isolator

ricksrster

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I am wiring an isolator to a 1977 Mercury 850. Does the alt. terminal on the isolator connect to the rectified or non-rectified side of the rectifier?
 

ricksrster

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Re: isolator

this is for a Switched ( one/both/two) two battery, one motor setup.
 

Chris1956

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Mar 25, 2004
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Re: isolator

Rick, That motor's charging system is not set up for that kind of device, since:<br /><br />The charging current is small (~70 watts)<br /><br />You will get a voltage drop using the isolator, which will further reduce the charging ability<br /><br />The charging circuit is connected to the battery circuit under the cowling. You will need to run a seperate wire from the motor to your isolator.<br /><br />I recommend you use a battery combiner device instead. It has no voltage drop, does not require a battery switch or changes to your motor's wiring.
 

Boatist

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Apr 22, 2002
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Re: isolator

Rick<br />From your discription I do not think you have an asolator. Sounds more like you have a Battery Switch. If it has a one/both/two positions I think you have a simple Battery switch not an isolator.
 

ricksrster

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Re: isolator

It is an isolator plus a switch. The question I had was about the wire from the rectifier to the Alt. post on the isolator. The instructions with the isolator were unclear. I have since found out to disconnect the red wire at the rectifer and connect there. The voltage drop should not be much of a problem because my voltage is almost 16v.<br /> If I went to a combiner, I would definitely want one that isolates during charging.
 

Boatist

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Re: isolator

Rick<br />Sounds like you have it set up. I agree with 16 volts out isolator is the way to go. I have used a isolator on my boat since 1980 and never had any problems. Batteries last 6 years or more and alternator is still good. Also eliminates all the problems from turning a battery switch with the engine running, I think the number one killer of alternator diodes. I assume you used the rectified output.<br />Glad to see you got it going.
 

ricksrster

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Re: isolator

Yes, I used used the rectified side of the rectifier. When fishing, I want two use a second battery for the fish finder, lights, and other accessories.
 
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