Battery Isolators,Separators, and Switches? - Page 3

shenrie · 12-03-2012, 10:51 AM

perfect! again, thank you for taking the time to write this up and make all the illistrations for everyone. super great info for the noobs like me!!

Spoolin · 07-10-2013, 02:52 AM

I just want to say thank you for this write up. I'm about to start tackling my house electrical and this has answered all my questions about what I had been wanting to do. A friend actually gave me a silicone based Isolater but think I'm gonna go with the Perfect switch. Not sure yet but this has put me on the right track! Thanks for the wonderful write up!!!

E350 · 07-10-2013, 08:47 AM

Scalf77: As a completely different alternative, with the 7.3L we have two positions for alternators. And our alternators are not controlled by the PCM. So can't we have two completely separate charging systems? One which independently charges the starting batteries. And the second which independently charges the house battery. And, thus, forget this entire topic?

What are the benefits/risks/detriments to my suggested solution?

For later engines: If an engine has positions for (i.e., room to install) two alternators, and the first alternator (the starting battery alternator) is PCM controlled, why couldn't a second alternator which is regulator controlled (e.g., internal to the alternator) be installed in the second alternator position? They would be independent of each other so why would it make a difference if the PCM did not control the second alternator?

Finally, and most importantly, thank you for the great article.

jumpshowhigh · 07-10-2013, 12:00 PM

Yes, you could have two alternators with each alternator charging its own battery or bank....that would be an ideal situation but depending on the engine, a second alternator isn't always feasible.

Quote:

Originally Posted by E350

Scalf77: As a completely different alternative, with the 7.3L we have two positions for alternators. And our alternators are not controlled by the PCM. So can't we have two completely separate charging systems? One which independently charges the starting batteries. And the second which independently charges the house battery. And, thus, forget this entire topic?

What are the benefits/risks/detriments to my suggested solution?

For later engines: If an engine has positions for (i.e., room to install) two alternators, and the first alternator (the starting battery alternator) is PCM controlled, why couldn't a second alternator which is regulator controlled (e.g., internal to the alternator) be installed in the second alternator position? They would be independent of each other so why would it make a difference if the PCM did not control the second alternator?

Finally, and most importantly, thank you for the great article.

jage · 07-15-2013, 08:23 PM

In the dual, separate alternator, what controls keep the alternator from over-charging each set of batteries?

I think I'd rather have normal dual alternator and a separator- a lot more flexible and you get the power of duals rather than running two separately.

**daveb** · 07-15-2013, 08:51 PM

I agree but I would like a better regulator.
Myself I have yet to have any issues with my heavy duty alternator. I can see issues with standard belts trying to turn big alternators but serpentine belts are fairly large. We have fleet vehicles with high amp alternator and haven't had issues but there might be a limit to size.
Guess time will tell

E350 · 07-16-2013, 08:39 AM

Quote:

Originally Posted by jage

In the dual, separate alternator, what controls keep the alternator from over-charging each set of batteries?

Correct me if I am wrong, but the same thing that prevents a single alternator from over-charging a battery -- a regulator. The alternators for the 7.3 have the regulator inside the alternator, so I believe they are stand alone units. The Ample Power alternators which Chance posted not only have their own regulator, but have temperature compensation so as to vary the charge depending on the battery's(ies') temperature (so as not to boil it over), and are "smart" in that they go from bulk charge to float charge, and they also have a remote LED monitor to display what the alternator is doing/battery charge condition.

See:

http://www.amplepower.com/products/alte ... index.html

Scalf77 · 07-16-2013, 06:06 PM

I agree if you wanted to go the way of dual alternators, that using the amplepower solution would be the way to go. It would certainly turn it into more of a true charging system. While I agree with the benefits of temperature compensation, I am not sure that it would stop boil over. Not saying it still doesn't look like a good system. It probably deserves it own thread for real discussion.

Dual alternators give you two completely isolated systems, this could be a plus or a minus, but on average I would score it a plus. It would be easier to debug at least theoretically.

Dual alternators certainly give you more power, it would really depend on your needs, I think most of us can get enough power out of one of the higher power alternators available. If you only need a max of 180 amps having 300 amps available does not really matter. I do not think just using a standard internally regulated alternator for the second alternator makes it worthwhile if you could get the power out of one.

I suspect that having one alternator being controlled by the PCM and the other by its own regulator would be just fine as long as they were truly isolated.

So while I see benefits in doing this, it appears to come at a higher cost then just using a separator. That money may be better spent on a monitoring system and/or solar.

If you never plan on plugging in or having solar, then using the amplepower solution becomes even more attractive.

-greg

BrianW · 08-09-2013, 09:07 AM

This thread is an amazing resource. Thanks to all who contributed!

Question: I have a 1998 Ford SMB 5.4 gasser with the older Sure Power isolator setup. Although I haven't had any problems with it, just to be proactive I'm thinking of replacing it with a separator. I don't have solar yet, but am hoping to add a panel or two in the future.

With that in mind, would I be better off going with the Surepower 1315 or 1314? Or are people liking the Blue Sea separators more than the Sure Powers? The Blue Sea has a higher price tag at ~$170 vs ~$100 for the Sure Power 1315-200. I would like the option of being able to use the house batteries to start the van in an emergency, but I've never had any problem with my van battery going dead.

Also, if anyone has the instructions from SMB-West about replacing the isolator with a separator, I'd love to get a copy. Calling SMB-W often can be a time-consuming came of back and forth.

Thanks!

rockbender · 08-09-2013, 10:58 AM

If going the SP route, get the 1314 to go with the solar. The reason being is that the 1314 only senses charge / connects when voltage is high on the starting battery side. Otherwise, with a 1315 that closes when it sees voltage over 13-ish from either side (I don't remember the exact number) you can have a scenario with very discharged house batteries and when the sun comes up the solar panels raise the voltage to a point on the house batteries that they connect to the van battery. Now you have your van battery and house battery trying to equalize each other and effectively discharging your starting battery.

Also, the isolator solenoid itself pulls about 1a. When you only are getting 2-8 amps (depending on sun and your solar array) the last thing you want to do is give up 1a just to power a switch.

I've got a 1315 but manually disconnect it while camping. This makes it not so much of an automated switch now! I might put a relay in that makes it connect when the engine is on to automate it a little more... or just buy a 1314/Bluesea down the road.