Upgrading my charging system, I know crap about electrical.

[hidesertwheelin]

What I am wanting to do:

I'm looking to upgrade my electrical charging system on my 2000 LX470, but my knowledge is jack crap. I currently run a dual battery system with a regular old interstate battery for the starting battery and a Optima yellow top as the house battery. I currently run a National Luna intelligent solenoid and battery controller. I have my winch mounted to the starting battery, and I am planning on wiring a Blue Sea fuse block in the back to power my Snomaster 67qt expedition fridge, cpap (without humidifier), and misc charging ports. I am wanting to add a 100 watt solar panel to the mix (still deciding on a fixed mount or a suitcase model). I also have a off-road trailer that I will eventually be adding batteries to. I had a wire ran to my 7 wire plug from the battery to charge those batteries while driving. I also had a low power cut off wired in to stop it from bleeding the starting battery while off. I plan to add a DC to DC charger w/ a shore power option whenever I get to that project.


Questions:

Should I add a DC to DC charger? Do I really need one? I saw the video from Andrew St. Pierre about how intelligent solenoids are not efficient, after I had installed mine. Should my current system work well enough? I need to buy a solar charger anyways, so I was considering getting one with DC to DC charging abilities since I was buying one anyways.

Is there a wire sizing guide for dummies that explains things in dummy terms?

Solar panels, fixed or suitcase? Opinions and why?

Anything else I should know that I don't? I've read through a lot of electrical post on forms, and it's mostly people arguing about over why a certain system design is crap vs good, and it just left me confused as all hell.

Thanks for any input.

 

[smritte]

Start with the basic's. Lets do alternator first. Solar and controllers are secondary.

1. Average vehicle draw driving down the road, at night, wipers on, will be around 25 amps.
2. Average low battery draw 40 amps. This will decrease as it charges.
3. Add 40 amps per extra battery you add in.
4. Look up the spec on your vehicle. Its advised to stay below 80% of your alternators max output.
5. The hard part is finding the proper alternator.
6. Once you figure out how much power needs to go where, there are wire sizing charts.

There's your charging system.

On older vehicles the power can fluctuate. This could cause issues with some equipment as well as some lithium batteries. If your stepping up to a custom modern alternator, that shouldn't be an issue. Modern charge controllers take the guesswork out and do a good job of isolating. Solar can be run at the same time with no ill effect if set up properly. At best it can take some load off the alternator. That's assuming you leave it attached to the roof. I have a single 120 watt for my trailer. I wish I had two smaller ones. Way easier to store. It only comes out when the trailer sits for more than a day.

Your not going to notice whether or not intelligent solenoids are efficient. The loss is minimal.

If I'm not mistaken, we have met. Next outing we could sit and talk if you want and I could help you put a list together for your build. None of this is actually very difficult.

Scott

 

[mylilpwny]

This really can be vehicle and battery dependent. Some vehicles ( alternator) can handle this just fine as Scott pointed out some can't. It also depends on the battery if it is lead acid, agm or lithium/other. Alternators are great for lead acid, can work ok to well for agm and meh on lithium. The reason why most suggest a DC to DC or charge controller is it takes a lot of the guess work out and works with a more broad range of applications. They are also designed to charge the type of battery you have, as in agm. I have had myself as well as friends run agms off the alternator with decent results. if that is a route you want to go it can be cheaper than buying a charge controller but i would add a at home battery charger. this is what i did as it helps to keep the battery conditioned properly, my old yellow top that i bought back in 06 lasted 9 years with this set up. optima sells pretty good chargers that work with both lead acid and agm to charge accordingly. the other downfall is that your alternator is designed to charge a starting battery and not a deap cycle , contrary to some belief rhat a battery is a battery, they have a different way they accept a charge especially at low to dead levels. you will get better performance and more out of your battery if you use a dc to dc but that doesnt mean you will hate the results with strait alternator charging. i did it for many years.

 

[hidesertwheelin]

If I'm not mistaken, we have met. Next outing we could sit and talk if you want and I could help you put a list together for your build. None of this is actually very difficult.

Scott

Scott,

Sorry I never got a notification anyone had replied to this. I'm don't think we have meet, but I always want to check out other cruisers. I ended up mounting a 100 watt Renogy panel, and a Blue Solar MPPT Charger to a old Optima Yellow Top I had sitting around. I ran my Snomaster fridge for all of expo, so it works good enough.

 

[smritte]

Scott,

Sorry I never got a notification anyone had replied to this. I'm don't think we have meet, but I always want to check out other cruisers. I ended up mounting a 100 watt Renogy panel, and a Blue Solar MPPT Charger to a old Optima Yellow Top I had sitting around. I ran my Snomaster fridge for all of expo, so it works good enough.

Glad it worked out. I guess I was mistaken. You reminded me of one of the guys from the inland empire group. Im not too far from you and I try to get out regularly. I'm always looking for people to go camping/exploring with.

Scott

 

[hidesertwheelin]

Glad it worked out. I guess I was mistaken. You reminded me of one of the guys from the inland empire group. Im not too far from you and I try to get out regularly. I'm always looking for people to go camping/exploring with.

Scott

I've been to one IE group meeting, and it was the one at the end last year. Now that my kids soccer is over, hopefully I can get out more.