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Topic: Low voltage DC at all outlets, and other self inflicted problems (Read 6 times) previous topic - next topic
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Low voltage DC at all outlets, and other self inflicted problems
Yahoo Message Number: 97848
Hi all,

I was having problem using my small 100W Black & Decker inverter in my 82 LD to recharge my laptop (17W consumption).  Although the house battery voltage is 12.5V, the inverter keep shutting down.  So I measured the voltage at the 3 DC outlets, and none of them was above 11V.  I traced the problem to the Battery/Converter switch.  The input voltages (battery or converter) are as expected (12 for the converter, and 12.5 for the battery), but the output is only 11V.
Mystery solved.

Question:  Where can I find a replacement Battery/Converter switch? Do I have to order it from the mothership?
 Self inflited problems:  While probing around the LD electrical panel to diagnose the above problem, I ruined 3 (yes, three) things!  I must have shorted some circuits.  Now my gray and black tank LEDs does not work anymore.  And the battery condition guage is also non responsive.  What can I do?  Help!

Thanks,

Sam
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #1 –
Yahoo Message Number: 97857
"Now my gray and black tank LEDs does not work anymore. And the battery condition gauge is also non responsive. What can I do?"

I suspect that it's going to be tough to get repairs done on a 1982-vintage board like that. I can suggest a couple of alternatives.
They are not cheap, but they'll give you far more useful information than the LED gauges, which are--let's face it--both inaccurate and imprecise.

1. Install Garnet SeeLevel II digital tank gauges:    http://www.andybaird.com/travels/skylarking/improvements/gauges.htm>  
2. Install a Link-10 or XBM digital battery monitor.

Each of these enhancements will cost you about $250 plus labor. As I said, they're not cheap. But the accuracy and useful information you'll get from them are so far superior to the crude LED gauges in any LD--even the latest ones--that in my humble opinion they are well worth the money.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #2 –
Yahoo Message Number: 97863
Quote
1. Install Garnet SeeLevel II digital tank gauges:

2. Install a Link-10 or XBM digital battery monitor.

Each of these enhancements will cost you about $250 plus labor. As I said, they're not cheap. But the accuracy and useful information you'll get from them are so far superior to the crude LED gauges in any LD--even the latest ones--that in my humble opinion they are well worth the money.
Thanks, Andy.  I will look at the link.

Sam
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #3 –
Yahoo Message Number: 97864
"Now my gray and black tank LEDs does not work anymore. And the battery condition guage is also non responsive."

Sam
 You may not have damaged anything. Since all the LED indicators are on one circuit board, you may have accidentally disconnected the board's ground or power wire or maybe blew the panel's fuse.
There really isn't much in one of the indicator boards to go bad; it's just a bunch of resistors and LEDs.

Before investing in a SeeLevel and Link 10 (both great upgrades), I would troubleshoot the panel and find out what happened.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #4 –
Yahoo Message Number: 97866
Quote
You may not have damaged anything. Since all the LED indicators are on one circuit board, you may have accidentally disconnected the board's ground or power wire or maybe blew the panel's fuse.
There really isn't much in one of the indicator boards to go bad; it's just a bunch of resistors and LEDs.

Before investing in a SeeLevel and Link 10 (both great upgrades), I would troubleshoot the panel and find out what happened.

Larry
Sounds very encouraging, Larry.  But my electrical knowledge is limited.  It stops at the basic voltage, amperage, polarity...  Any idea what I should be looking for?

Thanks,

Sam
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #5 –
Yahoo Message Number: 97867
Quote
Sounds very encouraging, Larry.  But my electrical knowledge is limited.  It stops at the basic voltage, amperage, polarity...  Any idea what I should be looking for?
I have also double checked all the fuses behind the Lazy Daze sub panel.  They are all good.
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #6 –
Yahoo Message Number: 97903
Quote
"Now my gray and black tank LEDs does not work anymore. And the battery condition guage is also non responsive."

Sam
 I'm pretty sure the LEDs and battery condition gauge are on the same
fuse in my '01 RK. Check out the fuse descriptions in your LD manual.
Good luck, Dean
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #7 –
Yahoo Message Number: 99651
Quote
Self inflited problems:  While probing around the LD electrical panel to diagnose the above problem, I ruined 3 (yes, three) things!  I must have shorted some circuits.  Now my gray and black tank LEDs does not work anymore.  And the battery condition guage is also non responsive.  What can I do?  Help!
An update:

Since I didn't know where to begin, I decided to ignore those problems.  Who needs the battery gauge, when a voltmeter is available? Same thing with the black/gray tank levels:  When your water level is low, time to empty the tanks.
 Well, this morning, instead of turning on the water pump, I press the tank level switch instead.  Guess what?  The LED lit up!  The battery condition gauge is operational too!  I'm speechless.  I have absolutely no idea what's going on.
 I only thing that have changed since is the replacement of the coach battery.

Sam
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #8 –
Yahoo Message Number: 99652
Quote
Well, this morning, instead of turning on the water pump, I press the tank level switch instead.  Guess what?  The LED lit up!  The battery condition gauge is operational too!  I'm speechless.  I have absolutely no idea what's going on.
Sam, one thing you'll often find in older fuses of the type used in your converter 12V panel is internal mechanical deterioration that will cause a big or intermittent voltage drop. If you haven't already done so, I would replace them all. If you have any plans to replace the converter, newer models will come with a fuse panel that uses more rugged automotive-style fuses.

Steve
2004 FL
2013 Honda Fit
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #9 –
Yahoo Message Number: 99653
Hey Steve...I have the same setup im my 85...Are You saying replace the clear pop-in 30,20 15 amp fuses is a good idea?? I have been meaning to get extras just in case...but didn't know about having "fresh" ones is something to consider. Thanx  John O.
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #10 –
Yahoo Message Number: 99654
Quote
Sam, one thing you'll often find in older fuses of the type used in your converter 12V panel is internal mechanical deterioration that will cause a big or intermittent voltage drop. If you haven't already done so, I would replace them all.
Good idea.  I'll do that.

Quote
If you have any plans to replace the converter, newer models will come with a fuse panel that uses more rugged automotive-style fuses.
My converter is so old, I'm no longer using it.  I have discarded it.
Now when I'm home, I just attach my manual battery charger to the battery.  I'm still weighing the pro and con (function, cost, practicality) of a converter vs an smart battery charger.

Thanks,

Sam
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #11 –
Yahoo Message Number: 99666
Quote
Hey Steve...I have the same setup im my 85...Are You saying replace
the clear pop-in 30,20 15 amp fuses is a good idea?? I have been meaning to get extras just in case...but didn't know about having "fresh" ones is something to consider. Thanx  John O.

 I've seen two types of failure:
 - the fusible element develops a microcrack - a nearly invisible gap that either registers as an 'open' circuit or very high resistance.

- the solder holding the ends of the element develops an oxidized barrier at the attachments.
 Both failures are age-related, and the simplest way to avoid a problem is to replace the fuses en-masse about every decade.

Steve
2004 FL
2013 Honda Fit
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #12 –
Yahoo Message Number: 99668
Quote
My converter is so old, I'm no longer using it.  I have discarded it.
Now when I'm home, I just attach my manual battery charger to the battery.  I'm still weighing the pro and con (function, cost, practicality) of a converter vs an smart battery charger.
I assume you mean you've removed the Power supply section of the converter that both charges the battery and supplies 12V to run appliances and lights? And, that you have left the battery connected directly to the 12V fuse buss for the low-voltage circuits?
 If so, one thing to consider is how the output of your battery charger appears to your 12V circuits. It may have insufficient filtration and voltage regulation to prevent possible annoying artifacts on the 12V line that could potentially damage systems in the m'home. As inadequate the converter may be as a battery charger, as a 12V power supply, it was pretty well filtered, and maintained a safe voltage for all systems.

Steve
2004 FL
2013 Honda Fit
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #13 –
Yahoo Message Number: 99670
Quote
You may not have damaged anything. Since all the LED indicators are on one circuit board, you may have accidentally disconnected the board's ground or power wire or maybe blew the panel's fuse.
There really isn't much in one of the indicator boards to go bad; it's just a bunch of resistors and LEDs.
Actually, ours has a several IC's, presumably comparators and zeners to ramp the output to the appropriate LED.

Steve
2004 FL
2013 Honda Fit
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #14 –
Yahoo Message Number: 99676
Quote from: aq433"

"I assume you mean you've removed the Power supply section of the converter that both charges the battery and supplies 12V to run appliances and lights? And, that you have left the battery connected directly to the 12V fuse buss for the low-voltage circuits?"

Hi Steve,
 The converter has 2 output wires (+ & -).  I cut them, discarded the

converter, and wirenutted the remaining wire ends separately. So I did not
 change any wiring at the panel.  It's just like leaving the converter in

place, but not plugged into the AC outlet.

"If so, one thing to consider is how the output of your battery charger appears to your 12V circuits. It may have insufficient filtration and voltage regulation to prevent possible annoying artifacts on the 12V line that could potentially damage systems in the m'home. As inadequate the converter may be as a battery charger, as a 12V power supply, it was pretty well filtered, and maintained a safe voltage for all systems."

I have definitely not thought about this.  I never suspected the voltage

coming out of the charger.  I currently use an Everstart manual 6amp/2amp

charger.  I did measure the voltage of the under charged battery terminals

and it varried from ~14.5 to ~13.5.  I measured because I wanted to know if
 the charging voltage is high enough, and not to look for out-of-range surge

or drop.  Should I?  Aren't battery chargers supposed to regulate their

voltage as to not damage the batteries?  What about the chassis alternator's

voltage?
 Should I be worried?  One of my plan (nothing definite now) is to put a smart

25 to 40 amp battery charger in to replace the discarded converter.

Sam
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #15 –
Yahoo Message Number: 99677
Quote

 "Actually, ours has a several IC's, presumably comparators and zeners to ramp the output to the appropriate LED."

Steve
Geez, I just learned how to fill my tires and here you are talking about comparators and zeners!

Chris
Formerly: 2002 30' IB
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #16 –
Yahoo Message Number: 99735
Quote
or drop.  Should I?  Aren't battery chargers supposed to regulate their

voltage as to not damage the batteries?  What about the chassis alternator's

voltage?
Batteries don't need a filtered charger, although most chargers have a form of regulation, often rudimentary. Lack of filtration means the output could be simply half-wave rectified AC, which is simply allowing the positive peaks of the AC to pass through, after a transformer drops the voltage. A full-wave rectifier will fill in the gaps with positive peaks with a center-tapped transformer, providing a slightly smoother waveform. The battery itself, having a low impedance, will partially filter noise and ripple from the charger, but even a cheap converter will have filtered most of that out.
 The alternator output has ripple as well, and audio systems designed to be used with the engine running usually incorporate filters in the installation to eliminate 'alternator whine'. Most house systems in the RV are used with the engine off, so it is not a problem from batteries only, or a converter.

Steve
2004 FL
2013 Honda Fit
 
Re: Low voltage DC at all outlets, and other self inflicted problems
Reply #17 –
Yahoo Message Number: 99781
Quote
Batteries don't need a filtered charger, although most chargers have a form of regulation, often rudimentary. Lack of filtration means the output could be simply half-wave rectified AC, which is simply allowing the positive peaks of the AC to pass through, after a transformer drops the voltage. A full-wave rectifier will fill in the gaps with positive peaks with a center-tapped transformer, providing a slightly smoother waveform. The battery itself, having a low impedance, will partially filter noise and ripple from the charger, but even a cheap converter will have filtered most of that out.
Thanks, I will look carefully at the charger specs before buying.

Sam