solar instulation

[RonMar]

Ron
I have been an electrician for over 30 years in that case you propose then any large parallel wire runs would have to have each wire protected individually!

No. That would be parallels from a single source to a single load if I understand you correctly, like multiple strands of a stranded cable, each carries a part of the load, but they are already shorted so that won't get any worse, and if a strand opens, the rest just carry more current.

It is common practice to parallel wires and have them on one large over current device as we wouldn't be able to work with the wires that large the NEC has provisions to cover that type of insulation.

Again you just described stranded cable with a single source feeding a single load. The shorting(they are already a low resistance conductor) or opening of any one will have very little efect on the overall result. none of them have the potential to either supply or become a load all by themselvs. Would you work on any one of these individual power lines with out securing the single source of power(or isolating it from the others)?

A better analogy would be the output of several electric generators in parallel feeding a common load. Have you ever seen an electrical generation source that didn't have a cutout or circuit interruption device on it's output? A short in one generator turns it from a generator to an electrical load without an interrupter to protect it and isolate it from the other sources.

You have made four independent 12V, high current power sources and wired them in parallel with no individual isolation or protection. Each one of these four high current power supplies has the potential to become an electrical load(fed by the remaining power sources) either by accident or of it's own accord thru an internal battery failure.

I have been herding electrons for a living for 24 years now(it was a hobby long before that). I just wouldn't feel right not letting you know about what I see as a potentially serious problem based on that training and experience.

Best of luck to you Tom

 

[ctpres]

I am NOT recommending this co. That's why I didn't mention name The Citizenrē Corporation

 

[tommu56]

Rob

The mountin in the view is about 1700 yards away. One of the other cabins long range hunt off my porch and shoot to that mountin.

They use a 300 wetherbee necked down to 7mm in a 2" bull barrel with an externally adjusted scope the thake one shot off target for windage dial that in and pick the deer off with the second
you can actually see the bullit traveling through the air its amazing.

But the game commision around here is controling the heard for the wood lot production in my opinion they issue too many doe lisenses so I havent hunted in about 5 or 6 years.

tom

 

[MikeD74T]

New co. here in TX may hit it big in solar. They will install enough solar on you roof to generate excess during the day which they sell to grid. At nite you run on grid. No batteries. $500 deposit refunded with interest at end of term (1 to 20 yrs). NO INSTALLATION charge and they gurantee you current electric rate for the term of agreement. They expect to make enough money on excess generated during day to cover your use at nite and show a profit. They could end up with a massive solar field and no land cost. Plant yet to be built so it is to early to know if this is ever even going get off ground

One of my coworkers is the fire chief in a neighboring town. They're building a new fire station. He's been hounded by companies looking to sell solar installations, all predicting quick payback & energy independance. I suggested he lease them roof space & buy power from them - he's had no takers so far. My employer is , I think, the biggest solar producer in the US. It's all for energy credits, our real money comes from nuclear. Be interesting to see how your situation works out. MikeD74T
PS I'm certainly not anti-solar, I just don't think photovotaic is self sustaining yet.

 

[hitekcountry]

NEC allows Parallel wires without overcurrent protection on each wire that is correct. But in the case of parallel electrical sources each source shall have its overcurrent device.

NEC 705.30 ".....Equipment and conductors connected to more than one electrical source shall have a sufficient number of overcurrent devices located so as to provide protection from all sources."

 

[tommu56]

hitekcountry

Sec. 705.30--Overcurrent Protection for Circuits and Equipment in Interconnected Electric Power Production Sources

I don't think a battery bank is an interconnected source.

I am looking for a fuse to put in line with the positive cable to protect equipment inside.
All the ones I have found so far are jury rigged type t fuse in a pvc condulet that says it needs t be in metal enclosure.

tom

 

[hitekcountry]

I don't think a battery bank is an interconnected source.

tom

What You have are 4 12V interconnected sources.

 

[cityfarma]

Nice pictures. That's a lot of battery for only 250w of solar panel. How many amp hour is your battery bank? Are you going to add more panels soon?

You think that ratio is bad! I have approx 2500 AHr @ 12v with 60W in panels! The company I work for was replacing the UPS batteries so I loaded up the trailer with 6v 100Ahr SLA batteries and took them to my place down south. I had to split them between two caravans but as one bank. I only get there every two weeks for a couple of days and have not yet run out of power I use a 600VA el cheapo inverter to run my TV and laptop.

Cityfarma

 

[cityfarma]

I have since read more of this thread and before anyone asks, I have a couple of banks of series parallel batteries. Each bank is protected by a fuse where they become one bank but individual strings do not have fuses. To join in the two banks from each caravan, I have welding cable with a fuse on each end to protect the banks in the event of a short. This would probably not meet your regulations but works for me. If I had a house, I certainly would set things up differently.

You may also be concerned about the batteries being inside the caravan. Because the supply panels are small, there is no gassing in the SLA batteries. The van is also very old and drafty so has very little chance of building up any gas.

I am building a garage for the tractor and may move the battery bank to the garage and start again with fuses in each string.

Cityfarma

 

[stumpfield]

You think that ratio is bad! I have approx 2500 AHr @ 12v with 60W in panels! The company I work for was replacing the UPS batteries so I loaded up the trailer with 6v 100Ahr SLA batteries and took them to my place down south. I had to split them between two caravans but as one bank. I only get there every two weeks for a couple of days and have not yet run out of power I use a 600VA el cheapo inverter to run my TV and laptop.

Cityfarma

You must got really really good batteries. Who made those batteries? For typical lead-acid batteries, the self-discharge rate is greater your panels can produce.