Reply
 
Thread Tools Search this Thread Display Modes
 
Old 02-03-2007, 02:30 AM   #1
Rivet Master
 
SilverGate's Avatar

 
2007 23' Safari SE
San Diego , California
Join Date: Apr 2006
Posts: 1,490
Battery Disconnect Switch, Solar & AGMs

Currently have the ’07 Safari plugged into shore power between trips…
It’s parked in the home driveway (its home).
We are in and out of it each day… and like keeping items in refrig cold.

It has 2, 53-watt factory-installed Solar Panels & 2 AGM batteries…
And a 600-watt inverter.

The Battery Disconnect Switch is currently on.
Should this switch be turned off?
If left on, is there a danger of the Glassmatt batteries getting overcharged?
When should it be turned off (other than when placing in storage)?

Any other concerns that I should have with this set-up?

Thanks
SilverGate
__________________

__________________
SilverGate is offline   Reply With Quote
Old 02-03-2007, 06:27 AM   #2
Rivet Master
 
boatdoc's Avatar
 
1973 Argosy 26
Norristown , Pennsylvania
Join Date: Sep 2006
Posts: 644
Images: 1
Arrow Battery disconnect switch.

Quote:
Originally Posted by SilverGate
Currently have the ’07 Safari plugged into shore power between trips…
It’s parked in the home driveway (its home).
We are in and out of it each day… and like keeping items in refrig cold.

It has 2, 53-watt factory-installed Solar Panels & 2 AGM batteries…
And a 600-watt inverter.

The Battery Disconnect Switch is currently on.
Should this switch be turned off?
If left on, is there a danger of the Glassmatt batteries getting overcharged?
When should it be turned off (other than when placing in storage)?

Any other concerns that I should have with this set-up?

Thanks
SilverGate
Hi Silver Gate; The ultimate decision is yours, since you are the one who can control it. If you have a battery condition monitor [voltmeter panel] you should maintain a charge until batteries are at 13.5 volts. With dual batteries you should have either two voltmeters, or one with a two way switch so that you may check the status of each battery individually. This will depend on type of the on board charger you have. Some chargers have no shut off feature, and they can overheat the batteries by overcharging them, which is especially detrimental to AGM batteries. Marine Chargers International, manufacture Solid State chargers such as Dual Pro. [best we have used]Those chargers have LED display showing the condition of each battery individually. Each charge bank, charges each battery independently. They are not crossed over, as one as some other chargers are. They have a shut down feature once the battery reaches 13.7 volts. Your solar charger should not be a threat to your batteries because they depend on light, and do not provide high rate of charge to overheat batteries. Your concern should be with on board charger. If the voltage in your batteries stays above 13.5 volts you should install a charge cut off switches to each battery so that you may control the battery charge on individual basis. Try to imagine a battery as a storage container. The bigger container the more it can store. What this container stores is the amperage, which is volume. The voltage however in that container is the pressure, which is limited to 13.75 volt. If you try to over pressurize that container you will first create heat, or container can explode from being over pressurized past it's capacity. This is why you need to monitor them with a good voltmeter. Hope this is helpfully with your concerns. Thanks "Boatdoc"
__________________

__________________
boatdoc is offline   Reply With Quote
Old 02-03-2007, 06:40 AM   #3
Rivet Master<br><img src="/ugala/forums/images/5rivet.gif">
 
CanoeStream's Avatar

 
2006 25' Safari FB SE
St. Cloud , Minnesota
Join Date: Aug 2003
Posts: 13,279
Images: 19
Blog Entries: 3
The inverter & solar setup shouldn't be variables in this question. It comes down to your converter -- Parallax model? I'm trying to think back here (-14F outside this AM, so been a few months... ). A modern converter shouldn't overcharge & boil batteries like the Univolts of old. When plugged in to shore power I know the monitor light by the door is on whether I turn on the switch or not. So the question remains -- does that switch really isolate the convertor & batteries if you're plugged in? Here's how you find out: turn on your ceiling lights -- they're all 12 volts and if they're working your converter is also operating. Please report back for both states of the switch -- open & closed ... pretty please?

At the price of Dometics and insignificant price of small refrigerators, I'd almost spring for a couple of cheapo dorm fridges before I kept my Airstream fridge going all year. That's just me ... unless I was constantly having driveway parties!
__________________
Bob

5 meter Langford Nahanni

CanoeStream is offline   Reply With Quote
Old 02-03-2007, 08:56 PM   #4
Rivet Master
 
SilverGate's Avatar

 
2007 23' Safari SE
San Diego , California
Join Date: Apr 2006
Posts: 1,490
Electrical Experiments...

Thank you boatdoc and Canoe stream for your comments.

Here is more data re: my electrical system and experiments:
2 Glassmatt Batteries, factory installed.
2, 53w Solar Panels, factory installed

My Parallax Power Converter is Series 7300…
Manual says it’s the most advanced 120v to 12v converter system available today.
It says it will deliver the full rated output to the batteries, if needed, but will taper off to a few hundred milliamps when the batteries are at full charge.

My dealer tells me the Solar Power Controller (Sunexplorer) will stop charging the battery when the batteries are at full charge.

The few days after I first brought the trailer home I enjoyed watching the Solar Power put out about 3.7 amps or so and the battery gradually went from 65% to 95 – 100%
I watched the daily fluctuations as the sun and cloud patterns varied.
Then I got thinking about that Battery Disconnect switch and read the manual.
So I turned it on and, of course, the battery immediately showed 100% & stayed that way. And I left the switch on for about a week until this afternoon… and did some experiments:

First, while the switch was still on, "In Use", I got the following readings:
At 1:40 p.m.:
MicroPulse Systems Monotor: Battery Full
Sunexplorer Monitor: Battery 100%, 13.7v, .0 Solar Charge amps, 326 Solar Amp hrs.
At 1:41 p.m., I turned the Battery Disconnect Switch to off, "Store" and read:
Systems Monitor: Battery Full
Sunexplorer Monitor: 100%, 13.6v, .0 solar charge amps
1:46 p.m.: " " 100%, 13.4v, " "
2:05 p.m. " " 100%, 13.3v, " "
2:51 p.m. " " 100%, 13.2v, " "
4:50 p.m. " " 100%, 13.1v, " "
5:30 p.m. " " 100%,13.1v, " "

Canoe stream – Following are the results of the test that you suggested:
While still connected to shore power (30 amp), I was able to turn on the overhead Halogen lights while the Battery Disconnect Switch was both on and off.
When the shore power was disconnected, the Halogen lights would turn on if I turned on the Battery Disconnect Switch (to "In Use"), but the lights would not turn on when the switch was turned off ("Store").

Discussion: Looks like everything is operating correctly. When I first turned the Battery Disconnect Switch off today (after it had been on continuously for about a week), the battery was fully charged to the max.: 13.7 volts. The Solar Power Monitor showed a gradual decrease of voltage through the afternoon today, from 13.6 to 13.1 volts. It also showed the battery to be at 100% throughout the afternoon and the .0 amps of Solar Charge reflects that the Solar Monitor "knew" that the battery did not need recharging yet. When the Battery Disconnect Switch is turned off, the battery only gets recharged by Solar Power. Certain items such as the CO and LP Gas detectors slowly drain the battery.

Outcome: I will continue to use shore power and will leave the Battery Disconnect Switch turned off and monitor the status of the battery on a daily basis. If the battery gets down to about 65% (say on days that there is little sunlight), I will then turn on the Battery Disconnect Switch.
On nights with thunderstorms, I’ll send up the kite on a wire and wait to exclaim:
"It’s Alive… It’s Alive!"

Thanks for your comments and I invite a discussion here.
SilverGate
__________________
SilverGate is offline   Reply With Quote
Old 02-07-2007, 01:15 AM   #5
Rivet Master
 
SilverGate's Avatar

 
2007 23' Safari SE
San Diego , California
Join Date: Apr 2006
Posts: 1,490
Battery Disconnect Switch Should Be Left On!

After consulting with another very knowledgeable and experienced AS owner, I learned that:
  1. The Parallax power converter automatically reduces the charging current after 13.5 volts to prevent battery overcharging when plugged in for long periods. There is no danger to the battery. I can also leave it unplugged since my solar panels will keep the battery at full charge easily while the trailer is not in use, unless I have a weeks-long cloudy spell. (Which is unlikely in San Diego).
  2. I should leave the Battery Disconnect Switch in the normal on or "In Use" position. It is to be used (in off or "Store" position) when I have to remove the batteries or do service.
  3. I can leave the fridge on if I want. It is designed for long term use. Many people never turn theirs off. (The person I consulted has had his on continuously for 16 months so far.) Of course, I will be curious to see what my new electric bill will be!
  4. Since I have solar, switching the Disconnect to "Store" does nothing for me. For people without solar, the switch gives them a way to eliminate "phantom loads" from draining the battery during storage. Phantom loads include tiny electrical drains in the radio, and the propane leak detector. These aren't a problem in my case, because my batteries will stay charged regardless.
  5. With the battery disconnect in "Store" position, I might not be able to run my refrigerator.
  6. With the battery disconnect in "Store" position, my propane leak detector will not work. That eliminates a useful safety feature, and also I will find that after long periods of storage, the leak detector alarms when I turn the battery back on. See your Owners Manual for details on that.
So there's no advantage to me in disconnecting the batteries, but there are a few downsides!

Silvergate
__________________
SilverGate is offline   Reply With Quote
Old 02-07-2007, 08:01 AM   #6
3 Rivet Member
 
B25guy's Avatar
 
2003 25' Safari
Yakima , Washington
Join Date: Aug 2003
Posts: 153
Images: 20
that store/use thing again...

Silvergate,

Glad to hear you're enjoying your new coach...lots to learn but well worth the adventure!

I've wrestled with a similar issue and posted previously but thought this a good time to summarize in case you were wondering (looks like you might be). I don't have solar but everything else the same.

After a roughly 3 years of life out of my coach batteries, I had to change them out last fall. In doing so, I was trying a couple of different experiments to try and understand just how the charging system works and exactly how the store/use switch fits in (I had odd battery behaviour earlier).

At first, I was under the impression that when I was plugged into shore power and the red light was on, I was also charging the batteries...not necessarly so...read on...

I knew the converter/charger (Parallax 5500) was working because during the final days of my batteries, the 12v lghts were real dim until I plugged in shore power. But remember, the 110v comes directly into the converter/charger then feeds all the 12v circuits, including the lone red wire snaking to the front of the coach to charge the batteries. If you follow that wire, both phyically and via the wiring diagram, you'll see that it goes through a switch/solenoid...the store/use feature!

Part of my experiment was to see why when I plugged into shore power (again with the dying batteries), the lights would brighten, everything worked just fine but when I disconnected after a few hours, the 12v lights would go real dim again. Just really dead batteries, wouldn't hold any charge???

Get the volt meter out and see what's going on here...

Here's the set-up:

Coach is standing by itself, nearly dead batteries. No shore power, store/use is off (red light off), no 12v lights come on at all (of course). Meter on the batteries shows 10-11v, not good. Plug in shore power, store/use is on (light is on, but I didn't touch the switch), 12v lights are bright. Meter on the batteries shows 10-11v and not climbing! Flip open the converter cover and measure charging output (I think on lug D) for 12v going to the batteries...yup, 13+v going.

For grins, I cycle the store/use to off (red light doesn't go off, but hear an audible clicking) then back on again...nothing changes inside, lights still on bright...meter on batteries...13+v now going to batteries!!!!!!

When I discovered this, I thought something wasn't right as I didn't see anywhere in the manual that this cycling of the store/use had to happen in order for the batteries to charge. When I posted earlier, nobody else seemed to experience the same behaviour or hadn't found the need to check.

I had gotten into the habit of turning off the store/use whenever towing or leaving for a long afternoon and certainly while parked at home (again to eliminate the phantom loads as you described) and assuming that whenever I plugged into shore power, batteries were automatically being charged (and of course while towing, there was a 12v charge going back there too).

Considering my habit, I don't think I was charging when I thought I was and further explains why there were some outings the batteries didn't seem to have the storage and others it did (dying batteries normally die linearly...in other words, hold less and less a charge until terminal).

Unless anybody tells me that they are getting 13+v to the batteries following the same set-up above, I'll assume my converter/charger/store/use is working as normal and all I need to do is know this peculiarity.

Maybe more info than wanted but thought somebody could benefit.

Marc
__________________
B25guy is offline   Reply With Quote
Old 02-07-2007, 12:51 PM   #7
Rivet Master
 
SilverGate's Avatar

 
2007 23' Safari SE
San Diego , California
Join Date: Apr 2006
Posts: 1,490
Battery Disconnect Switch

Thanks, Marc, for sharing your experiment and observations.

First, at least in my set-up when connected to shore power, the Battery Disconnect Switch red light is on (lit) no matter whether the switch is actually in "Use" (on) position or "Store" (off).
An audible click will be heard when switching from "Use" to "Store" and vice versa.

Second, for the record, my 2007 AS Owners Manual says:
"The disconnect switch is used to separate the batteries from the 12-volt distribution panel and converter charging system.

When the switch is turned "Use" (on) and the trailer is plugged into a 110-volt shoreline, the 12-volt distribution panel will receive power from the converter and the batteries will be charged through the converter charging system.

When the switch is turned to "Store" (off) and the trailer is plugged into a 110-volt shoreline, the 12-volt distribution panel will still receive power from the converter, but the batteries are disconnected from the system. The batteries will not be drained with the switch in the "store" position. The converter will not charge the batteries with the switch in this position.

The charge in the 12-volt batteries is replenished when towing from the tow vehicle alternator through the 7-way cord. This charge will go to the batteries no matter which position the Battery Disconnect Switch is in."

So, Marc, the Battery Disconnect Switch red light is not an indicator of whether the switch is actually in "Use" or "Store" position. The Battery Disconnect Switch needs to be on "Use" for your batteries to get charged when connected to shore power.

In my experiments, I found that the Battery Disconnect Switch does not separate my batteries from my Solar System (2, 53-watt Solar Panels). So in my set-up, even if the Battery Disconnect Switch is in the "Store" position, my AGM batteries will get charged by my Solar Panels… which is one of the benefits of having Solar!

SilverGate
__________________
SilverGate is offline   Reply With Quote
Old 02-07-2007, 01:35 PM   #8
Round on both ends
 
SafeHarbor's Avatar
 
1979 31' Excella 500
1975 28' Argosy 28
Rutledge , Georgia
Join Date: Apr 2005
Posts: 783
Images: 39
About the fridge

I'm a firm believer in letting amonia-cycle fridges cycle as a means of keeping them going for a long, long time.

My ancient fridge has a 175-watt heating element. I don't know what the actual percentage of run-time is on it, but the enclosure around it is always warm to hot when I check it, even in very cold weather.

The fridge in my Argosy has been running since I got it in 1992. I've replaced one heating element. The fridge in the Excella has been operating since I got it in 2005. Right on schedule, the heating element promptly died a week after I got it.

I have no experience with the modern fridges with their boards and other saftety features, but the amonia-cycle principle is still the same. You need to keep them circulating.

Lamar
__________________
1975 Argosy 28 "Argosy"
1979 Excella 500 31 "Betsy"
1992 Lincoln Mk 7 LSC
2003 Dodge 2500 Cummins "TowHog"
"Lucy Loosehair" the cat - Airstream mascot
Klaatu barada nikto
SafeHarbor is offline   Reply With Quote
Old 02-07-2007, 01:46 PM   #9
3 Rivet Member
 
B25guy's Avatar
 
2003 25' Safari
Yakima , Washington
Join Date: Aug 2003
Posts: 153
Images: 20
the light just came on!

SilverGate,

Thanks for confirming my observations.

My confusion came from the fact that whenever I'd plug into shore power, the red light came on (assuming I had turned it to "store" previously), giving me the impression that the charger to battery connection had been made. I never verified what it really was doing until last fall.

I now know that when I do cycle the switch to "store", the solenoid clicks and disconnects the charge line from batteries as you stated (if on shore, red light stays on, if off shore, red light goes out...perfect)

I am getting the distinct impression that my model year might have used a different switch than others because I cannot ever have the red light go out by switching to "store" while on shore power (no real reason to do this, but possible as you stated). My switch is a center neutral position with a momentary on in either "store" or "use"...you cannot tell by looking at it that it is in either position (red light being irrelevant...it is on when on shore power, period!).

And finally, if I left the switch in "use" and then unplugged from shore power (red light stays on, of course), traveled on, then plugged into shore power again, it stayed in "use"...simple (and this is probably why a lot of others haven't ganged up on me to say "hey stupid...."). I'm an engineer and a helicopter pilot so I just have to know all these use cases???

Marc
__________________
B25guy is offline   Reply With Quote
Old 02-07-2007, 02:22 PM   #10
Rivet Master
 
clancy_boy's Avatar
 
2003 22' International CCD
Kiln , Mississippi
Join Date: Dec 2005
Posts: 2,780
Images: 8
This confusion over the light on or off and what has power and ghost usage by the appliances is the reason I put a marine battery disconnect inline to the battery. I mounted it to the cross member that supports the battery and it sits below the front frame. This way, when I flip the switch , I know the battery is disconnected. It also shuts off the electric jack so that I don't have to worry about that while it's stored on my drive. I leave mine plugged into the shore power and only have the lights used when I need it. Fridge, streio, TV are all turned off. I don't believe there is an issue with the charger plugged in like this. Anyone have any other ideas on that?
__________________
Michael & Tina with Layla and Preston BZ
The family has grown.
2003 22' INTERNATIONAL CCD
clancy_boy is offline   Reply With Quote
Old 04-10-2007, 05:37 PM   #11
Rivet Master
 
tsunami's Avatar
 
2016 28' Flying Cloud
Brandenburg , Kentucky
Join Date: May 2006
Posts: 840
Images: 20
Question

Opened the door on my AS, reached around and flipped the switch to take the coach out of storage. Turned on the lights, they lit up for a couple seconds and then went out. I have the AS plugged into a 110v 20A circute. I checked my "shore power", it's OK and I plugged a 110v fan into a couple of outlets in the AS and it worked fine. Does anyone have any suggestions ? Thank
__________________
tsunami is offline   Reply With Quote
Old 04-10-2007, 05:49 PM   #12
Rivet Master
 
tsunami's Avatar
 
2016 28' Flying Cloud
Brandenburg , Kentucky
Join Date: May 2006
Posts: 840
Images: 20
Answer

Called an AS dealer and they told me that the batteries are run down which caused the "store/use" switch to stay in the storage mode. I was instructed to put a battery charger on for about 1 hour and this would allow the swicth to take the coach out of the storage mode. He recommended that I leave it plugged into the 110v circute for a couple days...
__________________
tsunami is offline   Reply With Quote
Old 04-10-2007, 06:19 PM   #13
4 Rivet Member
 
2007 25' Safari FB SE
Blaine , Washington
Join Date: Jan 2007
Posts: 291
The carbon monoxide detector stays on no matter what. This will run the batteries down in about 3 to 4 weeks in storage.
__________________
Relentless is offline   Reply With Quote
Old 04-11-2007, 02:19 AM   #14
4 Rivet Member
 
Motoman's Avatar
 
2005 25' International CCD
1960 18' "Footer"
1959 26' Overlander
Riverside , California
Join Date: Oct 2006
Posts: 334
Images: 3
I am going to disagree with Silvergate. The Parrallax system will over charge the batteries when left connected to shore power. We have the same model in our 25' CCD and over a month or so the liquid level in the batteries would drop to expose the plates. I had a discussion about this with one of the engineers from Parrallax when I installed solar power on our Airstream. He told me that the Model 7300, actually a series designation since the model number inside the unit is 7355, is designed to provide 13.8 volts to the low voltage equipment up to its rated capacity of 55 amps. it is a two stage charger so it reduces charge current to a few hundred milliamps to the battery when is charged and there is no load but it will not reduce voltage enough to avoid overcharging the batteries. They recommend that the user disconnect the batteries when plugged into shore power and periodically connect the batteries every week or so for a day to ensure they are maintained at full charge.

You can continuously monitor the liquid level with conventional acid batteries and try to avoid damage but a long term charge at a few hunderd milliwatts will generate heat in the battery and result in a loss of water from vapor driven off. It is more serious in AGM or true gel battereis because we cannot add distilled water to replenish them.

There are converters that do offer a three stage charge , bulk to bring the battery up to 14.4 volts, then power is reduce for the adsorbtion phase at approximately 13.6 volts as a finishing charge after which it goes into a float mode of approximatley 13.2 volts to ensure that water is not gassed off from the cells. Best Converter makes this type of charger and even makes a conversion kit to change out the charge controller in the Parallax converters to one with a three stage charge system. They also sell a new model Multistage 55 Amp Parallax ParaMode Converter/Charger with Temperature Compensation that reduces the float voltage so that the battery isn't overcharged in warmer weather. It did appear that the newer Parallax ParaMode Converter/Charger requires a separate 12 volt DC fuse block since noen seems to be built into the unit like the model 7300 series. See their web site for info on both the conversion kit and the nwere Parallax converter, BestConverter - Inteli-Power Converters, Inverters, Solar Chargers .

Some people believe that the three stage systems can be fooled into charging at the higher bulk charge rates by voltage drops under load while two stage charge systems are not. I found some info on that at Battery Chargers - Which One's For You - DonRowe.com .

With solar power your panels and solar charge controller are connected directly to the DC battery buss inside the trailer so the batteries will be maintained by the colar system even when disconnected and connected to shore power. Read up on the issues and make your own decision. I am staying with my Parallax system but may opt for the conversion to three stage charging once I have studied it some more. Supposedly a good book is "Managing 12 Volts" by Harold Barre.
__________________

__________________
Don (KD6UVT) & Gail Williams

What do you want to be in life, a spectator or a participant?

SNU #157
FCU #004
Motoman is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
New battery selector switch FrankR Electrical - Systems, Generators, Batteries & Solar 6 02-08-2013 07:34 PM
igniton switch and the mystery of the dead battery Curtis-79MH Airstream Motorhome Forums 3 10-25-2002 03:58 PM
Solar battery charging Charles Q Treichel Generators & Solar Power 23 10-17-2002 11:22 AM
Battery Dead/Power jack question jcanavera Jacks, Stabilizers, Lifting and Leveling 34 08-16-2002 02:51 PM
Auto Battery problems.... kzener40 Airstream Motorhome Forums 10 08-05-2002 07:37 PM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 07:19 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.