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Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Donkc on October 14, 2019, 05:50:23 pm

Title: Isolator Needed or Specs
Post by: Donkc on October 14, 2019, 05:50:23 pm
I need a battery Isolator for a 1984 38Ft with a Cat 3208 Or the specs required and I can find one on line.
don@doncrawford.net  480-710-3606
Title: Re: Isolator Needed or Specs
Post by: wolfe10 on October 14, 2019, 06:14:17 pm
Don,

Welcome to the ForeForum.

Several options:

1. Go back with any diode-based isolator that meets the amp rating of your alternator. Not hard to find.
2.  Install a marine ON-OFF switch with alternator and chassis battery lead to one terminal and house battery lead to the other.
3. One of the new-generation, no voltage loss $$ isolators.
Title: Re: Isolator Needed or Specs
Post by: Pierce & Gaylie Stewart on October 14, 2019, 06:56:19 pm
Coaches are moving away from traditional isolators today. If you choose an ON-OFF switch, make sure it will carry the current. 350 amp cont. switches here with options. We always used a three position but the four position may be used also: Amazon.com : Blue Sea Systems e-Series On/Off Battery Switch : Boating... (https://www.amazon.com/Blue-Sea-Systems-Battery-Switch/dp/B000MMC914/ref=sr_1_6?dchild=1&gclid=Cj0KCQjwuZDtBRDvARIsAPXFx3A0EhGWeoXEWGpwg4nEHyHxc4MPya0yM0bArkJmPFOMmPDaCdkHcFsaAkXtEALw_wcB&hvadid=241918996496&hvdev=c&hvlocphy=9032587&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=12742629650990028347&hvtargid=kwd-11830643578&hydadcr=24634_10399774&keywords=marine%2Bon%2Boff%2Bswitch&qid=1571092827&sr=8-6&th=1)

With a switch, you may create a damaging voltage spike if you turn the switch with the engine running. See the instructions on the face of the switch.

Pierce
Title: Re: Isolator Needed or Specs
Post by: Roger & Susan in Home2 on October 14, 2019, 07:08:01 pm
A Victron zero voltage loss 200 amp isolator is $120.  About the same price as a diode isolator.
Victron Argofet Battery Isolator (https://baymarinesupply.com/electrical/isolators-29/argo-fet-battery-isolator.html)

A smart Sterling ProSplit R Zero Voltage Drop Battery Isolator for 180 amps is $190.
Sterling ProSplit-R – Zero Voltage Drop Battery Isolator (https://baymarinesupply.com/electrical/isolators-29/sterling-prosplit-r-zero-voltage-drop-battery-isolator.html)

Title: Re: Isolator Needed or Specs
Post by: Caflashbob on October 14, 2019, 07:22:57 pm
As far as I know all the new coaches come with an battery auto combiner.  Blue sea makes a 500 amp unit. 

http://assets.bluesea.com/files/resources/instructions/990180180.pdf
Title: Re: Isolator Needed or Specs
Post by: Pierce & Gaylie Stewart on October 14, 2019, 07:52:50 pm
I linked to the wrong switch. No damage will occur if using this switch. I should have linked to the 4 position switch. This one has the possibility of damage as stated on the front. Amazon.com : Blue Sea 9001E E-Series Battery Switch : Boating Battery... (https://www.amazon.com/Blue-Sea-Systems-Battery-Switch/dp/B000K2MCR2/ref=sr_1_6?dchild=1&gclid=Cj0KCQjwuZDtBRDvARIsAPXFx3A0EhGWeoXEWGpwg4nEHyHxc4MPya0yM0bArkJmPFOMmPDaCdkHcFsaAkXtEALw_wcB&hvadid=241918996496&hvdev=c&hvlocphy=9032587&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=12742629650990028347&hvtargid=kwd-11830643578&hydadcr=24634_10399774&keywords=marine%2Bon%2Boff%2Bswitch&qid=1571092827&sr=8-6&th=1)

Pierce
Title: Re: Isolator Needed or Specs
Post by: Michelle on October 14, 2019, 08:26:34 pm
Topic moved here as it seems more appropriate to technical discussion than classified ad.
Title: Re: Isolator Needed or Specs
Post by: MarkC on October 14, 2019, 09:14:28 pm
Curious, If I understand this correctly and use one of the manual switches instead of a diode isolator, does that mean while driving, it should be switched to "Both" to charge all batteries and when dry camping, it should be switched manually to the coach battery only to prevent discharging both the engine and coach batteries ?
Title: Re: Isolator Needed or Specs
Post by: wolfe10 on October 14, 2019, 09:24:15 pm
Curious, If I understand this correctly and use one of the manual switches instead of a diode isolator, does that mean while driving, it should be switched to "Both" to charge all batteries and when dry camping, it should be switched manually to the coach battery only to prevent discharging both the engine and coach batteries ?

As I posted above and Pierce correctly posted a caution about another style marine switch:

Do NOT use a 1-both-2-off switch unless you REALLY KNOW WHAT YOU ARE DOING.  Incorrectly used, you can do damage.

A simple marine ON-OFF switch with alternator output (from B+) and chassis battery to one lug and house battery to the other is an idiot-proof solution.

Here is one: e-Series On Off Battery Switch - Blue Sea Systems (http://www.bluesea.com/products/9003e/e-Series_On_Off_Battery_Switch)
Title: Re: Isolator Needed or Specs
Post by: MarkC on October 14, 2019, 09:34:22 pm
As I posted above and Pierce correctly posted a caution about another style marine switch:

Do NOT use a 1-both-2-off switch unless you REALLY KNOW WHAT YOU ARE DOING.  Incorrectly used, you can do damage.

A simple marine ON-OFF switch with alternator output (from B+) and chassis battery to one lug and house battery to the other is an idiot-proof solution.

Here is one: e-Series On Off Battery Switch - Blue Sea Systems (http://www.bluesea.com/products/9003e/e-Series_On_Off_Battery_Switch)


Thank you Brett, maybe I'm over complicating it.  If using the above On/Off switch wired as you state, does that mean the chassis battery then will always be charged when the engine is running, and the coach battery only when in the ON position ?
Thanks again for your help, don't mean to be a pain.
Title: Re: Isolator Needed or Specs
Post by: wolfe10 on October 14, 2019, 09:35:31 pm

Thank you Brett, maybe I'm over complicating it.  If using the above On/Off switch wired as you state, does that mean the chassis battery then will always be charged when the engine is running, and the coach battery only when in the ON position ?
Thanks again for your help, don't mean to be a pain.

CORRECT.  Chassis battery always charged-- hard wired to B+ terminal of alternator.

House battery only charged when switch ON.

Not only simple, but allows two other advantages:

A HD battery combine (1200 amp starter rating)

If plugged into a CG last night and planning for one tonight, you are not spending diesel to work the alternator harder to OVER-charge the house battery.  Said another way 14 VDC into an already fully charged house battery all day is not good for it.
Title: Re: Isolator Needed or Specs
Post by: MarkC on October 14, 2019, 09:42:00 pm
GOT IT ! :) , Thanks for your patience.  Also, by always having power to the chassis battery, does that also mean that you could switch the coach battery ON under power without worry of a power surge .......hence be Idiot (or Mark) Proof? 
Title: Re: Isolator Needed or Specs
Post by: wolfe10 on October 14, 2019, 09:50:26 pm
If you are talking about turning on the salesman switch by the door (which isolates most house circuits from the house battery when off), not sure it would make any difference one way or the other if the new isolator was on or off.
Title: Re: Isolator Needed or Specs
Post by: MarkC on October 14, 2019, 09:52:47 pm
If you are talking about turning on the salesman switch by the door (which isolates most house circuits from the house battery when off), not sure it would make any difference one way or the other if the new isolator was on or off.

Thanks again, I learn something everyday from this Forum!
Title: Re: Isolator Needed or Specs
Post by: Realmccoy on October 16, 2019, 08:25:39 am
Two more question for the experts: First, if you have a good size solar (900 watts) and you are running (driving) mostly during daytime, would this switch would be an effective way to keep chassis battery bank well charged without two systems trying to charge the house batteries? Second, does this affect the boost switch setting that combines house and chassis for helping to start coach in difficult situations?

My battery isolator is probably original, so my understanding is it could be at the end of its life cycle.
Title: Re: Isolator Needed or Specs
Post by: wolfe10 on October 16, 2019, 09:14:15 am
Two more question for the experts: First, if you have a good size solar (900 watts) and you are running (driving) mostly during daytime, would this switch would be an effective way to keep chassis battery bank well charged without two systems trying to charge the house batteries? YES.  WITH SWITCH OFF, WHILE DRIVING ALTERNATOR WOULD CHARGE CHASSIS BATTERY ONLY.  SOLAR WOULD CHARGE HOUSE BANK ONLY. THIS ASSUMES THAT THE SOLAR IS HOOKED ONLY TO THE HOUSE BANK WHICH IS THE "NORMAL" WAY TO WIRE IT. TURNING ON THE BOOST SWITCH OR ISOLATOR SWITCH ON WOULD HAVE BOTH SYSTEMS CHARGING BOTH BANKS.


Second, does this affect the boost switch setting that combines house and chassis for helping to start coach in difficult situations? BOOST SWITCH WOULD WORK AS BEFORE.  BUT THE MANUAL ISOLATOR SWITCH COULD SERVE AS A REDUNDANT COMBINER. SO WITH MANUAL ISOLATOR SWITCH ON, CHASSIS AND HOUSE BANKS ARE COMBINED.

My battery isolator is probably original, so my understanding is it could be at the end of its life cycle.
Title: Re: Isolator Needed or Specs
Post by: Realmccoy on October 16, 2019, 02:11:09 pm
Thank you. My solar only charges house batteries, my Trik-L charger provides charge for chassis bats while parked. That has worked well for the past three years.