Over our almost 5 years of owning our 550, including 195 nights and a bit more than 49k miles, we've done a lot of dry camping. We've frequently moved from dry camp to dry camp, 'cause, well, that's where the best camping is.
I killed the original AGM battery in about a year and a half by not getting it fully charged often enough. I just didn't know what I was doing. The problem was using a dometic fridge and thinking that 6+ hours of driving between campsites would charge up the battery fully. I sure was wrong. Car alternators just don't give AGM batteries what they need to get truly a full charge, I don't care how long you drive.
So when I replaced that battery I added a trimetric battery monitor and have worked hard to get the battery fully charged every five days or less. We use a solar panel so sometimes that does it if we're in a nice sunny spot. Other times we've opted to find a campground with shore power just to get a full charge.
This is not optimal camping for us. We like to get out there and stay out there. Most forest service campgrounds and pretty much all national parks are dry camping only.
When I read on this forum about the CTEK charger I was intrigued. A really full charge on the battery when I get to the campground? That's a game-changer for us.
I inquired of Cary about how Camp Inn feels about these chargers and he replied strongly in the affirmative. We talked about possible mounting locations (they mount them in the curbside galley storage bin) and I ordered one up and installed it.
I really didn't want this charger mounted in the galley storage so I decided to give mounting it over the battery a try.
Here's what it looked like before the CTEK was installed. Above the battery to the right is the battery isolator. That can be eliminated by using the CTEK. The small device to the left is the shunt for the trimetric.
I removed these devices and this is what it looked like. The shunt will have to be remounted.
I had to add a strip of wood to give me a place to mount the CTEK.
The CTEK was easy to install at this point but I had to install it "upside down" because the power wire from the seven way plug wasn't long enough and I didn't want to splice it (hope no electrons spill out). I also had to use a small round file to open up the ring terminals because the CTEK mounting studs are bigger than those on the now-removed battery isolator. I made a new wire to run from the CTEK output stud to the 50 amp breaker because the existing wire just wasn't quite long enough.
Here's what it looks like installed. It's pretty tight with the trimetric shunt but it all fits fine. You can see the CTEK temperature probe taped to the top of the battery near the positive post. That's how they say to do it.
I've only tested it briefly because my January southern Arizona camping trip got canceled by a DC hissy fit. The trimetric voltage came right up and the amps started high (around 10) but quickly settled back to 3-4 and came down steadily from there. The battery wasn't very discharged so I didn't expect the amps to be very high.
The only other details I can think of is that there's a wire from the CTEK you have to ground if you have an AGM battery. That was easy enough. There's also another wire to tell the unit that you have a "smart alternator" (we don't) and I'm not sure how that gets hooked up. We may be getting a new TV this spring so I guess I'll find out.
If I can get out on the road in March I'll get some more data and report further.
Robert Dickson
550 #645
I killed the original AGM battery in about a year and a half by not getting it fully charged often enough. I just didn't know what I was doing. The problem was using a dometic fridge and thinking that 6+ hours of driving between campsites would charge up the battery fully. I sure was wrong. Car alternators just don't give AGM batteries what they need to get truly a full charge, I don't care how long you drive.
So when I replaced that battery I added a trimetric battery monitor and have worked hard to get the battery fully charged every five days or less. We use a solar panel so sometimes that does it if we're in a nice sunny spot. Other times we've opted to find a campground with shore power just to get a full charge.
This is not optimal camping for us. We like to get out there and stay out there. Most forest service campgrounds and pretty much all national parks are dry camping only.
When I read on this forum about the CTEK charger I was intrigued. A really full charge on the battery when I get to the campground? That's a game-changer for us.
I inquired of Cary about how Camp Inn feels about these chargers and he replied strongly in the affirmative. We talked about possible mounting locations (they mount them in the curbside galley storage bin) and I ordered one up and installed it.
I really didn't want this charger mounted in the galley storage so I decided to give mounting it over the battery a try.
Here's what it looked like before the CTEK was installed. Above the battery to the right is the battery isolator. That can be eliminated by using the CTEK. The small device to the left is the shunt for the trimetric.
I removed these devices and this is what it looked like. The shunt will have to be remounted.
I had to add a strip of wood to give me a place to mount the CTEK.
The CTEK was easy to install at this point but I had to install it "upside down" because the power wire from the seven way plug wasn't long enough and I didn't want to splice it (hope no electrons spill out). I also had to use a small round file to open up the ring terminals because the CTEK mounting studs are bigger than those on the now-removed battery isolator. I made a new wire to run from the CTEK output stud to the 50 amp breaker because the existing wire just wasn't quite long enough.
Here's what it looks like installed. It's pretty tight with the trimetric shunt but it all fits fine. You can see the CTEK temperature probe taped to the top of the battery near the positive post. That's how they say to do it.
I've only tested it briefly because my January southern Arizona camping trip got canceled by a DC hissy fit. The trimetric voltage came right up and the amps started high (around 10) but quickly settled back to 3-4 and came down steadily from there. The battery wasn't very discharged so I didn't expect the amps to be very high.
The only other details I can think of is that there's a wire from the CTEK you have to ground if you have an AGM battery. That was easy enough. There's also another wire to tell the unit that you have a "smart alternator" (we don't) and I'm not sure how that gets hooked up. We may be getting a new TV this spring so I guess I'll find out.
If I can get out on the road in March I'll get some more data and report further.
Robert Dickson
550 #645
