70 AMP BATTERY ISOLATOR

[Chuck Craven]

Chuck
If you come up with something like that I would be very interested in it too.

I am thinking of two high-speed transformers connected primary to primary. Using a chopper circuit for the 12v drive side, witch would be the output side of the first transformer. I have never tried to run switching transformers back to back. That may be the showstopper. But to wind a 1:1.5 transformer for switching speeds may be a little tedious but that can also be done. Winding a transformer on a torrid core may be the easiest and still have some efficiency. I am still in the humming stage of the thought processes.
Chuck.

[Gerdo]

With a battery isolater can I run a #10 wire from it to the trailer battery?

[Leon]

Yes

[Gerdo]

Do you spec your isolater by the size the size of your alternator or the wire or what? 70 amp iso for a 70 amp alt? 30 amp iso for #10 30 amp wire?

If I have a 110 amp alt and #10 awg wire feeding the TD battery, what size iso should/can I use?

[Chuck Craven]

Do you spec your isolater by the size the size of your alternator or the wire or what? 70 amp iso for a 70 amp alt? 30 amp iso for #10 30 amp wire?

If I have a 110 amp alt and #10 awg wire feeding the TD battery, what size iso should/can I use?

You want an Isolator for the size of the alternator you have.
110 amps, alternator needs a 110 amps or larger isolator.
Also the batteries need to be about the same size. Amp/hr ratting.
You can use a deep discharge battery with the normal car/truck starting battery.
Just remember if you use the deep discharge battery for starting it will shorten its life.
Wire size needs to be #2 awg for 4 feet or less.
Chuck

[bdosborn]

Gerdo,
I've played with those type of isolators and don't like them much. They use a diode to separate the batteries and introduce a 0.7V drop on the line. So your charging voltage goes from about 14.3V to 13.6V (and even less by the time it makes it to your trailer battery). Also, you need to install them right after the alternator and I hate cutting factory wiring. But, if you want to use one you would pick one rated for your alternator output, use wire rated for the alternator output into the isolator, use alternator output sized wire from the isolator to the tow vehicle and #10 or #8 to the trailer (depending on if you have a long vehicle and more than one battery). My truck has a 40A fuse to the trailer with the factory charging circuit, which would be a #8 wire. I've never checked the wire to see if its really a #8 .

I just unplug the trailer when we stop for longer than 4 hours or so, leaving it plugged in while getting fuel or lunch hasn't been a problem. I also try and start the truck before I plug the trailer back in.
Bruce
P.S. I refuse to read any of the previous posts having anything to do with you-know-who so forgive me if I've repeated anything.

[Leon]

[bledsoe3]

P.S. I refuse to read any of the previous posts having anything to do with you-know-who so forgive me if I've repeated anything.

Didn't we have this conversation at the IRG?

[bdosborn]

Didn't we have this conversation at the IRG?

Jim,
Yup. I still get steamed up reading those posts so I just don't do it. I was a lttle nervous just to see a reply to this post.
Bruce

[Chuck Craven]

bledsoe3 or bdosborn

I was not at IRG! Can you PM me!
Give me a heads up. Before I post my new electrical panel. I don’t want to start a brawl!
I ware combat boots, don’t want to trample on those with sandals!



Chuck

[bledsoe3]

bledsoe3 or bdosborn

I was not at IRG! Can you PM me!
Give me a heads up. Before I post my new electrical panel. I don’t want to start a brawl!
I ware combat boots, don’t want to trample on those with sandals!



Chuck

Chuck, I sent you a PM.
And by all means, please do post your electrical panel.

P.S. Don't forget the pictures for Jack. He really luv's them!

[madjack]

Chuck, we did away with our electrical brawler so post away...I for one would like to see what you have done...electrically that is
madjack

[Chuck Craven]

Ok Madjack!
I have to redo one picture and work on getting my schematic into a Jpeg format.
Should have it ready some time around Sep. 11
Chuck

[Gerdo]

Would you sugest a selinoid instead of an iso? This would give the TD battery constant voltage but only when the TV is running. Your TV battery gets constant voltage and it doesn't hurt it so it shouldn't hurt the TD battery either, Right?

[bdosborn]

That's what I'm going to do if I ever get tired of unplugging the trailer. Just make sure the solenoid is continuously rated. (Starter solenoids are not).
Bruce