Dual Battery Isolator or Solenoid? - Page 2 - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > Dual Battery Isolator or Solenoid?

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineOfficial Chassis Saver Rust Preventive Truck & Auto UnFS: 2007-2013 Jeep Wrangler "HALO" Angel Eye Kit

Reply
Unread 10-15-2013, 08:59 PM   #16
CSP
Registered User
 
Join Date: Aug 2002
Location: Colorado
Posts: 11,191
Quote:
Originally Posted by LumpyGrits View Post
You do know when one of the batteries have an issue. It will 'pull' the other down also.
That depends entirely on how it's wired, which is why Matt is asking the questions he is asking. Post #2 in this thread covered that already.

CSP is offline   Reply With Quote
Unread 10-15-2013, 10:20 PM   #17
Matt1981CJ7
Web Wheeler
 
Matt1981CJ7's Avatar
1981 CJ7 
 
Join Date: May 2011
Location: Elbert, CO
Posts: 9,446
Well, well, maybe ol' Lumpy actually learned something tonight.



Matt
Matt1981CJ7 is offline   Reply With Quote
Unread 10-15-2013, 10:37 PM   #18
WSS
Ps:91
 
WSS's Avatar
1972 CJ5 
 
Join Date: Oct 2012
Location: Chino, Ca
Posts: 1,990
Another reason for dual batts is a welder. I am right in the middle of a dual batt upgrade, it is turning out to be bigger $$ than I had hoped. I am going with the jeephammer write up here (mostly):

http://www.jeepforum.com/forum/f8/du...lding-1231432/

I like the "lend power" and "weld yoke" options he covers. I found a readywelder II on CL for cheap, hardly used and I bought 12 sb175 anderson connectors to do the connecting of things. I will also put a anderson out on the bumper for jumpers and cut my jumpers to be 13' and 2', this way I can still have regular cables but also have them hook right in the front.

For battery trays, I have seen some on ebay for the optimas. I like optimas, have had them for many years. I'm not against good products made in Mexico, I would prefer good products made in U.S.A. The reality is they have had problems but it seems limited.

I am probably going to draw a dxf of a dual battery tray and cut it myself, I will post it in the CJ drawings thread when I get it right.
__________________
www.metaltechus.com

Our Yellow 72 CJ5 build thread

Yellow Jeep club member #73802
WSS is offline   Reply With Quote
Unread 10-15-2013, 10:52 PM   #19
Matt1981CJ7
Web Wheeler
 
Matt1981CJ7's Avatar
1981 CJ7 
 
Join Date: May 2011
Location: Elbert, CO
Posts: 9,446
WSS,

I was considering Option #3 on Hammer's thread, before I decided to go the isolator route.

The welder and "lend power" features of his Option #4, while cool, would have been overkill for me.

Keep us posted on your progress.

Matt
Matt1981CJ7 is offline   Reply With Quote
Unread 10-16-2013, 12:30 AM   #20
jeep_boy02
Registered User
1980 CJ7 
 
Join Date: Dec 2012
Location: Neosho, Mo.
Posts: 130
Yes I just seen the lithos on last weeks "trucks" iirc. Seems like nice xtra power and the "push button reserve" is cool
jeep_boy02 is offline   Reply With Quote
Unread 10-16-2013, 01:06 AM   #21
WSS
Ps:91
 
WSS's Avatar
1972 CJ5 
 
Join Date: Oct 2012
Location: Chino, Ca
Posts: 1,990
Quote:
Originally Posted by 5-90 View Post
I think much depends on your anticipated use.

If you want something that will work with minimal to no intervention, and you'll be wiring accessories to the secondary battery directly, you can use a solid-state isolator (i.e.: Hellroaring - I've gotten the most consistently positive reports from the field on their units,) wire it up, and forget about it.

If you want a flexible system where you have to keep track of what's going on, go with a constant-duty solenoid (what rating depends on a number of factors.) However, a CD solenoid allows you to wire up batteries en banc and use a trigger lead from the vehicle to automate switching, you can wire in an "override OFF" switch (to cut out the secondary battery entirely, in case it goes flat and you need to start without interference - or it goes dead, and you need to just cut the thing out until you replace it,) an "override ON" switch (so you can self-jump, with a good accessory battery,) and you probably have more flexibility in terms of how you can add, configure, and use more than one additional battery.

Thumb rules for multiple batteries:
- Batteries wired directly en banc (constantly connected in parallel) must be of the same type, capacity, and age (as evidenced by the manufacture date code tag on the battery case.)
- Batteries of dissimilar types, capacities, or ages must be "isolated" from each other when not under charge, or you get "duelling battery" syndrome (the stronger battery tries to charge the weaker, the weaker doesn't accept the charge, and both batteries end up flat - with the possibility of being wrecked.)
- Banks of batteries may have different numbers (for instance, one starting battery and three deep cycle auxiliaries,) but the provisions in the previous two points must be observed (the three deep cycles must be the same type/capacity/age, or be isolated from each other. This may be a case of "mixed isolation" - the starting battery is isolated from the deep cycle bank by a solid-state isolator, the deep cycle batteries may be manually isolated from the rest of the bank by switched solenoids. This allows you to cut out a "dead" deep cycle and preserve the capacity of the other two - but the three should still be replaced all at once.)

A "solid-state" isolator is essentially a high-current diode pack/network. A diode is, simply put, a "one-way valve" for electricity, similar to a "check valve" as used in fluid power. Like a check valve, a diode will have limitations on reverse voltage (pressure) and current in either direction (flow,) and the higher those two specifications are, the more they cost.

A constant-duty solenoid is essentially a regular manual valve - it allows full flow in both directions, when the terminals are closed.

N.B.: A "Ford starter solenoid" is not a constant-duty solenoid! I know RVers have been using them for years as "isolators" - they're cheap and readily available. But, they never seem to understand why they have to replace them every six months, when the coils burn out (no matter how patiently I tried to explain it to them, back when I was holding down a parts counter...)
5-90, I have read your post here and am not understanding a few terms. I googled "en banc" and it is a French legal term LOL. I see you have a fair bit of knowledge on the subject and I would like to understand completely.

When you say "cut", does that translate to "open" line/switched off?

Does flat mean dead?

Whats a trigger lead?

Sorry to be tediuous! I am putting together all my parts right now, I should be building this system next week (If "work" does not get in the way). I am not clear on what my best option is, isolator or CD relay (solenoid). I will need 24v to weld and I would like to be able to put both batts to work during winching.

My CJ currently has a yellow Opitma (deep cycle) that is two years old, should I try to find one the same age (easy actually, my local oreillys has one that has been there at least that long)?

Matt, sorry to seem hi-jacky.
__________________
www.metaltechus.com

Our Yellow 72 CJ5 build thread

Yellow Jeep club member #73802
WSS is offline   Reply With Quote
Unread 10-16-2013, 06:40 AM   #22
Matt1981CJ7
Web Wheeler
 
Matt1981CJ7's Avatar
1981 CJ7 
 
Join Date: May 2011
Location: Elbert, CO
Posts: 9,446
WSS,

As I understand it, one of the benefits of using a battery isolator/combiner is you don't have to use identical batteries of similar age. And, since it only allows power to flow in one direction, you don't have the parasitic run-down that Lumpy mentioned. Someone please correct me, if I'm wrong.

With a flip of a remote switch, you can either "combine" the batteries to double cranking and winching power. Or, you can "isolate" one of the batteries as a dedicated backup.

Matt
Matt1981CJ7 is offline   Reply With Quote
Unread 10-16-2013, 08:03 AM   #23
dhubbs
Registered User
1979 CJ5 
 
Join Date: Sep 2011
Location: mitchell, ne
Posts: 145
That is pretty much exactly what it does. We used to have them factory installed on some of our older fire trucks from the early seventies. Their main function was to have a redundant power system in the event one failed. On our old snorkel aerial truck, the hydraulic system had an electric backup pump. Using the isolater gave an additional option for using the electic pump to at least get the bucket back to the ground if you had a mechanical or electrical failure. We had a selector switch on the dash for battery bank A, battery bank B, or Both. Having the isolater proved very handy on more than one occasion. But we did keep the 1971 snorkel in service until just two years ago.
dhubbs is offline   Reply With Quote
Unread 10-20-2013, 12:08 AM   #24
WSS
Ps:91
 
WSS's Avatar
1972 CJ5 
 
Join Date: Oct 2012
Location: Chino, Ca
Posts: 1,990
Quote:
Originally Posted by Matt1981CJ7 View Post
WSS,

With a flip of a remote switch, you can either "combine" the batteries to double cranking and winching power. Or, you can "isolate" one of the batteries as a dedicated backup.

Matt
Matt,

What does the remote switch control? The isolator or a seperate hi-amp relay (solenoid)? I just bought a NOCO 140 amp relay, it is bigger than I had hoped but it will fit under the tray, so no huge deal.

Anyone have any comments about the brand?

WSS
__________________
www.metaltechus.com

Our Yellow 72 CJ5 build thread

Yellow Jeep club member #73802
WSS is offline   Reply With Quote
Unread 10-20-2013, 12:19 AM   #25
Matt1981CJ7
Web Wheeler
 
Matt1981CJ7's Avatar
1981 CJ7 
 
Join Date: May 2011
Location: Elbert, CO
Posts: 9,446
The remote switch operates the isolator/combiner. There is no need for a solenoid with this system, just the isolator, an extra battery, and some cable. The isolator is about the size of a ICM box.

I got tired of waiting on a backordered tray, so I built my own dual-battery tray today. It turned out nice. I'll post up some pics, here, in the morning.

Matt
Matt1981CJ7 is offline   Reply With Quote
Unread 10-20-2013, 12:48 AM   #26
WSS
Ps:91
 
WSS's Avatar
1972 CJ5 
 
Join Date: Oct 2012
Location: Chino, Ca
Posts: 1,990
Quote:
Originally Posted by Matt1981CJ7 View Post
The remote switch operates the isolator/combiner. There is no need for a solenoid with this system, just the isolator, an extra battery, and some cable. The isolator is about the size of a ICM box.

I got tired of waiting on a backordered tray, so I built my own dual-battery tray today. It turned out nice. I'll post up some pics, here, in the morning.

Matt
ah, you went with the hellroaring I/C? It will switch hi-amp loads?

Pics please, of the tray.

Cheers!
WSS
__________________
www.metaltechus.com

Our Yellow 72 CJ5 build thread

Yellow Jeep club member #73802
WSS is offline   Reply With Quote
Unread 10-20-2013, 04:29 AM   #27
Matt1981CJ7
Web Wheeler
 
Matt1981CJ7's Avatar
1981 CJ7 
 
Join Date: May 2011
Location: Elbert, CO
Posts: 9,446
Mornin' gentlemen,

My dual-battery tray uses the original single tray (slightly modified) and all the original supports. I only had to drill one new hole in the firewall. Here's how:

1. First, I removed the old tray and cut off the outside support and the clamp-down bracket. Then I flattened the 1/4" lip on the front and outer sides of the old tray. (sorry for the bad pic)

2. I marked and cut the new tray from some scrap sheet metal.

3. I bent the lips on the new tray, then welded on the support that I cut off the old tray.

4. I painted both pieces with some VHT paint that I had leftover from my engine build.

5. Pic of both halves married together.

Total cost of my new tray was about three hours of my time. That's a far cry better than $199 that Q-tec wants for their tray. My next task is to make new battery cables.

Matt
dualbatts3.jpg

dualbatts1.jpg

dualbatts2.jpg

dualbatts4.jpg

dualbatts5.jpg

Matt1981CJ7 is offline   Reply With Quote
Unread 10-20-2013, 07:20 AM   #28
Matt1981CJ7
Web Wheeler
 
Matt1981CJ7's Avatar
1981 CJ7 
 
Join Date: May 2011
Location: Elbert, CO
Posts: 9,446
Installed, with batteries in place and a heavy-duty bungee strap for a hold down.

Matt
dualbatt6.jpg

Matt1981CJ7 is offline   Reply With Quote
Unread 10-20-2013, 07:58 AM   #29
gmakra
Registered User
1985 CJ7 
 
Join Date: Jun 2008
Location: Chicago area
Posts: 2,498
Matt I would turn the outboard battery so the posts match the inboard one, the possibility of your positive terminal grounding out to your hood is there.
And I would ditch the Bungee for something a bit solid ie J bolts with a metal strap across the top
Other wise it looks pretty good and when you factor that your an architect into the equation its outstanding!
gmakra is offline   Reply With Quote
Unread 10-20-2013, 08:52 AM   #30
keith460
Jeep. There's Only One
 
keith460's Avatar
1984 CJ7 
 
Join Date: Jan 2007
Location: Doylestown, PA
Posts: 4,504
I just helped wire my friends 25ft boat this summer that had dual batteries and we discovered the redundancy electrical system it had. It has a simple isolator/combiner that works off of a simple dash toggle switch. In the event of a battery failure, simply toggle the switch and use the other battery. Worked great and my friend cursed himself for buying batteries that he did not need to buy due to not knowing what the isolator did and poor corroded wiring.

That's a nice dual battery tray you made their Matt. You should have them made and sell them.
__________________
.
1984 CJ-7 Renegade
__________________

Restoration Thread:http://www.jeepsunlimited.com/forums...d.php?t=434226
keith460 is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.