General Forum Advice?

[farmbyforty]

Hi everyone.

I joined this forum a while ago and I read threads on here often, but as an electrical beginner (try mega-beginner) I'll admit many of the posts/replies go way over my head, though I'm doing my best to learn quickly. I'd like to start being active on this forum now that I'm getting into the "nitty gritty" of planning my electrical system. I figure the more eyes and opinions on my planed system, the better. I will probably ask a lot of very stupid/obvious questions, so thank you in advance for your patience and understanding.

I'm currently working on designing a 24v electrical system for a conversion of a ram promaster cargo van. I've gotten a lot of electrical help over at the promaster forum so far. If I'm not mistaken, quite a few of the PM forum members are also members here. I've believe I've seen @RV8R , @HarryN , and @GaryBIS around. Apologies if I'm tagging the wrong people. Their assistance on the PM forum has been invaluable to me. Hoping to forge similar electrical allies here as well

Since every forum is different, I value your advice about how to get the most out of the DIY Solar Forum without being bothersome to others. Any taboos, unwritten rules, secret rituals I should know about?

I'm planning to post my questions in the Vehicle Mounted Systems forum, unless y'all think it's better to keep them here in the beginner corner?

Thanks in advance for your help -- I look forward to learning from you all!

 

[robbob2112]

Read a lot - Chances are every question you have has been answered before - but if you can't find the answer start a thread

Don't hijack a thread - we always somehow seem to go off the rails, but we try to stay on track until the OPs original question has been answered.

See my answer thread below there is a lot of information in there about different areas -- there are different designs - some need updating that are old and I will get around to it one day -

Make sure to pay attention to the tools section - buy quality tools and you won't go wrong - buy cheap tools and you will buy replacements when the results suck... this particularly goes for the hydraulic crimpers... and buy a good DC clamp meter - it sucks to be troubleshootin something and you aren't sure if your meter is good or bad.

 

[HarryN]

Here is the forum section related to mobile / automotive such as vans.

Vehicle Mounted Systems

RV's, Vans, Trucks and More! Typically 12v, and 100-1000w, but the limits are endless!

diysolarforum.com

I know that there is a trend for people to go on multiple forums and ask the same questions. I am not sure if that is better or not.

It is similar to going to a big Thanksgiving dinner and asking everyone there what color to paint the walls.

Then asking the same question again at Christmas and Easter.

If you try to blend all of the answers together, and buy all of the suggested paint colors, then it can be confusing.

Instead, I just have my wife do all of the color choice stuff and I do the painting. It doesn't really matter that much, as long as you can reach a decision.
______________

@robbob2112 s comment about tools is dead on. Honestly for many people, it is not worth buying the tools - they should try to find someone with them if possible.

 

[upnorthandpersonal]

Remain on topic in threads, keep religion, politics, etc. out of the thread: it will derail, and be moved to chit-chat (as you are new here, some advice: don't go down there).

Welcome!

 

[Rednecktek]

If you ask about a specific piece of equipment you're looking at, post a link to the equipment so we can see the specs. Saves a LOT of time trying to guess.

Sketches, diagrams, even krappy MSPaint pics can be handy.

Let me throw my blurb in here too, it helps point towards the right direction.

Don't buy anything until you have a plan!

Stay away from the Chit-Chat section if you value your sanity.

Don't ask about grounding if you value your sanity.

 

[Rednecktek]

Blurb time!

Well, I'll start the default answer to these questions and we can work from there. Here's you To-Do list:

1: Power audit! This will give you some important information on how big your inverter needs to be as well as how much battery capacity you'll need. There is a link in the FAQ section (I think, or someone here will post it shortly) so fill in the blanks and see what it comes up with. You'll probably need some sort of Kill-A-Watt to get accurate measurements. Are you going to be running a 12v system? 24v system? 48v system? What are the specs on your solar panels? VoC? Vmp? Being as this is a new build, throw together a wish list of what you want and estimate on the high side.

1a: Where do you live? Speccing out a system for Scotland is a LOT different numbers than Arizona due to the amount of light you actually get. Someone here can post the link to the PVwatts.com or JCR Solar Uber-Sun-Hours calculator sites to help figure out how much you'll have to work with. That will be a box in the Power Audit form.

2: Parts list: You don't need a make & model list, just a parts list to start from for reference. You'll need an inverter, a MPPT charge controller, fuses, shunt, buck converter, batteries, wire, etc. Once you have a basic list it can be fine tuned to make & models after that. If you're looking at the All-In-Ones check for correct voltage outputs (120v or 240v Split Phase for North America, 220v Single Phase for European type areas) and make sure it has enough capacity for a little bit of growth and fudge factor.

3: Budget!: Steak is great but doesn't mean anything if your wallet says hamburger. Figure out what you're able to spend now vs what you'll have to cheap out on now and upgrade later.

4: Tape measure! Figure out where you're going to stick all the stuff you'll need. A dozen 3000AH batteries sounds great until you're sleeping on the floor because there's no room left for a bed. Is there a compartment that can house all this stuff? Will the server rack batteries fit? Are you going to have to make space? Physics can be pretty unforgiving.

5: Pencil out what you think you need and throw it at us so we can tell you what you've missed (because we ALL miss stuff the first go-round ) and help figure out which parts and pieces you're going to want to get.

Well that's the thing about solar systems, there is no 1-Size-Fits-All answer. Your system will need to be designed to fit YOUR needs. When you design and built the system, it's not going to be the perfect system for me, or Will or 12vInstall or anyone else, but it Will be the right system for You and that's the goal.

As for where to get started, let me throw my standard blurb in here to help point you in the right direction. There's going to be a lot of math and research involved, but that's going to be a LOT cheaper than just buying parts off of someone's list and finding out that it doesn't do what you need.

Don't panic on the Power Audit, you'll actually be doing that a few times. When you do the first pass put in ALL the Things that you might want. AirCon? Sure. Jacuzzi? Why not. MargaritaMaster-9000? Go for it.

The second pass will be the "I Absolutely Need This To Survive" list that isn't going to have much on there.

The third pass will be the "This is what is realistic" audit that you'll use to design the rest of the system.

The Power Audit is going to tell you 3 primary things: 1: How big does your inverter need to be to power your loads? 2: How much battery bank do you need to last $N number of days with krappy weather? and 3: How much solar panel will I need to install to refill those batteries in a 4 hour day (the average usable sun hours rule-of-thumb).

Once you know what you Want and what you Need and what your budget can Afford there will be somewhere in that Venn diagram where those three things meet.

After that, THEN you can start looking at parts.

Yes, it's a long drawn out process, but it's worth it in the end. Not every house has the exact same floorplan, not every vehicle is the same make & model, and not every solar system is designed the same.

Another thing to consider when doing your power audit is HOW you use your power. As a great example, we had a new user on here a while back trying to figure out power for his tiny home. He ran through the power audit multiple times and kept coming up with needing a 10kw+ inverter for a tiny home.

I pointed out that if he promised NOT to make espresso in the blender while frothing it in the microwave while his hair dryer was going, he could easily get away with a 3kw unit.

So, HOW you use your power is also a significant part of designing a system. If there was one single design that worked for everyone, there would only be one system for sale.

 

[robbob2112]

Blurb time!

Well, I'll start the default answer to these questions and we can work from there. Here's you To-Do list:

1: Power audit! This will give you some important information on how big your inverter needs to be as well as how much battery capacity you'll need. There is a link in the FAQ section (I think, or someone here will post it shortly) so fill in the blanks and see what it comes up with. You'll probably need some sort of Kill-A-Watt to get accurate measurements. Are you going to be running a 12v system? 24v system? 48v system? What are the specs on your solar panels? VoC? Vmp? Being as this is a new build, throw together a wish list of what you want and estimate on the high side.

1a: Where do you live? Speccing out a system for Scotland is a LOT different numbers than Arizona due to the amount of light you actually get. Someone here can post the link to the PVwatts.com or JCR Solar Uber-Sun-Hours calculator sites to help figure out how much you'll have to work with. That will be a box in the Power Audit form.

2: Parts list: You don't need a make & model list, just a parts list to start from for reference. You'll need an inverter, a MPPT charge controller, fuses, shunt, buck converter, batteries, wire, etc. Once you have a basic list it can be fine tuned to make & models after that. If you're looking at the All-In-Ones check for correct voltage outputs (120v or 240v Split Phase for North America, 220v Single Phase for European type areas) and make sure it has enough capacity for a little bit of growth and fudge factor.

3: Budget!: Steak is great but doesn't mean anything if your wallet says hamburger. Figure out what you're able to spend now vs what you'll have to cheap out on now and upgrade later.

4: Tape measure! Figure out where you're going to stick all the stuff you'll need. A dozen 3000AH batteries sounds great until you're sleeping on the floor because there's no room left for a bed. Is there a compartment that can house all this stuff? Will the server rack batteries fit? Are you going to have to make space? Physics can be pretty unforgiving.

5: Pencil out what you think you need and throw it at us so we can tell you what you've missed (because we ALL miss stuff the first go-round ) and help figure out which parts and pieces you're going to want to get.

Well that's the thing about solar systems, there is no 1-Size-Fits-All answer. Your system will need to be designed to fit YOUR needs. When you design and built the system, it's not going to be the perfect system for me, or Will or 12vInstall or anyone else, but it Will be the right system for You and that's the goal.

As for where to get started, let me throw my standard blurb in here to help point you in the right direction. There's going to be a lot of math and research involved, but that's going to be a LOT cheaper than just buying parts off of someone's list and finding out that it doesn't do what you need.

Don't panic on the Power Audit, you'll actually be doing that a few times. When you do the first pass put in ALL the Things that you might want. AirCon? Sure. Jacuzzi? Why not. MargaritaMaster-9000? Go for it.

The second pass will be the "I Absolutely Need This To Survive" list that isn't going to have much on there.

The third pass will be the "This is what is realistic" audit that you'll use to design the rest of the system.

The Power Audit is going to tell you 3 primary things: 1: How big does your inverter need to be to power your loads? 2: How much battery bank do you need to last $N number of days with krappy weather? and 3: How much solar panel will I need to install to refill those batteries in a 4 hour day (the average usable sun hours rule-of-thumb).

Once you know what you Want and what you Need and what your budget can Afford there will be somewhere in that Venn diagram where those three things meet.

After that, THEN you can start looking at parts.

Yes, it's a long drawn out process, but it's worth it in the end. Not every house has the exact same floorplan, not every vehicle is the same make & model, and not every solar system is designed the same.

Another thing to consider when doing your power audit is HOW you use your power. As a great example, we had a new user on here a while back trying to figure out power for his tiny home. He ran through the power audit multiple times and kept coming up with needing a 10kw+ inverter for a tiny home.

I pointed out that if he promised NOT to make espresso in the blender while frothing it in the microwave while his hair dryer was going, he could easily get away with a 3kw unit.

So, HOW you use your power is also a significant part of designing a system. If there was one single design that worked for everyone, there would only be one system for sale.

I want to blurb ... I want to blurb!!

Post in thread 'Robbob2112 Answer thread'

Jan 14, 2025

Standard Blurb

Don't spend any money, until you have planned out the entire system. An eraser is cheap, but returns can be costly.

Planning

1. Energy Audit - what do you have to power?
2. Size the inverter for your maximum instantaneous demand (including surges).
3. Size the battery for how long you want power, when the sun isn't shining.
4. Size the PV to cover the loads and recharge the battery, when the sun is shining for your area - most in the US use 4hrs or 5 hours a day of sun
5. Trying to use old equipment you already have usually costs more in design compromises than just...

• robbob2112

• 

 

[RV8R]

Hi everyone.

I joined this forum a while ago and I read threads on here often, but as an electrical beginner (try mega-beginner) I'll admit many of the posts/replies go way over my head, though I'm doing my best to learn quickly. I'd like to start being active on this forum now that I'm getting into the "nitty gritty" of planning my electrical system. I figure the more eyes and opinions on my planed system, the better. I will probably ask a lot of very stupid/obvious questions, so thank you in advance for your patience and understanding.

I'm currently working on designing a 24v electrical system for a conversion of a ram promaster cargo van. I've gotten a lot of electrical help over at the promaster forum so far. If I'm not mistaken, quite a few of the PM forum members are also members here. I've believe I've seen @RV8R , @HarryN , and @GaryBIS around. Apologies if I'm tagging the wrong people. Their assistance on the PM forum has been invaluable to me. Hoping to forge similar electrical allies here as well

Since every forum is different, I value your advice about how to get the most out of the DIY Solar Forum without being bothersome to others. Any taboos, unwritten rules, secret rituals I should know about?

I'm planning to post my questions in the Vehicle Mounted Systems forum, unless y'all think it's better to keep them here in the beginner corner?

Thanks in advance for your help -- I look forward to learning from you all!

Welcome @farmbyforty !!

I will look for your posts

 

[Sparks-n-Splinters]

Welcome @farmbyforty

One of the biggest things that has helped me is a note pad and pen. There are a million acronyms and abbreviations, names and model numbers that all got muddled around in my head until I put them on paper.
Sometimes it felt like I was trying to read about quantum physics in Latin until I had a cheat sheet to pull out!

I spend hours and hours wading thru search results here and don't think I have had a question yet that was not at the very least addressed in some for or another. I'm still a long way from being a pro around here, but I'm getting there slowly.

 

[RV8R]

Welcome @farmbyforty

One of the biggest things that has helped me is a note pad and pen. There are a million acronyms and abbreviations, names and model numbers that all got muddled around in my head until I put them on paper.
Sometimes it felt like I was trying to read about quantum physics in Latin until I had a cheat sheet to pull out!

I spend hours and hours wading thru search results here and don't think I have had a question yet that was not at the very least addressed in some for or another. I'm still a long way from being a pro around here, but I'm getting there slowly.

I have liked Victron’s Wire Unlimited as a guide for newbies.

https://www.victronenergy.com/upload/documents/The_Wiring_Unlimited_book/43562-Wiring_Unlimited-pdf-en.pdf

I love the “Characters” . Just look at that menacing cowboy

Volts & Amps look like they have a symbiotic relationship ,,, “Let’s Help Each Other” to Getter Done !! “Hey Amps are you experiencing some “resistance” in your work ,,, let me help your thru it

 

[farmbyforty]

@robbob2112 @HarryN @upnorthandpersonal @Rednecktek @RV8R @Sparks-n-Splinters

Thank you for taking the time to offer your input and helpful advice! I really appreciate it. I'm looking forward to participating in the community here and learning as much as I can

 

[robbob2112]

If it hasn't been mentioned... Solar is addicting... prepare the crowbarand lubricate it frequently, you will need it to pry open the wallet and if it is rusty it doesn't work very well...

And keep the significant other happy... it helps when the crowbar time comes.