coolfeet
Mark Keeler
After months of research and spending too much time thinking about a dual battery set up, I decided on the CTEK D250S as the isolator as it was almost idiot proof to install. It charges the battery with a real charge controller rather than relying on the alternator.
It has a built in charge controller for adding solar. I let my ARB fridge/freezer run for nearly 48 hours in 90 degree heat without killing my battery. I need solar for extended stays.
My friend who did the install cautioned me against connecting directly to the starting battery. While he said that it was the easiest, he reasoned that many vehicles already have fuses and relays built into them to the do the job. Why argue with an expert?
My friend engineer Dan pulled out the Ford shop manual and found a 40 amp fused trailer auxiliary battery relay built into the fuse box. He traced the wire and spliced in some SO cable for a quick connection.
I wanted to install the second battery on the frame rail of my Ford E150. My buddy convinced me that a removable battery box as the way to go as I could remove it and carry it with me. Great insight on his part as I moved the battery box several times. I have enough cord to move it anywhere in my van. It's currently sitting right behind the driver seat.
Here is a photo of my home made battery box:
I used 12/3 SOOW cable for my connections as it's wrapped in rubber and can withstand a beating. It's common AC commercial cable. I have about 20 feet of it and can pull the battery out of the van and use it for power. The quick connector makes it easy to pull the battery out.
I found a US made 6 pack fuse box. I install 6 30 amp fuses for the cigarette style outlets.
I added a dual USB port in one of the six 12 volt sockets-all purchase on eBay.
The QuickBox battery box cost $10.
The fuse and fuse box was another $15.
12 volt sockets including USB cost $20.
I got the SO cable and connections for free.
The CTEK D250S sells for $200 on Amazon.
After much research, I spent an extra $100 and bought the US made LifeLine 80 AH deep cycle marine battery. I found several similar Chinese made batteries for less money. I was getting tired of spending way too much time researching and went with the LifeLine as it seemed one of the favorites on the Expedition Portal. The connections are clean. It has a raised hollow top that enabled my friend to drill holes and mount the fuse fox!
It's no $50 dual battery system. However, with the flexibility of the CTEK unit, it's worth the extra money. I spent about $500 on the system including the $260 battery box. I plan on adding a 100W solar panel to run the system off grid when needed.
I have been camping for a week with the system and it's performed flawless.
I bought the CTEK 4.3 battery charger on Amazon for $60 because it's small, has quick connects for the battery, and can charge all my vehicle batteries at home.
The main source of power draw on this battery box is a 62 quart ARB fridge freezer. I set it to 0 degrees F while driving and 22 F at night.
I run 12 volt portable Fantastic Fan at night to keep my van cool.
This set up is my proto-type. I think a Busseman 30 circuit breaker may be cleaner. Daisey chaining the 6 fuses took some work.
I did not install a power invertor inside the box as I do not have much need for it. I strapped an old invertor on top the box for charging flashlight batteries. We have not charged a single battery yet as I have 2 Luci Light inflatable solar lanterns.
About the only use for my power invertor is for my burr coffee grinder which I did not take with because it's too big and heavy.
I bought a 12 volt power cord for our MacBooks. I have a 12 volt air mattress pump for pumping up the inflatable rafts that we did not take.
It has a built in charge controller for adding solar. I let my ARB fridge/freezer run for nearly 48 hours in 90 degree heat without killing my battery. I need solar for extended stays.
My friend who did the install cautioned me against connecting directly to the starting battery. While he said that it was the easiest, he reasoned that many vehicles already have fuses and relays built into them to the do the job. Why argue with an expert?
My friend engineer Dan pulled out the Ford shop manual and found a 40 amp fused trailer auxiliary battery relay built into the fuse box. He traced the wire and spliced in some SO cable for a quick connection.
I wanted to install the second battery on the frame rail of my Ford E150. My buddy convinced me that a removable battery box as the way to go as I could remove it and carry it with me. Great insight on his part as I moved the battery box several times. I have enough cord to move it anywhere in my van. It's currently sitting right behind the driver seat.
Here is a photo of my home made battery box:
I used 12/3 SOOW cable for my connections as it's wrapped in rubber and can withstand a beating. It's common AC commercial cable. I have about 20 feet of it and can pull the battery out of the van and use it for power. The quick connector makes it easy to pull the battery out.
I found a US made 6 pack fuse box. I install 6 30 amp fuses for the cigarette style outlets.
I added a dual USB port in one of the six 12 volt sockets-all purchase on eBay.
The QuickBox battery box cost $10.
The fuse and fuse box was another $15.
12 volt sockets including USB cost $20.
I got the SO cable and connections for free.
The CTEK D250S sells for $200 on Amazon.
After much research, I spent an extra $100 and bought the US made LifeLine 80 AH deep cycle marine battery. I found several similar Chinese made batteries for less money. I was getting tired of spending way too much time researching and went with the LifeLine as it seemed one of the favorites on the Expedition Portal. The connections are clean. It has a raised hollow top that enabled my friend to drill holes and mount the fuse fox!
It's no $50 dual battery system. However, with the flexibility of the CTEK unit, it's worth the extra money. I spent about $500 on the system including the $260 battery box. I plan on adding a 100W solar panel to run the system off grid when needed.
I have been camping for a week with the system and it's performed flawless.
I bought the CTEK 4.3 battery charger on Amazon for $60 because it's small, has quick connects for the battery, and can charge all my vehicle batteries at home.
The main source of power draw on this battery box is a 62 quart ARB fridge freezer. I set it to 0 degrees F while driving and 22 F at night.
I run 12 volt portable Fantastic Fan at night to keep my van cool.
This set up is my proto-type. I think a Busseman 30 circuit breaker may be cleaner. Daisey chaining the 6 fuses took some work.
I did not install a power invertor inside the box as I do not have much need for it. I strapped an old invertor on top the box for charging flashlight batteries. We have not charged a single battery yet as I have 2 Luci Light inflatable solar lanterns.
About the only use for my power invertor is for my burr coffee grinder which I did not take with because it's too big and heavy.
I bought a 12 volt power cord for our MacBooks. I have a 12 volt air mattress pump for pumping up the inflatable rafts that we did not take.
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