Battery Isolators,Separators, and Switches?

[daveb]

On 50 style models most of the separators were installed under the bench seat near the left rear of the seat. Usually if solar was installed at a later date there is a strong possibility they ripped out the isolator (if it had one) and re built the system like the more modern vans. This would make sense if you have a solar boost controller.

With the 7622 there is no reason to add a switch to jump start the chassis system other than ease of access. The separator has full control built into it. You can set it to:

A)Normal automatic operation which monitors and connects or opens depending on the state of charge of each battery bank or if the separator sees a charge.

B)Full isolation (always open) which keeps the batteries from ever connecting.

C)Full connection (always closed) used to jump start etc.

You can also lock it open with a zip tie or small lock so others can't accidentally operate it. The problem is seeing it. On the 50 model SMB usually mounts it in an out of the way spot. I added the remote switch so I have full control at an easy to see spot, something you might want to keep out of the hands of kids. I also wired mine to automatically open during vehicle starting. After about 15 seconds it closes and returns to normal operation. That way I'll know if I'm having starting battery issues. Jumping is rare so when needed you can use the jump mode at the push of a button (on the remote) or turn of a knob (on the separator itself).
Kind of just depends on your SMB model and/or where they put the separator.

So, do you have a diesel or gasser?

[DosMars]

Update and a few more questions...
So it turns out my alternator was bad along with a bad second starter battery (this is my first diesel, didn't realize it was located remotely next to the house battery). Things are running smoothly now, but they were unfamiliar with the Blue Sea unit & didn't feel comfortable trying to figure things out.

Question:
I'm located in Long Beach California. Can anyone from around here recommend a shop that is familiar with this installation? I'll see if google can find me a van-conversion shop but I'd prefer a recommendation if it's reasonably close by.

You mentioned the Blue Sea has a switch or remote that you can use to toggle between the starter battery and the house or use both in the event you have to jump start the van. I don't see any switch on the unit? What am I looking for, I wasn't shown a remote when I was shown the unit?

The AAA guy had a hard time helping me jump start the van so I could get to the shop. It took his booster along with the truck running before I was getting enough juice to turn over. Once I get the Blue Sea installed and figured out, will the house battery alone be able to handle the job, or will it take both systems running in tandem to get me started if I have to jump start myself ?

Thanks again for taking the time to walk me through this system. Getting more comfortable with things but expect more questions to come!

-Mark...

[daveb]

Depends on what unit you have. Blue Sea makes several models including isolators. The 7622 I have is actually called ML-ACR Automatic Charging Relay with Manual Control - 12V DC 500A
The yellow knob is the control and the red switch is the optional remote.



For safe and correct jump starting you need to use heavy enough gauge wire connecting the battery systems.
Face it, if you have a dead and/or shorted starting battery you might have a hard time getting the vehicle started unless you take it out of the loop. Low voltage is rough on the FICM also. You can allow the house system to equalize a dead battery that is not bad by connecting the battery systems for several minutes and then attempt to start the vehicle. If the bad battery is shorted it will just kill the others and even if you do get enough to start the vehicle, it's very possible the bad battery will boil, get hot and off gas as the alternator charges. This is bad also. I lost my first alternator due to this. I've never seen a battery explode during the engine being ran, but it's possible.

[flyfisher]

Wow! this just makes my old head hurt! I'm getting ready to have a 135 watt solar panel installed on The Van, and wandered into this thread thinking I might find some answers to my questions...

Why can't it be easy? I've never had any problems with two days of camping and having my house battery run the reefer, and maybe a few lights. After that I've taken a 1/2 hour drive to charge up the battery. I want to get the solar panel installed to keep the reefer running, and maybe not have to start The Van up to top off the battery.

I have a 2005 SMB and a Lifeline 4D AGM battery for the house battery, and The Van is always plugged into shore power when I'm not using it.

Here are my questions:

The Van alternator charges both House and Van batteries when I'm driving, so they should always be topped up when I get to my campsite?

The "separator" keeps me from discharging my Van battery when I'm camped, so even if I run the House battery down, I should have power to start The Van?

Should I have to add anything to the system to make what SMB installed when I bought The Van better?

What do I need to know about the Solar system to tell the installers? The folks who are going to install it work on RV's and have a good track record for installing solar. (I'm leaning towards a Samlex 135 watt kit that includes everything needed to get the juice to the battery, I hope).

Auto electronics have always scared me, I don't have any problem wiring my house, Hell, I've even mastered 3 way switches, but somehow the electrical stuff in my SMB is way off the edge of my understanding, so any help would be appreciated.

I just want The Van to start after it's been sitting in a nice campsite way the Hell and gone off the grid for a couple days.

thanks...

Tom

[daveb]

The Van alternator charges both House and Van batteries when I'm driving, so they should always be topped up when I get to my campsite?

Almost. Alternators generally get you to about 95%. Not an issue though because most of the float voltage drains off quickly. That 5% is more important during storage.

The "separator" keeps me from discharging my Van battery when I'm camped, so even if I run the House battery down, I should have power to start The Van?

Provided the separator is working correctly yes. There are different types of battery separator though. Also if you have a radio that pulls off the starting battery you still might have an issue if it's left on all night. Same as leaving your headlights on.

Should I have to add anything to the system to make what SMB installed when I bought The Van better?

Solar and a good battery monitor gauge. I replaced my Surepower separator with a blue sea which helped me.

What do I need to know about the Solar system to tell the installers? The folks who are going to install it work on RV's and have a good track record for installing solar. (I'm leaning towards a Samlex 135 watt kit that includes everything needed to get the juice to the battery, I hope).

A good correctly rated controller (MPPT type). Always plan for the future. Try to find panels that are somewhat universal in size. You want a panel that will still be around when one fails. A good mounting system. Proper entry of cables into the van, you don't want water leaks. If they don't understand SMB tops be very careful. Just letting them punch holes might be a disaster. Size the panels to the house battery but just remember when it's foggy or overcast more is better. Don't expect to run heavy loads off your solar...there isn't enough roof to add that many panels. 135 watts is generally enough to supply a charge while also adding a bit of charge.



Auto electronics have always scared me, I don't have any problem wiring my house, Hell, I've even mastered 3 way switches, but somehow the electrical stuff in my SMB is way off the edge of my understanding, so any help would be appreciated.

There is some info in this sections FAQ's

I just want The Van to start after it's been sitting in a nice campsite way the Hell and gone off the grid for a couple days.

It is a nice backup to have Tom, good luck.

I probably missed something. I'm sure others will chime in

[flyfisher]

Thanks for the reply Dave, this is a great help.

Tom

[daveb]

Originally Posted by flyfisher

Thanks for the reply Dave, this is a great help.

Tom

I'm sure you've read Greg's post:

Originally Posted by Scalf77

I would think key attributes to look for would be:
- make sure that your Voc and Isc ratings of the controller match that of your panels.
This is where the in series or parallel becomes important. It would also drive if you stayed with MPPT or went with PWM. Your panel Vmp is high enough that you could get some benefit from MPPT especially in cooler weather. If you keep them in series you have to go MPPT.
- at least a 3 stage charger (4 if you include equalization)
- different set points for absorption, float, and equalization. (can you match your battery type)
Programmable option would be even better

Additional items (especially if you are picky about the voltage levels for charging
- Battery sense wires, these are no load wires that measure the actual battery voltage, it has improved accuracy
-Temperature sensor, this will compensate the voltage levels based on temperature of battery.

As far as monitoring functions, it really depends on how much of a data junky you are. I would think at a minimal that I would like to be able to see PV voltage and current, some units will keep track of total power generated.

I would put myself in the category of having a separate battery monitor.

-greg

Maybe print this Tom and take it with you. If they don't understand what Greg is talking about they might just be generic as far as installation goes. Not saying they can't do it right.

Dave

[Chance]

Originally Posted by Scalf77

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What do I use now? I use a variation of the second solution, instead of using a switch to turn on the solenoid I tap into the “Run Circuit”.

I am currently using the Trombetta 114-1211-020 Solenoid that came off of my SurePower 1315. It is rated at 225 Amps continuous duty, 1.5 amps closed, silver alloy contacts, 50,000 lifetime cycles. If purchased new it would go for $42.00. The primary mode that is used every day is that the Solenoid is tied the “Run Circuit” on the key switch, you could also tap off of the trailer light relay. In either case if the van is running the solenoid is closed and both batteries are being charged. The small relay let’s me use a switch to turn it on when not in “Run” mode. I also have a switch on the ground connection of the coil, this just disables the solenoid. I also have a Blue Sea 6007 switch, this is my back up switch. If the solenoid goes bad I move the Blue Sea switch to bypass the solenoid. I did have my SurePower develop a problem while on Vacation; this could have made dealing with that issue a lot easier. So I have less than $100.00 dollars invested in a pretty robust solution. I may move to a Magnetic Latch Relay at some time also, but they are more difficult to wire up to the run circuit, because they only need a pulse and the polarity or input changes.

.....cut.......

Very nice and informative post.

I like your simple solution above. A solenoid tied to the run circuit seems to avoid the main problem of forgetting to disconnect the battery, or to accidentally bump the switch to on position. The thing that's hard for me to accept of myself is that I could forget to manually disconnect the house battery any more than driving off with the parking brake on, or driving away from a camp site while still connected. I don't know at what point we should rely on automation to avoid having to remember things when it complicates other factors. Regardless, I like your system knowing that I too would forget at some point.

I'm curious about the use of the Blue Sea switch to bypass the solenoid relay in case of failure. Could you not do the same with an on/off switch across the solenoid? That way the normal power wouldn't have to go across an additional contact. I'm assuming such a switch is made, but are there any downsides to that versus what you show above? Cost-wise I'm sure it wouldn't make much difference. Just not sure if I'm overlooking something.


Also, while on this subject, have you looked at multiple solenoids and/or manual switches to allow charging multiple house batteries one at a time? Is there an automated device to do this? Or a simple way to limit current when too many batteries are in parallel? If I upgrade my present van or build another homebuilt (not that I'm seriously thinking about this) I'd include at least two house batteries, and I'd prefer to charge one at a time over a longer period to keep from potentially overheating the alternator. My preference would be a second independent alternator system but that's a different topic entirely -- and an option not available on most vans anyway.

[daveb]

Originally Posted by Chance

Very nice and informative post.

I like your simple solution above. A solenoid tied to the run circuit seems to avoid the main problem of forgetting to disconnect the battery, or to accidentally bump the switch to on position. The thing that's hard for me to accept of myself is that I could forget to manually disconnect the house battery any more than driving off with the parking brake on, or driving away from a camp site while still connected. I don't know at what point we should rely on automation to avoid having to remember things when it complicates other factors. Regardless, I like your system knowing that I too would forget at some point.

I'm curious about the use of the Blue Sea switch to bypass the solenoid relay in case of failure. Could you not do the same with an on/off switch across the solenoid? That way the normal power wouldn't have to go across an additional contact. I'm assuming such a switch is made, but are there any downsides to that versus what you show above? Cost-wise I'm sure it wouldn't make much difference. Just not sure if I'm overlooking something.


Also, while on this subject, have you looked at multiple solenoids and/or manual switches to allow charging multiple house batteries one at a time? Is there an automated device to do this? Or a simple way to limit current when too many batteries are in parallel? If I upgrade my present van or build another homebuilt (not that I'm seriously thinking about this) I'd include at least two house batteries, and I'd prefer to charge one at a time over a longer period to keep from potentially overheating the alternator. My preference would be a second independent alternator system but that's a different topic entirely -- and an option not available on most vans anyway.

You nailed the reason that SMB suggests not to have a remote switch. Forget how it's set or the fact that little kids like to push buttons. One nice thing about the blue sea remote is that it's lighted so one glance and you know what setting it's on. It doesn’t help if you drive 300 miles and pull into camp with low batteries.

With the separator itself, the unit still has the same full manual controls as the remote. So you can do what you want to with that separator and in most cases you would be setting it to Jump (manually close it) in an emergency or lock it out such as if you are working on that circuit and you don't want it to close. In my case the solar is hooked to the house battery side so with the separator open I still charge the house system. If the shop is working on the starting vans electrical system and I don't want the solar to cause the separator to close, it can be pad locked in the off position. I do this when the van goes into the shop (although I use the remote switch).


As far as charging and being able to isolate two or more batteries, there are some good reasons to be able to do that. One is if a battery failed, the separator would open and protect it from the other. You could also pick which battery or all the batteries to charge. It would also give you the opportunity to run off one or more batteries if you choose. But there is the KISS factor to throw in the mix not to mention oops, I forgot to open this or close that. Lastly there would be the overall cost. The more lugs, spades, and wiring there is, the more that something could be compromised. But the cool factor would be huge...3 or four remotes all lit up and all those switches would be impressive. Just think what a little kid could do with those.

[Scalf77]

The reason I use the blue sea switch, is that it takes a possible failing component out of the equation. If I rely on a separate switch to enable the solenoid as a backup, it does not help if the solenoid itself is failing, (Dirty Contacts, failed return spring). By using the hard wired circuit, I can get around the failing solenoid. It may be somewhat inconvenient, but if you are in the middle of a trip when it happens, it would be worth it

Switch 1: Solenoid ( Normal everyday position)
Switch 2: Hard Wired ( for debug or redundancy)
Off: Full disconnect (great if you taking van into shop) or Debug



The same switch could be used in a two separate house battery system. It would be manual, but still pretty easy to deal with. I expect there may be a automated way that exist, if not it would be in the realm of possibility.

-greg