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Author Topic: Electrical gurus  (Read 1381 times)
wal1809
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« on: September 28, 2010, 07:14:18 AM »

Went out to the bus this morning and she was dead.  Accesories were working but not even a click when I hit thr starter.  Long Stiry short a volt ohm meter showed 7 volts in the one battery I checked.  I have a charger on it now and will see if that gets it started.  It has done this before when sitting for a long time. 

My first question is do you fellas kill the battery switches when you park for a long time?  My guess is I have a very small short somewhere in the electical.

My second question is how do you go about tracking a short like that?  Is it a matter of turning the ignition off and testing every wire I find with a volt ohm meter?
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« Reply #1 on: September 28, 2010, 07:21:02 AM »

I think you will find that most of us always turn the coaches off at the master disconnect.  I figure, after years of abuse and use, these things may have dozens of shorts in systems that were disconnected, bypassed or hacked up.  I'd think it would be a monumental effort to find all of the issues, especially if the coach was already converted.  I know a good number of members here have completely rewired their coaches.   They are probably in the clear, but relays and other pieces may still drain the batteries over a long period of non use.  Just my 2 cents..

Good luck!
Glenn
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Glenn Williams
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HighTechRedneck
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« Reply #2 on: September 28, 2010, 07:42:19 AM »

... It has done this before when sitting for a long time. 

My first question is do you fellas kill the battery switches when you park for a long time? 


Yes.  I recall when I got my bus and I read the Operating Manual for it, somewhere it even said when parking the bus for longer than a few hours the battery disconnects should be moved to the off position.

Phantom electrical drains are very common.
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« Reply #3 on: September 28, 2010, 08:13:00 AM »

  Finding electrical drains and shorts can be very hard. Finding the actual circuit though isnt to difficult, but can be time consuming. You start with shutting off all loads by turning switches to off, etc.. Disconnect the battery cable and test for voltage between the battery cable and the battery terminal. If there are no drains or loads, there should be ZERO voltage.

  If there is an excessive amount of load, it could blow the fuse in your meter. You can touch the cable to the battery and note the spark before using a meter, if it makes a good snap or spark, you have an excessive load somewhere and you will have to isolate it. You will have to start disabling circuits one by one, either by removing fuses, or disconnecting relays, until you locate the faulty circuit. On a Bus with litterally a 100 circuits or more, it could take a while, but its the only way.

  Once you isolate the circuit, 999 times out of 1000 it is NOT the wiring, but the units on that circuit. If it is actual a short in the wiring, normally that circuit will have tripped the breaker or blown a fuse. Use continuity tests to find shorts in wiring.
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FloridaCliff
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« Reply #4 on: September 28, 2010, 08:42:09 AM »

Wayne,

I used to hit the disconnect everytime, but not anymore.

My problem was, that I have two systems, House and Start batteries.

And as previously said, a small phantom load will drain them dead, given enough time.

Had it happen a few times.

What I did was to change the lead-acid start batteries to AGM, and put them in parallel to my House batteries.

This way they all had the same charge profile.

I then added a 24Vdc 3 stage charger, hard wired in, that only receives power when it is plugged into shore power.

It also has a generator only outlet should I want to power it while boondocking.

Keeps all the batteries fully charged and happy, all the time.

My old main battery disconnect is between the Start and House systems, should I want to keep them separate.

Did this about 15 months ago and no problems so far.....YMMV

Cliff
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wal1809
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« Reply #5 on: September 28, 2010, 08:55:08 AM »

Every reply here seems to be derived from experience and wisdom.  I reckon I need to get familiar with the kill switches until I test the circuits.  I have had a charger on each battery for a little while now and pushed the start button.  She is coming back to life.

What kills me is I  am in full swing trying to finish the conversion to a two tank waste vegatable oil for fuel system.  When I parked the bus last time I backed it too far into the barn to open the engine door.  So I have to wait to fire it up before I can finish the project I set out to do for today.
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robertglines1
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« Reply #6 on: September 28, 2010, 09:01:07 AM »

anything you have hooked into dc system :TV booster-cell booster-clock in bus or anything that has a transformer on it will pull a small amount of current..even something plugged into cigarette lighter like a navigation device or cell phone charger..if you have a ddec it will pull current with ignition off..I just turn master off
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« Reply #7 on: September 28, 2010, 09:06:59 AM »

What kills me is I  am in full swing trying to finish the conversion to a two tank waste vegatable oil for fuel system.  When I parked the bus last time I backed it too far into the barn to open the engine door.  So I have to wait to fire it up before I can finish the project I set out to do for today.

If you don't want to wait, use an air compressor to air it up enough to release the emergency/parking brake.  Then use a tow rope or several passes of other rope attached to the front tow hook and use your truck to pull it forward a touch.  On smooth level ground it should move easily.  Here at the shop they often use a tow link and a pickup to move non running buses around the lot.
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Van
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« Reply #8 on: September 28, 2010, 09:24:38 AM »

Wayne, if your eagle's elec system is pretty much stock, as soon as you turn on the master there are relays activated to send juice to the front panel. I found this out the hard way, Now when not in use I kill the Switch out of Habit. Any thing that is hooked directly to the start Batts and not through the switch will slowly draw down power, even the memory on a car radio in time will drain you down. Good luck. V
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« Reply #9 on: September 28, 2010, 10:11:01 AM »

Wayne, Just turn off the disconnects after each use and you don't have to worry. I still check for voltage before I crank to start, put them on a charger to give them some life if needed, then hit the start button. Has worked every time so far! Wink

Van is correct, relays take juice and they are powered even though the coach is not running.
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« Reply #10 on: September 28, 2010, 11:19:10 AM »

Wayne, the largest draw on your 10 is the voltage regulator and alternator without cutting the master those 2 items remain hot they draw 6 volts from the relay in the rear you can rewire that part to work off the ignition switch if you so desire I had mine wired that way to keep from going to back and raising the rear door. lazy huh
Do you have the standard Eagle disconnect 2 switches 1 for each battery if so disconnect both


good luck
« Last Edit: September 28, 2010, 11:26:18 AM by luvrbus » Logged

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white-eagle
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« Reply #11 on: September 28, 2010, 06:36:38 PM »

clifford, standard on mine is 3 batteries and 1 disconnect?  or is that not standard?

wayne, i turn my batteries off all the time, but they are connected to the inverter/charger when i'm plugged in or genset in use so that they get charged up.  i have a knife switch connection.  i didn't know that they use power on the regulator, i just know i was told always shut the batteries off and they'll never be dead when you try to start. :-)  Per mr. conrad.
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Tom
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luvrbus
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« Reply #12 on: September 28, 2010, 07:00:11 PM »

No Tom your has been redone the model 15 had 3 shut off switches plus a real nice monitoring panel and gauge to check the voltage on each battery.


good luck
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wal1809
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« Reply #13 on: September 28, 2010, 07:35:18 PM »

I feel a bit ignorant right now.  I have been working all day today right where the switches are located, or switch.  I don't know if I have 1, 2 or 3 switches.  Huh!!  Glad I can call myself an idiot sometimes.  I will strt makin it a habit from now on.  I do believe y'all are right.  It might save my hiney one day.
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