Adding another rectifier

[hpwells1]

hello all. Just joined this forum. I have a 2004 mercury 60HP 4 stroke, ser # OT901530, mold # 60 ELPT EPI. I recently added another battery to my boat for my electronics and I was wondering if I could add another rectifier connected to the stator to charge this battery? I have seen on you tube that it was possible but they were doing this on a 25 hp Yamaha motor.
hpwells1

 

[Chris1956]

What are you trying to accomplish? if you simply want both batteries to charge, connect them via a battery switch, and set it to both. You could also just connect both batteries in parallel with cables.

If you want to isolate the batteries from each other, say one battery for starting and one for trolling, you can use a battery isolator or a battery combiner.

Another rectifier or voltage regulator is unnecessary, and gives no advantage.

 

[hpwells1]

Thanks Chris for that info.
What are you trying to accomplish? What I am trying to do is keep my electronics battery charged because I recently updated my electronics and if it gets below 10.5 volts it don't work very well. The switch may be the answer for what I am doing. So when in both will that charge both batteries? and will it also connect both for starting?.

hpwells1

 

[Chris1956]

Gee, unless you are running some powerful electronics with the engine off, 2 batteries should have lots of power for your electronics. if you run powerful electronics, set the battery switch to the odd battery on odd days and even battery on even days, when you stop the engine.

After starting the engine to go home, set the battery switch to both.

A battery combiner will do the switching for you automatically, however, you would need to wire the electronics to one battery and the engine starting cables to the other battery. No battery switch would be needed.

 

[hpwells1]

Ok,so to answer my original question , can an additional rectifier be added to my engine without damaging it?

hpwells1

 

[dingbat]

Ok,so to answer my original question , can an additional rectifier be added to my engine without damaging it?

hpwells1

The rectifier does not generate power, it simply converts the stator generated AC to usable DC power.

Unless you increase the output of the stator, adding second rectifier buys you nothing except the possibly of over loading the charging system, frying it in the process

If you want to charge both batteries you need a battery switch or a ACR.

BTW 10.5 VDC is technically a dead battery. Do that enough times and you’ll need a new battery as well.

 

[Chris1956]

I am not sure if that would damage the regulator or rectifier. It will cause you to modify the wiring, possibly leading to corrosion or other wiring issues.

I do not think a second rectifier provides any advantage however. A rectifier is simply a set of diodes that allow AC voltage and current to flow one way, converting it to DC voltage and current. You can buy a battery isolator, which is a diode that you connect between batteries. These are easy to install and weatherproof. It allows one way current flow, to charge a second battery. It causes a voltage drop of about 1 volt.

This will not damage your charging system, and has the same effect as a second rectifier.

A battery combiner is a bit better. It is a relay that connects a second battery to the charging system, when the first battery is fully charged. It has zero voltage drop.

 

[hpwells1]

Thank you both very much for answering my question. I am going to go with a battery combiner. Again, thank you.

hpwells1

 

[hpwells1]

The rectifier does not generate power, it simply converts the stator generated AC to usable DC power.

Unless you increase the output of the stator, adding second rectifier buys you nothing except the possibly of over loading the charging system, frying it in the process

If you want to charge both batteries you need a battery switch or a ACR.

BTW 10.5 VDC is technically a dead battery. Do that enough times and you’ll need a new battery as well.

What size wire do you recommend I use with a ACR

hpwells1

 

[Chris1956]

Gee, what is the charging capacity of your motor? no more than 30A. I would think, so, say 15A most on the second battery, 10AWG wire gets it, plus some extra.

 

[Thirsty Endgrain]

If your battery hits 10.5v, as stated, it's pretty much time for a new battery. Or it needs some serious attention to eek some more life out of it. If it's a lead acid battery it takes maintenance! Fully charge the battery, as much as it will accept. Then let it rest for 24 hrs. Check the voltage then, that is its resting voltage. If it's below 12.2-12.3 you will not be getting much more life. A healthy battery will rest at 12.6 and above.

After it has fully charged and rested: Open the top - with Chem resistant gloves and goggles, check the fluid level. It should be close to the top, maybe 1/2"-3/4" down, either way all of the plates need to be submerged. If the plates are exposed then your battery is already in bad shape. If low, fill with distilled water until the plates are submerged. Then charge, rest, and test again.

If it fails the above then it's new battery time.

I would not personally entertain wasting money on a Chinazon ACR that is labeled, "High Quality"

 

[dingbat]

Blues Seas recommends 6 AWG for charging systems 60A or less to protect from overheating the ACR.

https://d2pyqm2yd3fw2i.cloudfront.net/files/resources/instructions/990170140.pdf

 

[hpwells1]

Thank you all Problem solved.

 

[Thirsty Endgrain]

How?

 

[hpwells1]

by installing a ACR and "not" touching the wiring in my motor for another rectifier. My batteries are good. When docked,they are connected to a OBC. I wanted my house battery to be completely unattached from my starter battery and now I have that.