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beachman
Member
# Posted: 13 Jun 2014 10:30
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What about grounding a solar system? I am about to set up a more robust system with a PV away from the cabin and since we have some pretty good lightning storms, I plan to have a ground near the pv. I also will wire the cabin and have a ground there for the system - but I hear you have to tie both grounds together for some reason - equalization of a major strike or something like that. Anybody have thoughts on this?

MtnDon
Member
# Posted: 13 Jun 2014 12:02
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Distance from PV to CC and the other stuff??

What's the system voltage?

beachman
Member
# Posted: 13 Jun 2014 16:37
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Don, I have a 240 watt panel that I will run about 40 ft of 12AWG to a Morningstar charge controller, then on to a bank of 2 6volt deep cycle batteries (Trojan) in parallel to produce 12 volts, then to a 1000 watt inverter, to a distribution box to outlets and a couple of lights. I am concerned about the panel being exposed to potential lightning strikes being on the shore of a lake. The cabin system should be grounded for safety as well. I have a special lightning breaker to put in between the panel and the batteries. I think I can use the ground near the panel for the cabin and get away with one.

MtnDon
Member
# Posted: 13 Jun 2014 18:36
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Two good references for the topic

One at NAWS

and another

The best surge protector / lightning arrestor is the one from Midnite Solar. It has an LED that indicates if it is working properly. The others only let you know they have failed when the system electronics get fried.


With the PV panel close enough to the CC and other stuff you should run a ground wire along with the positive and negative from PV to CC. That ground would be connected to a ground buss at the cabin. The buss would be grounded to a pair of ground rods, usually 8 foot copper clad steel. Separate the rods by 8 feet minimum and connect to the ground buss with a continuous wire from buss to the first and then on to the second rod. Not 2 separate wires.

Your inverter may or may not have an internal bond (AC neutral connected to ground). That will have to be checked before making any bonds in the AC servoce panel, if you use one.

beachman
Member
# Posted: 13 Jun 2014 21:08
Reply 


OK Thanks. I think I follow you here. It seems to make sense and the use of a bus is a good idea. One thing I was planning is the use of a ground plate near the pv. The ground is rocky and driving a pole of sufficient length would not be possible. if I did get a strike, the distance to the plate would be shorter - and away from the cabin. Then I was going to run a ground wire from this plate to the cabin instead of having a ground at the cabin.

MtnDon
Member
# Posted: 13 Jun 2014 22:09
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Ground rods can be driven at an angle too; don't have to be straight down. More important than straight down 8 feet is to hopefully have the grounding rod in moist earth. If you are thinking of a steel plate, they rust and the rust doesn't conduct electricity as well. A stainless steel plate might be better if you can't do copper.

Two separated ground rods are recommended.

One advantage of a buss is that any one item can be removed for service without interrupting the ground path as can happen when wires are connected serially from one thing to another.

beachman
Member
# Posted: 16 Jun 2014 09:26
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Here is my proposed system. Anything anybody might recommend or warn against?
solar plans
solar plans


MtnDon
Member
# Posted: 16 Jun 2014 09:49
Reply 


Maybe just the fault of the drawing detail, but a lightning arrestor has three wires. One connected to positive, one to negative and one to the ground wire.


Batteries; two six volt would be in series not parallel as labeled.


The inverter size is not listed, nor the distance between it and the batteries. Twelve gauge wire does seem light, but then there is a 20 amp fuse listed so maybe that is just a small inverter. 20 amps on 12 volts should have the distance no more than 4 1/2 feet and even that will have 3% voltage drop. I'd use heavier gauge wire myself; like at least 8 gauge and keep the line drop as close to 1% as possible.


Can't comment on the 12 gauge for the PV as distance, amps, volts are unknown.


Fuses. Add fuses in the + from PV to CC and CC to batteries. Also a fuse for the 12 vdc water pump.


Small buss bars at the batteries can also make those connections tidier as well as make it possible to add remove connections for devices without disturbing the others. Just a thought I find useful.

ILFE
Member
# Posted: 16 Jun 2014 11:11 - Edited by: ILFE
Reply 


beachman,

Here are two schematics of the new Kid MPPT Controller by Midnite Solar, as PDF files. One shows a parallel PV array; the other in series. They show proper order of fuses, wiring for the lightening / surge protector, batteries, etc.

I have one of my array schematics attached as well. I have no lightening protection currently attached to it. As soon as my Kid controller arrives this month, I will be replacing the ProStar 30m with it.

Hope this helps,
Kid_12V_2p_Par_DN.pd.pdfAttached file: Parallel Schematic
 
Kid_12V_2p_Series_DN.pdfAttached file: Series Schematic
 
400 Watts Array
400 Watts Array


MtnDon
Member
# Posted: 16 Jun 2014 12:31
Reply 


Quoting: ILFE
no lightening protection



Just an opinion, but the lightning protection should be installed first thing. I have personal knowledge of 2 different systems being struck by lightning and all the electronics getting fried. Only the PV panels remained functional. One had no protection and the other had a brand that had been unknowingly struck before and rendered inoperative. That is why I do heartily recommend the Midnite Solar aresstors / surge protectors for the reason mentioned before, the LED.

For certain there are many unprotected systems that never get struck; some folks can be luckier than others.

ILFE
Member
# Posted: 16 Jun 2014 15:57 - Edited by: ILFE
Reply 


MtnDon,

I am not sure if it matters really, geographically speaking. But, I live in Cambodia. We get tons of rain every year - and brother, I mean TONS. But, the numbers of lightening / electrical storms we experience only rarely happen. (No, I am not discounting the fact that it only takes one strike to completely trash an entire solar system.)

But, one also has to take in consideration what most people can afford, especially in this country. Most Khmers (who even can afford a solar system) only have the funds to pay for a fairly simple, small output system to be installed on their homes. I'm pretty certain that lightening protection is quite low on the priority list, here in the Kingdom, especially for poor rice farmers.

From the time I began looking for a local company to provide the parts we needed to construct our system, until now - eight months later, I have yet to find a local company that even offers lightening / surge protection devices in stock.

Now, my personal opinion. For me, it isn't a very high priority. Especially for a small system like ours, I really don't see it being necessary. Not to mention, is there any guarantee, whatsoever, that adding lightening protection even be able to do its job and protect your system from a bolt? Not on your life. I too, have personally seen what lightening can do to people, property, farm animals, homes, and even amateur radio equipment - which was well protected. I have yet to see a device on this planet that I feel would truly protect any solar array from a lightening strike.

For me, high priority is to get the power generated where it is needed.

beachman
Member
# Posted: 16 Jun 2014 17:43
Reply 


Thanks to you both. Yes, series would be correct. Each schematic seems to show a common ground so my plans should be OK. I agree about the lightning arrester and I plan to get this installed as well as the grounding prior to hooking up the panels. I'm thinking about the ground rods going in at an angle - might try this. The place is quite rocky and an electrician told me to use the grounding panel and to put it down 2 ft. I see where the breakers in the Kidd schematics isolate the system so it can be shut down. Obviously I am no electrician and YouTube gives enough info to be dangerous. I will likely get a professional opinion before I go live. My place is so remote that I have had to learn all of this myself over time. Thanks so much for your comments.

creeky
Member
# Posted: 16 Jun 2014 19:59
Reply 


beachman. your electrician is correct. plate grounding is code acceptable. 2 ft by code. the plates are galvanized metal. given these factors, you wouldn't expect there's much chance of them rusting.

ShiaX
Member
# Posted: 22 Apr 2024 15:14
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I am trying to figure out if a EG4-WALLMOUNT INDOOR BATTERY 280AH 51.2V 14.3KWH & EG4 6000XP OFF GRID INVERTER BUNDLE 8000W PV INPUT 6000W OUTPUT ALL IN ONE SOLAR INVERTER will be a big enough system to power my whole off grid 600 sq ft cabin? Also how many solar panels would I need to have for this system?

ShiaX
Member
# Posted: 22 Apr 2024 15:16
Reply 


Is a 6000 watt output solar system big enough to run my 600 sq ft off grid home full time? Or would I need to go up to a 12000 watt output solar system?

Steve_S
Member
# Posted: 22 Apr 2024 16:23
Reply 


ShiaX, his is a Necro Post - old as the hills.
No one here is using any EG4 gear but a lot of our members at DIYSolarForum do & the vendors are also on there. https://diysolarforum.com/

Your 48V/280AH battery pack with 14.3kWh is quite respectable for a small place. The kicker is Location because solar charging varies so much.

I live in a 500Sq Foot cabi with all the normal & usual residential goodies.

My system uses a 4000W Samlex Inverter/Charger that outputs 120VAC/33A but can handle up to 120V/45A Surge. This operates my home, including deep well pump, radiant heating systems, lights & all. I am 100% OFF GRID, rural & Remote near Algonquin Park Ontario Canada. Up until now I have been using:
- 1 Solar Array of 2080W Solar Array attached to a Midnite Solar Classic-200 Solar Controller providing 79A charge.
Within a couple of weeks, I am adding a 2nd Solar Array of 2370W attached to a Midnite Classic 150 to provide 94A charging.

4450W will provide 173A charging current to my battery bank.

Because I am rural, remote and am subject to nasty winters etc my Battery Bank is setup to provide 10 days power. It is 1680AH / 43kWh LFP.

NOTES TO CONSIDER
Conservation & efficiency (appliances/devices) rules. It is far cheaper to conserve energy than to generate & store it. Granny's fridge that you inherited is likely a monster power pig.

AIO's (All-In-Ones) are not super efficient (unless it is a Tier-1 product $$$) but they are very convenient, they usually take a larger array or set of arrays but you will need to look at the specs of your particular model and maybe even talk to your vendor... The guy's at Signature Solar USA actually came up with the EG4's and worked with the Chinese OEMs to make them happen, now several vendors are offering them.

https://signaturesolar.com/

ShiaX
Member
# Posted: 22 Apr 2024 17:54
Reply 


That all just sounded like a foreign language to me lol. I know absolutely nothing about solar. Pretty much I'm trying to find out how big of a system I'm going to need to power my 600 sq ft Arizona off grid home. Regardless of the brand system, I'm trying to figure out is a 6000w output system big enough or will I need to go up to 12000w system.

gcrank1
Member
# Posted: 22 Apr 2024 18:30
Reply 


You MUST do an energy audit!
How, you ask?
Go to Diysolarforum as Steve suggests and find out, It Is All There.

ShiaX
Member
# Posted: 22 Apr 2024 18:37
Reply 


I've went there already, the issue I'm having is I don't have any current usage. I am a long haul over the road truck driver so I do not have a daily monthly or hell even hourly usage rate to audit. Every time I reach out to different companies thats all they want to talk about in order to build a system and I understand why. However I don't have a power bill to get a usage rate. The only power I use as of now is to charge my phone and laptop in my truck lol. I will be building on rual bare land and having to purchase all appliances ect.

razmichael
Member
# Posted: 23 Apr 2024 07:46 - Edited by: razmichael
Reply 


No one can tell you what size system you need until you can say what you want to run. An energy audit can be done in advance by listing your 'must haves' and 'nice to have' thing then doing some research on options for each including price and functionality and power draws. You want an electric fridge or propane? What do you want to cook on? How many lights are needed and for how long - what luxuries are you willing to do without - and on and on. As Steve stated, "Conservation & efficiency (appliances/devices) rules" but this also depends on your budget.

Alternatively, pick a system and then plan around that but be ready for the potential to need to limit your choices later on. Your actually in a good position as you can sort this out before you commit. Additionally you can think about making sure whatever you get is modular, in that you can easily expand (rather than replace).

Again, everyone is telling you the same basic thing - unless you figure out how much power you want to use (in your case as you are in the planning stage), no one can tell you what size system you need.

Steve_S
Member
# Posted: 23 Apr 2024 07:59
Reply 


Raz & Others, Shia's posted on DIY and provided much more information. Will be building a NEW place around 600 square feet in Arizona. Appliances etc will be bought, nothing old going to the new build.

This is Shia's thread over there for those interested in following it.
https://diysolarforum.com/threads/help-with-building-an-eg4-full-time-off-grid-solar- system-for-a-600-sq-ft-home.82785/

matthewwolf
Member
# Posted: 17 May 2024 17:49
Reply 


Quoting: ShiaX
Is a 6000 watt output solar system big enough to run my 600 sq ft off grid home full time? Or would I need to go up to a 12000 watt output solar system?


The size of the solar system you need really depends on how much juice you're using.
For your 600 sq ft off-grid place in Arizona, a 6000 watt system might do the trick if you’re keeping things light and using energy-efficient appliances. But if you're a power user, you might wanna think about a bigger setup, like a 12000 watt system, especially to cover cloudy days or times when you're using more power. https://www.eia.gov/todayinenergy/detail.php?id=46276

Plus, Arizona’s got some sweet state incentives for solar power that can make it a lot cheaper to go big. These deals can cut down the upfront costs and make your solar investment really pay off. You can check this out for more info: https://arizona.statesolar.org/

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