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Topic: Opinions on Battery Isolators  (Read 981 times) previous topic - next topic

Opinions on Battery Isolators

I would appreciate opinions on going with a smart battery isolator as opposed to a typical diode isolator.
Thanks
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Opinions on Battery Isolators

Reply #1 –
Some of your choices (there are probably more):

1.  Diode based isolator  (Argo Diode Battery Isolators - Victron Energy

2.  FET isolator  (Argo FET Battery Isolators - Victron Energy)

3.  Combiner  (Cyrix Battery Combiners - Victron Energy)

4.  Smart Combiner  (Amazon.com : Sterling Power USA Pro Split R - Alternator 0.0V Drop Splitting...)

5.  Manual Switch  (Amazon.com : Solenoid ML 12V RBS : Boating Battery Switches : Sports & Outdoors)

Links are examples of the "type" only - not necessarily a recommendation.  Everybody has their preference.  Do your own research using the "Search" tool on this Forum, and online at vendor sites.

 Keep in mind, when combining battery banks, that different battery types sometimes require different charging profiles.

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Opinions on Battery Isolators

Reply #2 –
Excellent choices.

Add one more-- the really KISS theory one: e-Series On Off Battery Switch - Blue Sea Systems

Continuous rating: 350 AMPS
Cranking amp rating: 1200 AMPS

Alternator B+ and chassis battery cable to one lug, house battery cable to the other.

Switch off= alternator charges only chassis battery

Switch on= both banks charged AND also serves to charge chassis battery from shore power when converter or inverter/charger is charging.

Yes, requires one to turn switch on/off.  Easy to locate at foot of bed so it can be switched from inside the coach.

Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Opinions on Battery Isolators

Reply #3 –
Quote from: Res777 –
I would appreciate opinions on going with a smart battery isolator as opposed to a typical diode isolator.
Thanks
I switched to a Sterling solid state isolator. It is marine rated for water intrusion protection (IP66 waterproof) and .09 voltage loss to the battery banks. And it has diagnostic led's on it to show you at a glance if there is battery feedback isolation or over/under voltage.
Sterling USA
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Opinions on Battery Isolators

Reply #4 –
I switched to a Sterling Pro SplitR when I had 2 house battery banks,  it is a very good choice for AGM or GEL batteries. Smart functions improve battery charging while driving.

A discount may be available at Bay Marine Supply for these and for any Victron equipment.  Use ffmember in the discount code place. Sterling ProSplit-R – Zero Voltage Drop Battery Isolator

Automatic or manual combiners can help balance voltage levels between house and start batteries if they are the same battery types.

If you have Lithium house batteries and AGM start batteries then a battery to battery charger uses some output from the alternator and a smart charging profile for the Lithium batteries and lets the alternator to charge the start batteries as well while driving.

You need to have some means for charging the start batteries while parked, dry camping or plugged in.  Trickle chargers or combiners will help with that.  If you have solar it can be configured to charge both.  For those times when you are plugged in you can add a small smart charger that will charge both the house and the start batteries.  They use less power to keep the house batteries charged than using the big inverter/charger and got to a very low power standby mode when charging is not needed. Sterling ProCharge Ultra 30 Amp Boat Battery Charger

Lots of choices, lots of opinions.  The best solution is what fits your needs and use.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Opinions on Battery Isolators

Reply #5 –
Quote from: Roger & Susan in Home2 –
I switched to a Sterling Pro SplitR when I had 2 house battery banks,  it is a very good choice for AGM or GEL batteries. Smart functions improve battery charging while driving.

A discount may be available at Bay Marine Supply for these and for any Victron equipment.  Use ffmember in the discount code place.
Sterling ProSplit-R – Zero Voltage Drop Battery Isolator

Automatic or manual combiners can help balance voltage levels between house and start batteries if they are the same battery types.

If you have Lithium house batteries and AGM start batteries then a battery to battery charger uses some output from the alternator and a smart charging profile for the Lithium batteries and lets the alternator to charge the start batteries as well while driving.

You need to have some means for charging the start batteries while parked, dry camping or plugged in.  Trickle chargers or combiners will help with that.  If you have solar it can be configured to charge both.  For those times when you are plugged in you can add a small smart charger that will charge both the house and the start batteries.  They use less power to keep the house batteries charged than using the big inverter/charger and got to a very low power standby mode when charging is not needed. Sterling ProCharge Ultra 30 Amp Boat Battery Charger

Lots of choices, lots of opinions.  The best solution is what fits your needs and use.

Hi Roger,
This is my first MH so if I ask an obvious stupid question you'll know why. 😂
So with that said. How hard is the Pro SplitR to install? It looks like it takes some additional wiring as opposed to the 3 post diode splitter.
Thanks,
Robert
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Opinions on Battery Isolators

Reply #6 –
Res777, If you follow the link that I posted. There is a further link to the instruction and installation manual. I scratched my head a few times as I was also changing from the factory Leece-Neville 4 wire alternator to the more common Delco-Remy. But they talk about all this in that PDF file.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Opinions on Battery Isolators

Reply #7 –
The Sterling ProSplitR is easy to connect.  Alternator to the alternator post, start batteries to the start battery post and the house batteries to the Aux1 post.  If there is a Aux 2 post and you only have one set of house batteries then a cable goes from there to the house batteries as well.  These are likely the same cables you have now that go to either side of the boost solenoid.  Foretravel didn't over size these at all.  Doesn't hurt to use bigger cables.

There is a small start battery post, this is a sense wire from the start battery, same as goes to most alternators.
There is an ignition post as well, it gets connected to an ignition powered wire, same as the excite wire for the LN alternator.

It is not hard, but even though it is from an English country, Sterling has a odd way of describing things
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Opinions on Battery Isolators

Reply #8 –
Quote from: Roger & Susan in Home2 –
The Sterling ProSplitR is easy to connect.  Alternator to the alternator post, start batteries to the start battery post and the house batteries to the Aux1 post.  If there is a Aux 2 post and you only have one set of house batteries then a cable goes from there to the house batteries as well.  These are likely the same cables you have now that go to either side of the boost solenoid.  Foretravel didn't over size these at all.  Doesn't hurt to use bigger cables.

There is a small start battery post, this is a sense wire from the start battery, same as goes to most alternators.
There is an ignition post as well, it gets connected to an ignition powered wire, same as the excite wire for the LN alternator.
It is not hard, but even though it is from an English country, Sterling has a odd way of describing things

Thanks for the info. One more question. If I change to the ProSplitR. Will that effect the operation of the boost switch?
Thanks
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Opinions on Battery Isolators

Reply #9 –
No change to the function of the boost switch.

When you run the engine the start batteries get priority first until they are mostly recharged and the the house batteries get most of the output from the alternator. The ProSplitR checks the start battery voltage periodically and if it n needs some charge priority switches back to the start.  You get faster charging of the house batteries while driving.

This is a good choice for replacing the old diode isolator.  There are several other ways to do the same thing, all have some thumbs up and some thumbs down.

If you have a Leece Neville alternator its output voltage Was increased at the factory to compensate for the voltage loss in the diode isolator.  You can adjust the voltage output down so the with the engine set to run on a middle idle speed the voltage measured at the start battery should be about 13.8 volts.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN