Questions regarding 48v work from home camper setup

[JoeInNV]

Hi everyone,



This is my first post, I saw some of Will Prowse’s videos on youtube a while back and bought his book. I don’t have any electrical experience, so after reading the book and watching the videos, there are a few concepts that I still don’t get, that I’m hoping this community can shine some light on. I reached out to a local electrician that was supposed to help me but he got busy with another job…and he didn’t have much experience with campers anyway…so I’m hoping the experts here can help.



I have a 2006 Everest camper that I want to wire up with solar. I originally planned on a 12v setup, so I bought all the parts listed here (https://www.mobile-solarpower.com/the-classic-400-watt-rvs-vans-buses.html), but now I think a 24v all in one setup (

) would suit me better. In that video, I saw that I can still use the two 12v batteries I got by hooking them up together…can I also do that with my 12v 200 watt solar panels so I can use them in a 24v system?



The 24v all in one that I want to get has the power plugs directly on it, but I was curious, when Will talks about wiring the 12v appliances to the fuse block here (

, and also shown in attached diagram) , is he talking about the microwave, lights etc on the camper, or things like computers, cell phone chargers, tvs? I’m still a bit confused on which devices can/should be plugged into the inverter using a normal power cord vs wired directly into the fuse block. I read that if a device will be used frequently, such as a work computer, it should be wired to the fuse block. I work from home and use a laptop, external monitor and internet dish for at least 10 hours a day…does that mean I should chop the end off the power cables for each of those devices and wire them directly to the fuse block like Will does in his videos?



The reason that I suddenly wanted to switch from 12v to 24v was because I looked at the power adapter for my laptop (see attached picture) and saw that it said 19.5v, so if I understand correctly, I would need a DC –DC converter to make that work. So my thinking was, because 19.5v is less than 24v, if I just get a 24v system I don’t have to bother with the converter and I just plug the power cable directly into the inverter…was I thinking about this correctly? Or would that not matter because it should still be spliced into the fuse block whether on 12v or 24v?

 

[caki]

You should use a dc-dc converter to power the laptop as 24v sometimes has higher voltages especially when charging the battery, like 27v.

 

[JoeInNV]

You should use a dc-dc converter to power the laptop as 24v sometimes has higher voltages especially when charging the battery, like 27v.

Hi caki, thanks for the reply! If I'm going with this 24v alll in one, would I still use a fuse block? I'm confused where the dc-dc converter would connect to using this all in one.

 

[caki]

Remember that a fuse is a protection for you wiring, so it doesn't melt and starts a fire if there is a short circuit. So any circuit that has the capacity to exceed the wire rating should have a fuse. Solar panels in the majority of cases don't use fuse because the wire can usually carry more power than the panels. So in your case, yes you should have a fuse block and all loads should be behind a fuse. Your dc-dc converter should have a fuse. Ideally all circuits should be fused

 

[Mattb4]

Just so it is clear. Do not connect AC voltage items to a DC fuse block. You also can not wire a 19.5 volt item to 24 volt supply unless it has a voltage range that allows it to go that high (24 volt batteries under charge can reach up to 30v). Yes you can connect panels in series to raise voltage.

 

[JoeInNV]

Just so it is clear. Do not connect AC voltage items to a DC fuse block. You also can not wire a 19.5 volt item to 24 volt supply unless it has a voltage range that allows it to go that high (24 volt batteries under charge can reach up to 30v). Yes you can connect panels in series to raise voltage.

Hi Matt,

Thanks for the reply! So it sounds like I can use my existing 12v batteries and panels with the MPP 24v all in one I want.

Just to make sure I'm understanding correctly, can I take my existing laptop power cord and simply plug it into the all in one AC plug? If I understand correctly, there would be power waste, but it would still work right?

 

[Charleswgibbs]

Hi Matt,

Thanks for the reply! So it sounds like I can use my existing 12v batteries and panels with the MPP 24v all in one I want.

Just to make sure I'm understanding correctly, can I take my existing laptop power cord and simply plug it into the all in one AC plug? If I understand correctly, there would be power waste, but it would still work right?

View attachment 116370

Existing panels and batteries will work with the all-in-one ? and yes you can plug your 120vac devices directly into the outlets on the unit.

As mattb4 mentioned make sure to keep 120vac and 12/24vdc items separate. The inverter will only output 120vac (although I think it also has USB plugs) so only connect it to devices with standard household plugs.

If you have any DC loads they must be connected directly to the battery (or fuse block, which then connects directly to battery)

Also worth noting that if you go with a 24v configuration you will need a 24v-12v dc-dc converter to power any 12v loads you have.

 

[JoeInNV]

Existing panels and batteries will work with the all-in-one ? and yes you can plug your 120vac devices directly into the outlets on the unit.

As mattb4 mentioned make sure to keep 120vac and 12/24vdc items separate. The inverter will only output 120vac (although I think it also has USB plugs) so only connect it to devices with standard household plugs.

If you have any DC loads they must be connected directly to the battery (or fuse block, which then connects directly to battery)

Also worth noting that if you go with a 24v configuration you will need a 24v-12v dc-dc converter to power any 12v loads you have.

Hi Charles, thanks for the reply! This is what I was confused about, I wasn't sure how the fuse block would connect to the all in one and batteries. Would I connect the black cable coming out of the MPP all in one to the top connection of the fuse block (labeled 1 in the picture below) and the red cable coming out of the MPP to the connection labeled 2 below?

 

[Charleswgibbs]

Hi Charles, thanks for the reply! This is what I was confused about, I wasn't sure how the fuse block would connect to the all in one and batteries. Would I connect the black cable coming out of the MPP all in one to the top connection of the fuse block (labeled 1 in the picture below) and the red cable coming out of the MPP to the connection labeled 2 below?






View attachment 116389


View attachment 116388

So you'll have a positive(red) and a negative(black) cable running from the battery's terminals to the inverter.

The easiest way to connect the fuse block is to run an additional positive and negative cable from the battery to the fuse block. So your battery will have two sets of cables coming from it, one set to the inverter and the other set to the fuse block.

You could also use busbars to connect everything up. If you go this route you only have one set of cables from the battery to the busbars, then one set of cables from the busbar to the inverter, and another set of cables from the busbars to your fuse block.

Using busbars isn't required for a simple system, it just makes a more tidy wiring layout.

Hope this helps!

 

[Rednecktek]

Normally the DC fuse block would connect directly between the battery Pos+ and the battery Neg- terminals in parallel with the AIO's battery connection... HOWEVER in your case since you're running a 24v system if you did that your fuse block would be feeding 24v to all your 12v appliances. That's what we call in the technology worlds as a, and forgive the highly technical terminology her, a "Bad Thing".

What you're going to need to do to feed your 12v stuff from your 24v battery bank is some flavor of 24v -> 12v converter that can provide enough amperage for whatever you're feeding from your fuse block. That'll kick down the 24v from the battery to the 12v the DC appliances call for.

The simplest option for the laptop is going to be just plugging the regular power brick into the outgoing 120v AC and letting it do its job, otherwise you've got to get adjustable converters involved and properly set and hope they hold out under load and all that complicated mess.

 

[JoeInNV]

Normally the DC fuse block would connect directly between the battery Pos+ and the battery Neg- terminals in parallel with the AIO's battery connection... HOWEVER in your case since you're running a 24v system if you did that your fuse block would be feeding 24v to all your 12v appliances. That's what we call in the technology worlds as a, and forgive the highly technical terminology her, a "Bad Thing".

What you're going to need to do to feed your 12v stuff from your 24v battery bank is some flavor of 24v -> 12v converter that can provide enough amperage for whatever you're feeding from your fuse block. That'll kick down the 24v from the battery to the 12v the DC appliances call for.

The simplest option for the laptop is going to be just plugging the regular power brick into the outgoing 120v AC and letting it do its job, otherwise you've got to get adjustable converters involved and properly set and hope they hold out under load and all that complicated mess.

Hi Rednecktek, thanks for the reply!

The 12v appliances are something else I was confused about.

I googled and found that some common 12v applliances are: Fridge, microwave, toaster coffeee maker ,kettle, blender, waffle maker, fans, lights. But what if I have, for example, a blender that plugs in with an AC cord...that would not be considered a 12v appliance right? Does "12v appliance" mainly refer to things in your camper that are hardwired such as the built in lights, water pump, water heater, etc ( aka not plugged in via AC?) I was looking at the cabinets in my camper and realized that the microwave just plugs into an AC outlet near the ceiling...so for the other things such as lights, would I need to disconnect the cables going into the existing camper fuse panel and re-wire them to my new solar fuse box?



And on a separate note, what about making use of the existing AC electrical outlets already in the camper? Would that require disconnecting them from the existing fuse panel and reconnecting them to the fuse box of the new solar setup? Or since I'm going with the all in one MPP, is it better to just ignore the existing camper AC outlets and just use extension cords/power strips for AC devices that plug into the AC outlets on the MPP?

 

[JoeInNV]

So you'll have a positive(red) and a negative(black) cable running from the battery's terminals to the inverter.

The easiest way to connect the fuse block is to run an additional positive and negative cable from the battery to the fuse block. So your battery will have two sets of cables coming from it, one set to the inverter and the other set to the fuse block.

You could also use busbars to connect everything up. If you go this route you only have one set of cables from the battery to the busbars, then one set of cables from the busbar to the inverter, and another set of cables from the busbars to your fuse block.

Using busbars isn't required for a simple system, it just makes a more tidy wiring layout.

Hope this helps!

This is very interesting...here's one scenario I've wondered about: What if I get my system up and running with some devices wired to the fuse box, and then later I realize I want to wire more devices to the fuse box...how do I "shut down" the system to add the new wiring? I work in IT and for example, if I was going to replace the memory on a computer, I'd need to power it off and unplug the power cable. For the fuse panel, would I need to just disconnect the 2 battery cables...or can appliances be added and removed from the fuse box with everything still wired up?

 

[Rednecktek]

Hi Rednecktek, thanks for the reply!

The 12v appliances are something else I was confused about.

I googled and found that some common 12v applliances are: Fridge, microwave, toaster coffeee maker ,kettle, blender, waffle maker, fans, lights.

Fridge, fans, and lights I have seen at 12v, but everything else on that list would require wires the size of jumper cables to power on 12v, so I think there's something wrong with your shopping list.

But what if I have, for example, a blender that plugs in with an AC cord...that would not be considered a 12v appliance right? Does "12v appliance" mainly refer to things in your camper that are hardwired such as the built in lights, water pump, water heater, etc ( aka not plugged in via AC?)

Yes, in an RV the lights, water pump, etc that are designed to run when you're NOT plugged into shore power are usually fed from some 12v batteries in the battery compartment or a box out on the tongue. If your camper can already power those items without being plugged into shore power or a generator then your camper has to have some sort of inverter mounted in it already.

I was looking at the cabinets in my camper and realized that the microwave just plugs into an AC outlet near the ceiling...so for the other things such as lights, would I need to disconnect the cables going into the existing camper fuse panel and re-wire them to my new solar fuse box?

If it's plugging into a regular 120v outlet then it's designed to run on 120v AC and you'd just leave it as that.

And on a separate note, what about making use of the existing AC electrical outlets already in the camper? Would that require disconnecting them from the existing fuse panel and reconnecting them to the fuse box of the new solar setup? Or since I'm going with the all in one MPP, is it better to just ignore the existing camper AC outlets and just use extension cords/power strips for AC devices that plug into the AC outlets on the MPP?

If your camper already has some kind of inverter built in then the MPP would be replacing it, so you would remove the old inverter and wire the MPP's AC-Out to wherever the existing inverter ties into your distribution panel.

However, if you've already got an existing inverter system it may be smarter to continue to use that to power your 120v stuff and just get a charge controller and panels installed to charge the battery.

I think at this point the question needs to go to: Do you already have an inverter installed in the camper or does your 120v stuff rely on being plugged into shore power?

This is very interesting...here's one scenario I've wondered about: What if I get my system up and running with some devices wired to the fuse box, and then later I realize I want to wire more devices to the fuse box...how do I "shut down" the system to add the new wiring? I work in IT and for example, if I was going to replace the memory on a computer, I'd need to power it off and unplug the power cable. For the fuse panel, would I need to just disconnect the 2 battery cables...or can appliances be added and removed from the fuse box with everything still wired up?

There are a couple options. You can either shut off the system with a breaker installed between the batteries and the fuse block which will down the entire 12v system OR just wire it up carefully and stick the fuse in last once the wires are connected. When you spec out your fuse block, get a version that has extra slots for future expansion, I.E if you need 7 circuits now, buy a 12 slot fuse block. It would wire up Batteries -> Breaker -> Fuse Block -> All The Things.

 

[Charleswgibbs]

This is very interesting...here's one scenario I've wondered about: What if I get my system up and running with some devices wired to the fuse box, and then later I realize I want to wire more devices to the fuse box...how do I "shut down" the system to add the new wiring? I work in IT and for example, if I was going to replace the memory on a computer, I'd need to power it off and unplug the power cable. For the fuse panel, would I need to just disconnect the 2 battery cables...or can appliances be added and removed from the fuse box with everything still wired up?

Ideally you would have some sort of disconnect, either a breaker or switch, between the battery and fuse block.

A breaker is nice as it also provides over current protection, if you don't have a breaker you'll need a fuse on the cables going to the fuse block. The current rating of the fuse/breaker required will depend on what size cabling you use, which is determined by how much power you plan to run through the fuse block.

Without a breaker or switch, assuming you have turned all the connected devices off, you could get away with just unbolting one of the cables.

Edit:

Whoops looks like redneck got here first, my post is a bit redundant now

 

[ianganderton]

Joe - have you done a power audit yet? It’s an important process and will help you understand your power needs

This is my sheet, it helped me understand what my needs were

Van CALCS

Power Audit Van Conversion -- Electrical loads Estimate Calculations based on 24 hr period. 1 - Electrical Loads: Inverter Item,Usage,Time (min),Wattage,Energy (W),Peak Amps,% of use,Ah,Notes Laptop,240V,1,275,45,206,4,15%,17 Toaster,240V,8,1000,0,83,0%,0,12 minutes is about 6 slices of toast so...

docs.google.com

Don’t buy any thing or start anything until you have got a good plan clear in your head. I’d recommend drawing out your own system diagrams and sharing them here.

Doing these 2 things (a power audit and planning your system) will save you a significant amount of cold hard cash plus make it more likely you will end up with a system that meats your needs

 

[ianganderton]

As far as laptop charging goes does your laptop have the ability to charge via usb—c pd? (The pd stands for power delivery)

If it does h then this could be an excellent solution if you have a 12V system

https://a.co/d/9yPPncm

In my van I decided to go 12V because most of the devices that run all the time are more efficient if run off 12V DC. I have a 2000W inverter but that is only needed for a short period of time at a time for high power loads. I can turn it off when I’m not using it

 

[JoeInNV]

I think at this point the question needs to go to: Do you already have an inverter installed in the camper or does your 120v stuff rely on being plugged into shore power?

I believe it needs shore power. It has this, would you consider this an inverter?

Home 3 - Progressive Dynamics

The Mighty Mini Compact All-In-One System offers an AC/DC Power Distribution Panel and Inteli-Power Converter with Charge Wizard battery charging technology.

www.progressivedyn.com

 

[Charleswgibbs]

I believe it needs shore power. It has this, would you consider this an inverter?

View attachment 116436

Home 3 - Progressive Dynamics

The Mighty Mini Compact All-In-One System offers an AC/DC Power Distribution Panel and Inteli-Power Converter with Charge Wizard battery charging technology.

www.progressivedyn.com

That's just a converter, it takes 120vac power and converts it to 12vdc for the lights etc, and also charges the onboard 12v battery. It wont convert battery power to ac output though.

Just to confirm, if you are not plugged into shore power, you are unable to use ac appliances, wall outlets, etc correct? They only work when plugged in? If so you probably don't have an inverter already.

How do you plug into shore power? Is it like a regular home extension cord, or a larger one like this?

https://www.lowes.com/pd/Champion-Power-Equipment/5013554661?cm_mmc=shp-_-c-_-prd-_-sol-_-ggl-_-PLA_SOL_240_Pressure-Washers-Generators-_-5013554661-_-online-_-0-_-0&ds_rl=1286981&gclid=CjwKCAjwtKmaBhBMEiwAyINuwAZVy1NfAUpde9Ty_54N7_pH3drDE6B7Sk7u_nKYdUcL5fXCtmKlBRoCb-MQAvD_BwE&gclsrc=aw.ds

I'm assuming there is also a breaker panel somewhere in the camper?

 

[JoeInNV]

That's just a converter, it takes 120vac power and converts it to 12vdc for the lights etc, and also charges the onboard 12v battery. It wont convert battery power to ac output though.

Just to confirm, if you are not plugged into shore power, you are unable to use ac appliances, wall outlets, etc correct? They only work when plugged in? If so you probably don't have an inverter already.

How do you plug into shore power? Is it like a regular home extension cord, or a larger one like this?

https://www.lowes.com/pd/Champion-Power-Equipment/5013554661?cm_mmc=shp-_-c-_-prd-_-sol-_-ggl-_-PLA_SOL_240_Pressure-Washers-Generators-_-5013554661-_-online-_-0-_-0&ds_rl=1286981&gclid=CjwKCAjwtKmaBhBMEiwAyINuwAZVy1NfAUpde9Ty_54N7_pH3drDE6B7Sk7u_nKYdUcL5fXCtmKlBRoCb-MQAvD_BwE&gclsrc=aw.ds

I'm assuming there is also a breaker panel somewhere in the camper?

This is what the shore cable looks like:

 

[JoeInNV]

I'm assuming there is also a breaker panel somewhere in the camper?

Is this what you mean?


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