jointcustody
Veteran Member
Hi there,
If i have to draw diagrams I am ready to do that...I am going to do my best to get this all across lol.
I currently have a 34ft CHB trawler with a perkins 135 diesel. It's the boat in my sig. I have a 12v house bank that is 2 sets of 2-6v gc batteries, new 10 months ago. So 4 batteries wired to a 3 position switch that is always left on "both" so for simplicity lets just say i have a 416ah 12v house bank. I have barely cycled these house batteries. Maybe 30 cycles.
I have a 12v windlass in the bow. There is old 4/0 wiring ran from my house bank to the windlass. 25-30ft including bends.
I have a separate 12v 4d battery for starting the perkins.
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I am adding a sideshift ss350 24v bow thruster. It is already purchased. I need to add 2-12v AGM's in the bow to feed it 24v. I also want to feed my windlass with one of the batteries- so connect to just one of them. I don't really want to rewire my windlass motor to 24v (assuming thats possible- its old) because I have a spare windlass motor. I have read that you can use a battery equalizer to balance them and they should be fine. For charging, I think victron offers a 12-24v dc-dc charger that I could run from my 12v alternator to the 24v bank to charge. Heres where it gets trickier...
My 4d starting battery is getting older... like 8-9 years old. I want to use this opportunity to remove it, and potentially rewire. I'd like to add two more gc batteries to increase my house bank to 624 ah (using the battery box that my starting battery had)
Assuming everything is ok up until this point, should I use the 4/0 cable from my bow, shorten it up and renew the ends... run it from the OTHER 12v battery in the bow, (the other side of the 24v setup) as my engine starting battery (and maybe go large on these batteries?)
Is it a bad idea to remove the engine start battery?
Or should I start this engine with my new larger house bank? (surely theres enough cranking amps now???) with an emergency parallel switch to one of the agm's in the bow should the house bank go dead- maybe two switches- one to shut off the depleted house bank, the other to turn on the emergency start from the AGM to the perkins- then you could close the house bank back in and begin charging it (but could destroy my 12-24 charger in the process?)
I have read that my perkins should have two 750 cca 12v batteries in parallel for a dedicated starting battery, but that it will start just fine with one. It is only with sustained cranking that you need to have two. I will be installing two 850cca AGM's in the bow for the thruster. So in a situation where someone goofed up and the house bank was completely flat, the single 12v agm would start it fine.
I should also say, that I have a diesel genset that I could start as well to run the battery chargers in such a situation.
To me- it seems like I got enough 12v batteries around that surely I dont need to have a dedicated one for starting at this point????
I am a powerline technician (lineman) by trade so I understand the basics, but I deal with AC at work.
Sorry, Thanks lol
If i have to draw diagrams I am ready to do that...I am going to do my best to get this all across lol.
I currently have a 34ft CHB trawler with a perkins 135 diesel. It's the boat in my sig. I have a 12v house bank that is 2 sets of 2-6v gc batteries, new 10 months ago. So 4 batteries wired to a 3 position switch that is always left on "both" so for simplicity lets just say i have a 416ah 12v house bank. I have barely cycled these house batteries. Maybe 30 cycles.
I have a 12v windlass in the bow. There is old 4/0 wiring ran from my house bank to the windlass. 25-30ft including bends.
I have a separate 12v 4d battery for starting the perkins.
--------------------------------------
I am adding a sideshift ss350 24v bow thruster. It is already purchased. I need to add 2-12v AGM's in the bow to feed it 24v. I also want to feed my windlass with one of the batteries- so connect to just one of them. I don't really want to rewire my windlass motor to 24v (assuming thats possible- its old) because I have a spare windlass motor. I have read that you can use a battery equalizer to balance them and they should be fine. For charging, I think victron offers a 12-24v dc-dc charger that I could run from my 12v alternator to the 24v bank to charge. Heres where it gets trickier...
My 4d starting battery is getting older... like 8-9 years old. I want to use this opportunity to remove it, and potentially rewire. I'd like to add two more gc batteries to increase my house bank to 624 ah (using the battery box that my starting battery had)
Assuming everything is ok up until this point, should I use the 4/0 cable from my bow, shorten it up and renew the ends... run it from the OTHER 12v battery in the bow, (the other side of the 24v setup) as my engine starting battery (and maybe go large on these batteries?)
Is it a bad idea to remove the engine start battery?
Or should I start this engine with my new larger house bank? (surely theres enough cranking amps now???) with an emergency parallel switch to one of the agm's in the bow should the house bank go dead- maybe two switches- one to shut off the depleted house bank, the other to turn on the emergency start from the AGM to the perkins- then you could close the house bank back in and begin charging it (but could destroy my 12-24 charger in the process?)
I have read that my perkins should have two 750 cca 12v batteries in parallel for a dedicated starting battery, but that it will start just fine with one. It is only with sustained cranking that you need to have two. I will be installing two 850cca AGM's in the bow for the thruster. So in a situation where someone goofed up and the house bank was completely flat, the single 12v agm would start it fine.
I should also say, that I have a diesel genset that I could start as well to run the battery chargers in such a situation.
To me- it seems like I got enough 12v batteries around that surely I dont need to have a dedicated one for starting at this point????
I am a powerline technician (lineman) by trade so I understand the basics, but I deal with AC at work.
Sorry, Thanks lol
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