With two fully charged batteries, my Fluke clamp on amp meter shows a 1.2 amp constant draw.  That will take those batteries down in a week.

Dennis
Title: Re: battery disconnect
Post by: Gerald Farris on December 28, 2011, 03:33:10 AM
Bill,
I am not certain if your coach has battery disconnect switches are not. If it is equipped with disconnect switches, they are located in the battery bay, usually above the batteries.

On a lot of coaches, the battery disconnect switches do not cut off the power to the ECM (engine control module). The parasitic drain of the ECM is the thing that kills the chassis batteries if the coach is stored indoors without being plugged into shore power. So even if you have battery disconnect switches, you need to be sure that the ECM is disconnected when you are storing the coach inside without plugging it in or you will still have dead chassis batteries.

If you do not have battery disconnect switches, you can add them, or just remove the cable from the ground terminals for both battery banks when storing inside.

Gerald  
Title: Re: battery disconnect
Post by: Bill Borden on December 28, 2011, 03:38:15 AM
Thank you forall of your input.  I have not seen any reference to a battery disconnect in any of the manuals.  

But if there is battery disconnect there shouldn't be drain, I will put a meter on the battery banks tomorrow, but a in line light tester should light up if there is any power drain.

I will post the results tomorrow.

Bill Borden
Cool, CA
2000 Patriot Thunder 40' C12
Title: Re: battery disconnect
Post by: Dick Simonis on December 28, 2011, 02:48:15 PM
Bill, our 2000 PT does not have a battery disconnect for the chassis (that I've ever found) and the batteries will last ~2-3 weeks.  Found this out the hard way when the echo charger died.  However, with a funcitoning echo charger and a bit of daylight, the solar panel keeps them topped off.

Dick
Title: Re: battery disconnect
Post by: Keith Oliver on December 28, 2011, 05:16:38 PM
The solar panel for the chassis batteries (on my 98 Contessa) is 14" square.  In March, parked outside, near Vancouver BC, there wasn't enough sun/charging area, to keep from a total battery discharge in about 2 weeks.  the bigger solar panels, 2 @ 24" x 48", are not connected to the chassis batteries, only the house batteries, which did survive the two week layup.
Title: Re: battery disconnect
Post by: Dick Simonis on December 29, 2011, 01:26:09 AM
On the 2000 PT, there is one 100W solar panel connected to the house batteries.  The chassis battery is charged via the echo charger.
Title: Re: battery disconnect
Post by: Bill Borden on December 29, 2011, 06:58:45 PM
Thanks for all the input, it is clear that I have to either install a hard disconnect for both battery banks or plug the coach in.

My problem started when we choose to store the coach in doors, so no sun.  After 3 weeks the chassis batteries were dead, the ECM turns out to be the drain.

So I am off to pick up 2 knife style disconnects or I am thinking about installing 2 battery disconnect latching relay's.  The first way is fast, easy and cheap.

The relay would be a project to install, but would in the long run easy to operate, one switch on the dash.

Which would be better?  Comments.

Thanks,
Title: Re: battery disconnect
Post by: Dick Simonis on December 30, 2011, 12:06:18 AM
If I were doing it, my preference would be for a mechanical disconnect.  Not only easy, but reliable and also easy for emergency responders to find and disconnect the batteries if it became necessary.  Also, I wouldn't use a knife switch but a regular battery isolator switch like is used on boat battery banks.

Just my thinking.

Dick