AGM Batteries - Bow Thruster (or not)

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osubux1

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Freedom 307
I need to replace my main batteries (4), and my AGM are due too (plus they are swelling up). My local service shop referenced the AGMs and said "as the AGMs power your bow thruster...". Now, I know they didn't go in and trace the wiring. I assume they are just guessing that is the case. When I look at the wiring diagrams in my 307 Freedom manual, it looks like the thruster is tied to the standard batteries. My Freedom does have AC (which we never use) in the head/storage area and those are tied to the AGMs. Regardless, because they are swelling I want to replace them. Just trying to piece the wiring together. (The boat is in FL and I am not, otherwise I could check)
Has anyone else had experience in this kind of setup?
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SkunkBoat said:
Are you saying you have AGM batteries that are not the main batteries pictured?
Click to expand...
Correct. In the stern, I have a row of 4 "regular" batteries (DEKA). Sitting in front of those are 2 AGM batteries. The manual shows the AC inverter layout tied to the AGM's.
 
You said AC, I thought Air Conditioning...not AC and a power inverter.
I don't have that and I don't have your manual but...

I assume you have shore power and AC panel? and an inverter to run (some) AC power from 2 AGM batteries when underway.
That is good that they are separate from DC side. You should not use an inverter on the "House" batteries when you have a shore power connection. You should have separate AC and Inverter AC circuits)(google that...)

You run what on the AC when not connected to shore power? Do you even need it?
 
SkunkBoat said:
You said AC, I thought Air Conditioning...not AC and a power inverter.
I don't have that and I don't have your manual but...

I assume you have shore power and AC panel? and an inverter to run (some) AC power from 2 AGM batteries when underway.
That is good that they are separate from DC side. You should not use an inverter on the "House" batteries when you have a shore power connection. You should have separate AC and Inverter AC circuits)(google that...)

You run what on the AC when not connected to shore power? Do you even need it?
Click to expand...
To be honest, I am not 100% sure of the setup. I assumed (possibly incorrectly) that "AC" referred to Air Conditioner because the pages are next to each other in the manual. And on the Air Conditioner page, it refers to many things as "AC".
1787874326259.png
 
So I'm assuming your AC runs on AC.... ;)
It runs on shore power at dock and on inverter AC power when underway? You use it at dock? you use it underway?
You have an AC breaker panel and a procedure for shifting to inverter AC power?
The AGMs charge from shore power charger? from Motors?

Your manual most probably explains it all. Sometimes there are separate manuals from the Air Conditioner manufacturer, Inverter manufacturer, etc...
 
I'm going to assume that the wiring on your 307 is similar to my 305. I have a generator for AC power when underway, while you have a battery bank and an inverter to get AC power while underway. If that's the case your thruster most likely works off one of your main battery banks as does mine. The AGM batteries are most likely just for the inverter and AC power. That being said without putting eyes on it, I cannot be a hundred percent sure. What year is the boat? How long have you owned it? If the setup you currently have is working for your uses, then I would be inclined to just do a direct replacement with what is currently installed with all batteries
 
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