Starting point for cheapskate electrical system?

Boy, there are a lot of complicated schematics out there. Can someone point me to a simple 12v one with relatively inexpensive components?
Load:
Maxxair fan
On-demand pump for simple 5 gal water system
Phone chargers
A few small task LED lamps (if we stay up after dark, we tend to be outside)
A small inverter so I'm able to charge a laptop when I'm not on shore power
Battery:
Probably a 100 ah AGM, maybe expanding to a 2nd at some point
Charging systems:
Something like a Renogy 100 watt solar kit, with room to expand to no more than 300 watt total
Charging from shore power
Charging from alternator while driving

I'm familiar with shore power wire sizing from designing and building my house, garage, and workshop, I know 12v load wire sizing and fusing from my boat, but charging systems are new to me.

Where I really need help is selecting inexpensive components and getting the charging system(s) to work well together. I would appreciate suggestions helping me find schematics on this forum that are attuned to my very basic needs.
 

BrennWagon

He’s just this guy, you know?
That’s a whole can of worms :ROFLMAO: The easiest and cheapest setup is to run a battery isolator you charge off of your alternator. Adding solar and shore power complicates things significantly and will require different controllers, so decide what your final system will consist of before you start buying components
 

dbuzz77

Dbuzz77
I have a fairly simple system powering your stuff plus a microwave and a fridge so i have a 220ah battery with a 3000w xantrex inverter and a progressive dynamics 80a converter. i have a 4/0 cable from the truck battery with a switch to disconnect when on shore power. you might go with smaller inverter or converter for less load.
 

autostaretx

Erratic Member
Here's mine ... $350 for 200 watt solar, not counting cost of existing 67 AH (yes, too small) battery, $99 (then) shore-powered charger, $99 1000 watt inverter (in 2006).


Adequate to power a 600 watt microwave plus Engel 40 liter fridge.
--dick
p.s. link has parts list with prices, wiring diagram, installation photos
p.p.s. agreeing with Vanski's comment ... i "chose" my components (heck, i bought the battery, shore-charger and inverter in 2006) with the full acceptance that i may (or would) be changing them out or upgrading as i gained experience. Battery size was chosen in part for "liftability" ... i knew i'd be taking it in and out of the Sprinter as we flipped between "camping" and "full cargo".
Different strokes for different folks.
 
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vanski

'05 Box Snow Camper
imo.. the real question isn't what is the cheapest install... but what is the cheapest, and most trouble free, install over a five+ year time period.

so what's the most expensive component of most camper electric systems??? usually the batteries. and what are the components that many people need to replace most often.. the batteries... why do the batteries need to be replaced.. because they suffered from sulfation.. case in point, i recently put in a system for someone replacing 2x Northstar sms agm480 batteries. These batteries are $800+tax+shipping each. They are some of the best AGM batteries on the market. But, if you sulfate them badly, game over. He sulfated them in 2 months of ownership!!! So, you either need to implement a system which doesn't allow the batteries to sulfate.. that's a big conversation. or, you install batteries that can be revitalized if they do sulfate.. or batteries which don't really sulfate such as Lithium.

Lifeline AGM batteries are the only AGM battery to my knowledge which have a realistic ability to be revitalized to a reasonable capacity once they've been severely sulfated. they use an equalization charge to do this.. you push the batteries up to 15.8v-16.4v for 8-10 hours. taking this a step further there are different solar charge controllers, such as Victron which is my favorite for a variety reasons, which can supply an qualization charge. This allows this ability without an expensive charger outside the rig. The Victron CCs can even have an automated monthly equalization charge setting applied. i'm personally a big fan of this capability.

so, i understand I didn't answer your question but folks really need to see the forest through the trees as it relates to cost of the system. not to mention the pain in the butt when things start failing when you really need them most, which is exactly when they will fail; been there!

google Will Prowse and watch some of his videos. He breaks DIY systems for beginners. He definitely has a focus on LFP (Lithium) systems for the most part, but he understands his audience are mostly budget buyers.
 

Wrinkledpants

Active member
Boy, there are a lot of complicated schematics out there. Can someone point me to a simple 12v one with relatively inexpensive components?
Load:
Maxxair fan
On-demand pump for simple 5 gal water system
Phone chargers
A few small task LED lamps (if we stay up after dark, we tend to be outside)
A small inverter so I'm able to charge a laptop when I'm not on shore power
Battery:
Probably a 100 ah AGM, maybe expanding to a 2nd at some point
Charging systems:
Something like a Renogy 100 watt solar kit, with room to expand to no more than 300 watt total
Charging from shore power
Charging from alternator while driving

I'm familiar with shore power wire sizing from designing and building my house, garage, and workshop, I know 12v load wire sizing and fusing from my boat, but charging systems are new to me.

Where I really need help is selecting inexpensive components and getting the charging system(s) to work well together. I would appreciate suggestions helping me find schematics on this forum that are attuned to my very basic needs.
Goal zero Yeti 400 + Walmart 150W 12v inverter (to charge the yeti). Connect yeti to the inverter, inverter to the cig plug under the cup holder. Charges automatically when you drive. Buy any sized portable solar panel you'd like, but we never needed it. We ran this way for a year. Had both our max fans wired to a single 12v plug that was powered by the Yeti.

Plus, resale is great if you go to sell this for a full electrical system.
 

Ulter

Member
Golf cart batteries from Costco, battery isolator to charge from alternator, Samlex/AIMS/Renogy or equivalent Chinese inverter/charger on Amazon, residential 60 cell solar panel (can find for $.50/Watt), $15 PWM solar charge controller on Amazon. That’s the cheapest system.
 

marklg

Well-known member
Golf cart batteries from Costco, battery isolator to charge from alternator, Samlex/AIMS/Renogy or equivalent Chinese inverter/charger on Amazon, residential 60 cell solar panel (can find for $.50/Watt), $15 PWM solar charge controller on Amazon. That’s the cheapest system.
Won't a 60 cell solar panel have too much voltage for a 12V PWM controller with 12V batteries? Are you suggesting a 24V system? Those inverters are harder to find.

Regards,

Mark
 

Ulter

Member
Won't a 60 cell solar panel have too much voltage for a 12V PWM controller with 12V batteries? Are you suggesting a 24V system? Those inverters are harder to find.

Regards,

Mark
Sorry yes too quick of a reply. $29 for an MPPT solar charge controller on Amazon.
 
imo.. the real question isn't what is the cheapest install... but what is the cheapest, and most trouble free, install over a five+ year time period.
<snip>
google Will Prowse and watch some of his videos. He breaks DIY systems for beginners. He definitely has a focus on LFP (Lithium) systems for the most part, but he understands his audience are mostly budget buyers.
Great reply. I initially typed "inexpensive, durable" and then got overzealous in editing my post.
At first glance it looks like a good lead on Will Prowse.
Thank you so much for taking the time to reply.
 

vanski

'05 Box Snow Camper
Np... just trying to share my personal experience with these systems and experience working with newbies ramping up such that they don’t waste money and time not to mention having their systems fail them when they are trying to enjoy time out on the road.

have fun..
 

autostaretx

Erratic Member
Sorry yes too quick of a reply. $29 for an MPPT solar charge controller on Amazon.
Could you provide a link to that cheap MPPT controller?
All of the hunting i did before my MPW purchase, and since, has always shown that MPPTs below $70 or more are usually incorrectly advertised (weasel words in the tiny print or manuals such as "acts like MPPT" (but not really)").
My plan has been to eventually replace my MPW with an MPPT if the "price-benefit" ever seemed to warrant it (i.e. if i put in different batteries or try a different panel wiring arrangement (series vs. current parallel)).

--dick
 

sparkplug

Member
I'm still undecided on buying an inverter because I think it's great thing to have but I don't really know what I would use it to power (therefore I can't calculate what size inverter I would want to buy).

Most laptops require low voltages to charge (which is why the charging cables have a transformer on them) and you should be able to find a 12v charging cable for them.

That's what I did for my MacBook. There are a few options out there so be sure to check you're buying the right one, but if that's the only reason for the transformer then a 12v cable will be the less expensive option.
 

Midwestdrifter

Engineer In Residence
This thread breaks down a high value electrical system for those with modest needs. Its probably larger than you need, but provides overhead for adding more loads later on, and should provide many years of reliable service at a decent powerpoint.
 

pfflyer

Active member
Boy, there are a lot of complicated schematics out there. Can someone point me to a simple 12v one with relatively inexpensive components?
Load:
Maxxair fan
On-demand pump for simple 5 gal water system
Phone chargers
A few small task LED lamps (if we stay up after dark, we tend to be outside)
A small inverter so I'm able to charge a laptop when I'm not on shore power
Battery:
Probably a 100 ah AGM, maybe expanding to a 2nd at some point
Charging systems:
Something like a Renogy 100 watt solar kit, with room to expand to no more than 300 watt total
Charging from shore power
Charging from alternator while driving

I'm familiar with shore power wire sizing from designing and building my house, garage, and workshop, I know 12v load wire sizing and fusing from my boat, but charging systems are new to me.

Where I really need help is selecting inexpensive components and getting the charging system(s) to work well together. I would appreciate suggestions helping me find schematics on this forum that are attuned to my very basic needs.
Your loads are the same as mine except I had a fringe in my van. There is not a lot of detail in The link in my signature Below but I have maybe $1000 in mine including the inverter. I think it is pretty simple even though I can power the inverter with the chassis battery or the house with a selector switch. I can charge the House battery while driving with a 7 stage charger powered by the inverter and chassis battery or simply combine the batteries with 1 switch. Shore power charging is done with the same 7 stage charger. No solar. I don’t have a fancy drawing of my system but I will dig up a hand drawn one if you are interested.
 

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