I have searched, but could not find on the tech forum recomendations for a new replacement for my 12vdc isolator.
Help?
It needs be rated for or exceed the amperage of your alternator.
Like Chuck recommends, meet or exceed your alternator. Look on alternator for model number and then go online for the output. Any doubts, call the distributor with the part number. Check with RV sources like PPL ( Battery Isolators by Noco - PPL Motor Homes (http://www.pplmotorhomes.com/parts/rv-converters/battery-isolator-noco.htm)) for a new one.
When you replace, disconnect all batteries, and make SURE all cables are marked. The factory marking may have faded. Mine was replaced and the wrong connections made a year before I bought it and several things did not work. Caused me a lot of head scratching until I figured it out. I used a Brother label machine to mark each one. Makes it a no-brainer to replace.
Pierce
You probably have a 160 or 190 amp alternator but you need to check that. You can look for a 300 amp isolator and that should cover it even if you upgrade later on....I am planning on uprating mine sooner or later.
I always call FT Parts first. Even if you don't buy from them, you know you're looking for the right thing.
So why are there 4 terminals on top of the Noco isolator while the one in my coach has only 3?
Some are designed with two inputs and two outputs. You jumper an input.
It might be time to remind people that Foretravel has transitioned to an electronic isolator on newer coaches. I think Brett brought it up. A bit pricier, it gets rid of the half volt drop as it doesn't use diode.
Actually, this Brett likes MANUAL.
I use a marine ON-OFF switch rated at 360 amps continuous. Inexpensive and bomb-proof.
Alternator output and chassis battery are on one lug of the switch. House battery on the other log.
Switch off, alternator charges chassis battery (they are hard wired to the same lug).
Switch on, alternator charges BOTH batteries.
WHY:
No voltage drop across a diode-based isolator (turned into HEAT).
No need to subject a fully charged house battery (plugged in overnight and will be plugged in tonight-- not dry camping) to OVER-charging all day. Said another way, no need to burn diesel into power the alternator to subject the house bank to 14.0 or so all day long.
No potential failure of a diode-based isolator OR a solenoid/relay-based isolator.
What is the name of the Foretravel electronic isolator? A year ago, at the IH-45 announcement, we saw that IH-45 had a big diode style isolator with large curved cooling fins, so that build still used the old style.
I did hear that several years ago Foretravel was selling a marine voltage controlled relay to combine house & start battery banks (to replace Trik L Start type combiner). Anyone know the name of this combiner?
I was gratified to read your view on a manual marine-type battery switch. I've used them on boats for 40 years and have been considering something like that myself.
Where did you mount the switch, Brett?
Craig
Craig,
Like you, I had used a simple Perko switch on our sailboats for decades. I mounted it on the "kick panel" under the forward edge of the bed with the switch easily accessible at the forward edge of the bed.
I also brought all wiring and relays mounted behind the driver's side mud flap into that area. Labeled all wires, relocated the panel they were mounted on to the "electric compartment" between engine room forward wall and the wall the 120 VAC breaker box is mounted on. All wires were long enough that no splicing was required. A MUCH better location for electrical components!
Brett... perfect. Gets all the connections up and out of the worst of the spray in wet weather, too. Thanks. :)
Craig