diy solar

diy solar

The quest to use my truck as a generator continues | chapter 2 | more power

Guda

Superstrut Strut
Joined
Nov 19, 2019
Messages
516
Just to catch everyone up. Generator burned down my most everything Jan 31st of this hellish year. Bought a "powerbox" to use my truck as a generator so I would not have to have a generator. Didn't work.

Now what I am doing is adding a 3000w Reliable brand inverter. I'm just making this is own system & leaving the under powered inverter in to do the light lifting. I am also adding a converter. I want to be able to pass power (even at bad conversion loss) back & forth from my truck system to my home system. Now while I am doin all this I am also going to hard wire the engine block heater to the low power side. Flip a switch vs dangling a extension cord.

Once I have my new home battery (ordering cells & BMS soon) I am going to add a Midnite 250 to the truck system. One or two pv on the truck roof & a trailer full of pv down the road. I am also looking at adding a 2nd 250amp alternator if the one I have is not keeping up. One last upgrade is going to be 2 more batteries that are jumbo to replace the trucks batteries.

I just got the inverter in the mail today. Have to open the "powerbox" tomorrow & make a parts list. I think I need a huge fuse. What size fuse for 12v 3000w inverter?

Oh also need to add hour meter to the truck for the biggest reason I want to do all this. Oil change. I really really disliked changing oil all the time. I'm not a oil guy, well unless its coconut oil in my hair or olive oil in my food, other than that, not into oil. Any solvents really are time to bust out the rubber gloves. :)
 
Is a Midnite 250 really necessary? The 250 handles less power than the 200 and 150. Only reason for 250 is if you plan to go crazy high with string voltage, which isn't necessarily the best by default.

3000W/12V * 1.25 = 312.5A
 
Is a Midnite 250 really necessary? The 250 handles less power than the 200 and 150. Only reason for 250 is if you plan to go crazy high with string voltage, which isn't necessarily the best by default.
I already own it. But ya thats kinda weird how the 250 only does 60a but the 150 does 90a. Its was only $450.
 
i use my van as a small generator.i have 400 watts pv on roof,200ah lifepo4 and a 1500 watt sine wave inverter.a 220 amp alternator all wired up to my renogy DCC50S.works great so far.all in a 2006 e250 van.

 
i use my van as a small generator.i have 400 watts pv on roof,200ah lifepo4 and a 1500 watt sine wave inverter.a 220 amp alternator all wired up to my renogy DCC50S.works great so far.all in a 2006 e250 van.

Nice!

Do you have a regular battery in the van also or does the van use the lifepo4?
 
When I built my 1st system the guy who sold me everything said to make sure the wire was same length between batteries. But in my truck I have 3 batteries all different distance from each other. Does not seam to be a issue.

I got the box open. They didn't fuse the inverter. I am going to add a fuse to the inverter I am adding.

I have a extension cord that should handle 20a. I wanted it on a cord reel but they are super spendy for hi amp wire. I've got to get a cord reel to put in the truck to plug in the truck. Need some sort of weather proof pass through for the cord.

The truck has 2 things to plug into AC. Block heater & a converter. Think I'll just power the converter & run the block heater off the 2000w inverter. Block heater is about 1000w so it shouldn't be too much even with the converter. Although I don't know the draw of the converter yet.

Also trying to decide if I want to use distribution blocks or just wire everything to the back of the inverter. Already have to wait to get a fuse shipped.
 
In a truck, it probably doesn't matter much. 12V loads are predominantly powered by the alternator, and the batteries don't do a lot (in normal truck-like operations).

The importance of "same length" wires is to ensure that all batteries in the bank see the same circuit resistance. If they don't, they will not share charge current and loads evenly. This leads to uneven wear and life of batteries and can lead to a battery being subjected to more current or discharge than its rating.

See the "Wiring" resource in link #2 in my sig. It discusses how to optimally wire batteries into banks as well as many other wiring topics.
 
The importance of "same length" wires is to ensure that all batteries in the bank see the same circuit resistance. If they don't, they will not share charge current and loads evenly. This leads to uneven wear and life of batteries and can lead to a battery being subjected to more current or discharge than its rating.
2 of the batteries are the trucks under the hood. The other one is in the back in a tool box. The battery in the back has some wiring that only allows it to charge once the trucks system reaches some voltage threshold. If I add a battery in the back, I'd need to make sure those connections are the same length. Gotcha!
See the "Wiring" resource in link #2 in my sig. It discusses how to optimally wire batteries into banks as well as many other wiring topics.
Awesome!
 
If you add another battery in the back, I'd just parallel it to the other one using short beefy cables, so the "back" battery bank behaves like one big battery.
 
Got the box pulled apart & my design contemplated. This 2000w inverter has no fuse. I can have 2 inverters on 1 fuse as long as both inverters are not on at the same time? Got my 400a fuse/holder ordered. I get wire & lugs from Napa auto parts. Seams like car audio is a good place to get stuff like distribution blocks & wire in a pinch. I need like a 2" rubber grommet to put through the metal lid & 3/4 ply. Or some sort of flush mount conduit I am unaware of. In town parts haul today, hopefully I'll find it all. I wish I'd remembered to order a fuse WITH the inverter. I can get everything but the fuse wired up & built out tho. My design does not bury the fuse.
 
When I built my 1st system the guy who sold me everything said to make sure the wire was same length between batteries. But in my truck I have 3 batteries all different distance from each other. Does not seam to be a issue.
I consider this doc the gold standard of explaining wiring in parallel batteries. It's more than just wire length. If you like math to back up explanations, it has it.

SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

As soon as I figure out signature blocks, I'm putting this in.
 
SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank
Thats awesome! Hopefully I'll be using that soon to figure out how to build my 16 cell 48v battery for my house.

I don't think I am going to be able to fit another battery in the truck box. By the time I pack in an inverter, converter SCC, cord reel & wiring. Not much room left. If I need more power I'll add a alternator & possibly beef up the trucks batteries.
 
Double up the awg wires, and you drop about 3awg, so 2X 8awg is 5awg.

"Reliable" is "WZRELB" - they're cheap Chinese inverters. They don't want to supply the proper wiring as that would increase the cost (4/0 ain't cheap, eh?"), but they seem like heroes to those that don't know better by supplying something that enables a connection to be made and the unit to work... just not to 3kW. 5awg won't fuse until about 800A, but it will get damn hot.
 
Double up the awg wires, and you drop about 3awg, so 2X 8awg is 5awg.
I see

"Reliable" is "WZRELB" - they're cheap Chinese inverters
I watched a lot of videos test the heck outta it & it passed with flying colors each time. Inexpensive yes, cheap no. But, I am probably now going to eat my words :( Back of a truck that drives off road every time it drives. I did buy rubber feet for it tho.

(4/0 ain't cheap, eh?"
Ug you can say that again. I didn't have enough $ in paypal to get everything on eBay. Napa only had 4/0 awg in black. Not a huge deal but I like my different colors. 6' was $85 & they didn't have the lugs I need either.

I'm like a week into Jan before all the stuff I need will be in. I wish I had thought it through better. Although, ordering everything all at once can lead to the wrong stuff. Like lug holes size.
5awg won't fuse until about 800A, but it will get damn hot.
Thats got me thinking about the wires that come from the truck to the box. They are 4 awg (I think). How will they handle enough power to supply the battery? I guess its normal for the charging side wire to be a lot smaller than the inverter wires. Some things I just chalk up to magic. Electricity is very magical. And fancy
 
Thats got me thinking about the wires that come from the truck to the box. They are 4 awg (I think). How will they handle enough power to supply the battery? I guess its normal for the charging side wire to be a lot smaller than the inverter wires.
How large are your chargers (in amps)?
Normally at least for mobile systems the inverter is sized larger than the charging system so wires can be smaller (sized appropriately to the max current of the charger).
Some things I just chalk up to magic. Electricity is very magical. And fancy
Seems that way sometimes doesn't it ?
 
I see


I watched a lot of videos test the heck outta it & it passed with flying colors each time. Inexpensive yes, cheap no. But, I am probably now going to eat my words :( Back of a truck that drives off road every time it drives. I did buy rubber feet for it tho.

It's not bad. It's cheap. I've mentioned I have the 24V/2000W version. It served me fine for the limited # of hours I needed it, and it sits waiting to act as my backup system if the Victrons ever take a dump. Just remember they have no meaningful surge that can last beyond a couple of Hz of the 60Hz AC wave.

Ug you can say that again. I didn't have enough $ in paypal to get everything on eBay. Napa only had 4/0 awg in black. Not a huge deal but I like my different colors. 6' was $85 & they didn't have the lugs I need either.

Yah... that's why they supply cheap stuff in its place. At least you can test it and likely get away with brief operation to moderate currents. it depends on the insulation rating. Some are up to 200°C meaning they can take well above what is typical of 90 or 105°C wire.

I'm like a week into Jan before all the stuff I need will be in. I wish I had thought it through better. Although, ordering everything all at once can lead to the wrong stuff. Like lug holes size.

I feel yer pain. I'm 25 miles from the nearest meaningful town, and specialty items like quality crimp lugs are not on the menu. I had to delay the installation of my BMV-702 a few weeks (next visit) because I didn't have big enough lugs as they were the largest of anything in the system.

Thats got me thinking about the wires that come from the truck to the box. They are 4 awg (I think). How will they handle enough power to supply the battery? I guess its normal for the charging side wire to be a lot smaller than the inverter wires. Some things I just chalk up to magic. Electricity is very magical. And fancy

How large are your chargers (in amps)?
Normally at least for mobile systems the inverter is sized larger than the charging system so wires can be smaller (sized appropriately to the max current of the charger).

Seems that way sometimes doesn't it ?

Just depends on the current coming from the chassis batteries. Are they going to complement the inverter power? If so, they're going to have a pretty notable voltage drop.

If it's just for charging, it's probably fine.
 
Just depends on the current coming from the chassis batteries. Are they going to complement the inverter power? If so, they're going to have a pretty notable voltage drop.

If it's just for charging, it's probably fine.
I skimmed this post and only vaguely recall details from the last post so I may be missing some context but from this statement:
Once I have my new home battery (ordering cells & BMS soon)
I am assuming the auxiliary battery bank is lithium, in which case it would need some sort of current limiting device between the vehicle system and the auxiliary system right?
 
How large are your chargers (in amps)?
Normally at least for mobile systems the inverter is sized larger than the charging system so wires can be smaller (sized appropriately to the max current of the charger).
The alternator put out 250amps. Unverified.
It's not bad. It's cheap. I've mentioned I have the 24V/2000W version. It served me fine for the limited # of hours I needed it, and it sits waiting to act as my backup system if the Victrons ever take a dump. Just remember they have no meaningful surge that can last beyond a couple of Hz of the 60Hz AC wave.
Cool
Are they going to complement the inverter power?
We will see if they are needed.
I am assuming the auxiliary battery bank is lithium, in which case it would need some sort of current limiting device between the vehicle system and the auxiliary system right?
Truck is agm. House is Lifepo4.
 
Back
Top