Cdi rectifier and charging

[rzkas]

Hi? I have a 95 120 force with a cdi rectifier and stator. My rectifier has two yellow wires and one gray wire. Which of this wire is primarly for charging or is the alternator wire.

I am working on installing a battery isolaton on my boat. One battery for starting the boat only and second for accessories. My isolator instruction says to connect the wires that comes from the isolator "a" terminal to the yellow and gray wire that comes from the rectifier but my cdi rectifier has two yellow wires and a gray wire.

I want to know where and which wire to tap/splies into and connect my isolator a terminal wire to charge my second battery and not using any power what so ever from my main starting battery.

I tried to connect the wire that comes from the isolator a terminal to the location on the engine where the main positive wire comes from. It charges my battery but my accessories are feeding on both battery. How do i found out. I took out/off the positive cable from my second battery and my accessories are still on and when i took off the power wire from the main starting battery they went off.

This tells me that because the wires that comes from the isolator a terminal is having a direct contact with the boat main positive cable at the engine terminal where the main positive wire came from .

So i think the battery isolator instruction is saying to avoid that, tap directly to the yellow and gray wire that comes from the rectifier before it get to the terminal where the main positive engine wire originate from and goes to the main starting battery.

Thanks for all your help. God bless.

 

[Robert D]

Re: Cdi rectifier and charging

There should be 2 wires coming off the stator, going to the rectifier. One of those will have a wire coming off it at the plug for the tachometer signal. You should have one wire left coming off the rectifier, and that usually goes to the battery terminal at the starter solonoid. (Via a connection at the buss bar.) This is the wire that supplies the voltage to charge with, and what they want you to redirect to the isolator. Most rectifiers are grounded by the mount to the block, however some will have an additional black wire that is a ground.

 

[fucawi]

Re: Cdi rectifier and charging

if you are talking about a 1 2 1+2 off marine switch then the function of terminal A is to turn of the alternator field current before the batteries are disconnected at off ...this only applies to large engines with car type alternators usually inboards. Do no use A . connect batteries to 1 and 2 and original battery cable to E .

personally for what you want I would have been fitting a dual charge /split charge system to charge your second battey battery when the engine runs and disconnect it when it does not . similar to that on a 4 x 4 .

 

[Robert D]

Re: Cdi rectifier and charging

I think he did describe an isolator instead of the typical 1,2,1+2,off switch. The solid state isolators work well in keeping the 2 batteries separated...and charged without having to use the typical marine switch. But it is nice to be able to have the easy option to start the engine on the 2nd battery....or both batteries.

 

[fucawi]

Re: Cdi rectifier and charging

If your isolator is one of those double diode things then bin it now ...they cause a voltage drop across the diodes of 0.7v which although small will mean your batteries do not fully charge ..old 1970s technology ..not good..get a proper VSR ( Voltage Sensitive Relay )

 

[rzkas]

Re: Cdi rectifier and charging

yeah i noticed that when my engine is running my main starting battery with the positive cable that comes from the engine is getting a better charge than my accessories battery. it get it charge from the isolator.