Battery Isolators,Separators, and Switches?

[wltrmtty]

I am now properly overwhelmed. I recently purchased a 1998 SMB built on the E250 chassis. I have a van battery and two house batteries. The van battery died on the previous owner, so they installed a keyed cut-off switch on the van battery's ground. Before starting the van, the ground is engaged. I did find a Sure Power isolator on the driver side engine compartment and assume it's stock. I'm assuming from the previous discussions, this isolator has failed. This is what I'd like to do:
* Have an isolator system that allows me to remove the keyed cut-off.
* Install a 180 Watt Zamp portable solar system with integrated 15A controller. I thought I could just hook this up to the house battery; positive on the nearest house battery and the ground to the battery on the other side of the van.

After reading (nay, slogging) through this thread, I am not sure I know what to do or if I can do it. I live in SE Wisconsin and would consider having a local RV mechanic so the work, but not surer if there's one nearby that understands SMB.

Suggestions? Thank you for the help!

Terry

[Scalf77]

Terry,
These are all doable things, I suspect you would need to go to a shop. A isolator or separator install is pretty much the same on a SMB as other class-B's. The biggest problem with SMB is everything is pretty tight as far as install space. The easiest thing to do would be to replace the surepower isolator with another. The voltage drop issue of the diodes depends on if feedback for alternator is before or after the isolator. I am not sure about a 1998, myself but I am sure others on the forum may know.

The next option would be an ACR or Automatic Charging Relay. There are a couple that I would recommend that are like the Surepower 1315-200 referenced in this thread, but quite frankly just better. The choice here depends on a couple of things Alternator Size, and if you want't to be able to emergency jump start from house batteries.

The Blue Sea 7610 SI-ACR Automatic Charging Relay

The 7610 will handle up to 120 amp alternators, so if your alternator is larger than that I can't recommend it. You can wire in start isolation and a indicator LED, but this unit will not provide emergency jump start. Also if choosing this unit take care in choosing the wire size, they generally recommend larger capacity wire for the actual current . You definitely need to replace the existing wires.

Blue Sea 7622 ML-ACR Automatic Charging Relay with Manual Control

The 7620 & 7622 pretty much perform the same, the difference is the 7622 will let you manually open and close the relay, it doesn't cost much more.

The 7622 has more than enough capability for are setups, it also comes with a remote switch, that will allow you to operate in there modes: Disconnected, Auto, and Connected. The most common mode is auto, the switch will also provide LED indication to the state of the ACR and some diagnostic information.

By switching the remote switch connected you can use it for a start assist mode, or emergency jump start.

You can than hook solar solution of your choice to your house battery or if you are interested in combined solution you may want to look at a combined solution. If have installed a couple of these units and to date customers are happy.

KISAE DMT-1250, The 1250 is the 50 amp version, they also make a 30 amp version. The DMT-1250 is a DC to DC charger, it will become a 3 stage charger for your house battery that will run off of your starting battery and alternator. You would not need an isolator, separator or ACR for this solution. While it will provide the isolation and charging functions of a ACR it does not have emergency jump start capability. It does have built in solar, so you could use it as your solar controller. Note: this means you would not need a portable panel with an integrated controller, but one with out.

Hope this helps, try looking into these and feel free to ask more questions. I am hooking one of the DMT-1250's into my own rig soon, and will provide a right up. Feel free to PM also.
-greg

[wltrmtty]

Thank you Greg. I will read this a couple times. I don't know what amp alternator I have, but NAPA offers 95, 130 and 200. I'd like to go with as much as possible as I read an article in a forum (may have been yours, I don't recall) that explained I need to size the alternator to the demand. If I am running the van a/c and the house a/c + listening to the radio, etc, there may not be enough amps to charge the house battery. I'd prefer the 200 amp, but then I believe that would burn out the isolator/charging relay.

Although not elegant, I'm thinking I will continue with the cut-off switch and tackle during the off season.

Thank you, again, for your help.

Terry

[jkolodzinski]

I have battery separator 1314-200 installed by Sportsmobile. Will this separator work for Li-Ion batteries?

[Scalf77]

It is not advisable to hook Li-Ion batteries directly to your alternator via a separator. Li-Ion tend to be current hungry and will burn up your alternator. It better to put a DC to DC charger between starting battery system and your Li-Ion system. Just look for ones that support the Li-Ion and more importantly that can be programmed to support the voltages your battery manufacturer wants. There are a couple of companies that make these, more everyday. Sterling Power has a complete line, KISAE makes a DMT1230 or 1250 which combines Solar controller and Alternator inputs, I am currently running this in my rig, but not on Li-Ion, I believe Renogy has one,I have no experience with. There are a few others I am leaving out.

-greg

[OutlawImages]

Appreciate the time given to share knowledge for those of us looking for it

Great article

[gahamby]

I have looked at all 18 pages and read those posts that seem relevant to my situation.
I have a 2007 GMC 2500 V8 6.0 RB50 SMB Indiana build.
The Sure Power 1315-200 is pre recall. S/N 07000056
No solar panels.
Since I have owned the van (fall '17) all the gauges drop to zero when the ignition key is turned to ACC and then start. There is the click of the isolater and the sound like a solenoid engaging from the drivers side front area.
After all this things seemed to run normally.
Just recently I had to jump start the van. It started and all seemed well. I was able to park over night running on house battery only.
On this last trip trouble ensued. The isolater got hot and was pulsing. The house battery didn't charge on the drive home. This with the fridge on and the Starcool running.
I plugged into shore power at home and the house battery charged. The van starts properly.
In all my reading of posts , I'm seriously considering changing out the Sure Power for a Blue Sea isolater.
I don't just want to throw new parts at the problem hoping for a fix.
What am I missing?
Thanks GH

[marret]

I wonder if the no power when the ignition is on ACC and start is for start isolation? This can be wired in for the Blue Sea ML-ACR isolater.

With the van running, is the house battery charging? You mentioned it did not on the drive home. Have you confirmed this with a meter? Power is making it to the isolater?

Recently I replaced my isolater, went with a new Blue Sea ML-ACR 7620 instead of bumping up to the 7622 because of the remote switch (see comments below):
https://www.bluesea.com/products/762...ay_-_12V_DC_1A that I bought from PKYS, happily while on sale.

If I remember correctly, my house batteries were no longer being charged by the van alternator. A voltage check showed that.

Also, I did notice the clicks changing toward the end. The clicks got louder and more frequent if that makes sense.

The new 7620 has a nice remote switch that allow on, off and auto. My old 7620 had a simple push button on the dash that I'm not sure worked and after looking at it, I wonder about the wiring SMB did on it. My isolater is under my gaucho right behind the drivers seat.

Sounds like you are right. I'd do another couple checks. Upgrading to the Blue Sea wouldn't hurt either.

[gahamby]

I too wonder at SMB's wiring. The hot line from the start battery to the isolater has a short jumper of #8 AWG that then splices to a run of #2 AWG that then connects to the large fuse lug in the box under the hood. It then travels back to the isolater. I'll try metering the house battery with the van idling.
Do your dash gauges all bang to zero when you turn the key on?
My house electrical is under the gaucho at the rear.
ps: thanks for the link. it looks like a marine supplier is a possible source. Amazon also lists them. More stuff to look into.
Is this the one?
https://www.amazon.com/Blue-Sea-Syst...gateway&sr=8-2

[Scalf77]

So, my first thoughts that come to mind, your starter is possibly going bad and/or your alternator. That may not be true, as your Surepower has most likely exceeded it's useful age.

When you say pulsing, it would be nice you no exactly what you mean cycle on 2 secs /off secs (need some time frame).

In any event the possible culprit is the solenoid for the Suerpower has reached it's 50,000 cycle usefulness. The unit is always warm when on (it's continuous duty) but if is getting real hot I would expect that there could be some contact resistance building up on the inside of the solenoid. Running Starcool can present some large currents needed to go across the Surepower unit along with the normal charge current. It could cycle based on the voltage being seen at the surepower terminal, goes above threshold and the unit connects, large load battery charge level and startcool cause it to fall below disconnect voltage and it disconnects. The alternator then goes back to producing load with out house system, and it goes above connect voltage and the cycle continues.

So it might be a good time to think of an upgrade. I didn't really follow the wiring you were trying to explain. The only real voltage it needs other than battery cables is ground. If you disconnect ground it will disable the unit, They most likely wired in the start assist circuit, if correctly wired that should go to the "start" circuit. There are various ways that sportsmobile has done, so I wouldn't count on that.

-greg