array distance to controls

plongson
plongson Solar Expert Posts: 115 ✭✭
I'm planning for the optimal location to place a tracker array in my new off grid home. Because of trees and other shading obstructions, the best place would have approximately a 200' run. Is this too far? Can this be made to work with correct wire sizing? It is a 10 panel 185w each tracker.
THANKS! PAUL
3500w solar, 800AH with Rolls Surrette, Magnum inverter, Midnite charge controller, Kubota 21kW diesel genset...private well...and just recently connected to city power for additional options...nice to have options 
«1

Comments

  • rollandelliott
    rollandelliott Solar Expert Posts: 834 ✭✭
    Re: array distance to controls

    u need to figgure out voltage losses, what voltage are the panels? 18v probably?

    the higher the voltage the better for your system.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: array distance to controls

    Roland's right. 200' is quite a distance and you need to check some calculations. You can use this Voltage drop calculator: www.solar-guppy.com/forum/download/voltage_drop_calculator.zip

    Or one of the on-line ones like this at Powerstream: http://www.powerstream.com/Wire_Size.htm

    In all likelihood you'll need to run a fairly high Voltage array and an MPPT controller to handle it.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: array distance to controls

    With a "typical" Vmp-array of 100 volts maximum (depending on charge controller, temperature of site, etc.)... We aim at 1-3% maximum voltage drop. By the numbers and using a generic voltage drop calculator:
    • 1,850 watts / 100 volt Vmp-array = 18.5 amps
    • 3% * 100 volts = 3 volts maximum
    • 1% * 100 volts = 1 volt minimum (cost effective copper wire wise)
    • 200' one way, 18.5 amps, 3 volt drop, normal temps => 4 awg = 2.2 volt drop
    • 200' one way, 18.5 amps, 1 volt drop, normal temps => 1/0 awg = 0.9 volt drop
    Of course, this depends on the controllers and panels you pick... There are a few controllers that support higher voltages, and you have to look at the panel ratings and your local temperatures to figure out the maximum Vmp you can run for your setup.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: array distance to controls

    Combine at the panels as one string and use a midnite classic 250, you might get away with 10 gauge wire on the run.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Frxddy
    Frxddy Solar Expert Posts: 113 ✭✭✭✭
    Re: array distance to controls

    I am very new to solar and I am grid tied so when I see a question like this, I want to learn. I do understand electricity to s certain extent, but mostly "home power", that is, I have done little with DC.

    My first gut reaction to this is "Turn it to AC at the array and run AC the 200 feet.". Is there any particular reason that that idea isn't as feasible as I think? Of course it means building a shelter for the batteries, but if it makes everything have less loss, perhaps it's worth looking into?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: array distance to controls
    Frxddy wrote: »
    I am very new to solar and I am grid tied so when I see a question like this, I want to learn. I do understand electricity to s certain extent, but mostly "home power", that is, I have done little with DC.

    My first gut reaction to this is "Turn it to AC at the array and run AC the 200 feet.". Is there any particular reason that that idea isn't as feasible as I think? Of course it means building a shelter for the batteries, but if it makes everything have less loss, perhaps it's worth looking into?

    The answer is: it depends.

    In this case there are ten 185 Watt panels to work with, which means you could have an array of 350 Volts Vmp. The trick with any system is to have the longest runs on the highest Voltage. So yes, putting the whole install near the tracker in a shed and running 240 VAC to the house might be a solution. There can be problems having the controller and inverter remote, such as not being able to read the screen conveniently. Or there might be reasons for not having a shed out there.

    There usually are several solutions to one problem, so you have to play around with the numbers on the whole system design and consider all the possibilities to see which answer is best.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: array distance to controls

    More or less, it is the issue of monitoring and the setup (battery bank, charge controllers, inverters, etc.). Battery Monitors, Remote Inverter Interfaces, Remote Start for gensets, etc. all (usually) have distance limitations of 30-100' or so (10-30 meters). Longer distances becomes a game in itself to setup and operate your power system remotely.

    Yes, sending 120/240 VAC split phase is (usually) better than sending any other lower voltage (array or DC battery bank) the long distance.

    However, there are advantages when sending the solar pv longer distances (with MPPT controllers), is you can use smaller gauge wire (relatively) because there is no surge current (most "good" inverter support 2x surge current, and most induction motors will pull 5x current on startup, even electronics/filament bulbs/and other can have significant surge current--upwards of 45-50 amps for a few cycles on 120 VAC 15 Amp circuit).

    So--steady current, known voltage drop that can be predicted, and no issues with starting a well pump causing your DVR to reboot (etc.)--Usually make sending the (medium high) solar PV DC energy the longer distance (point to point).

    If you have multiple distributed loads (home, well pump, etc.)--Sometimes you have no choice--you put the panels where the sun is, place the batteries where the major loads are, and send 120/240 VAC to other points (barn, well pump, etc.).

    Placing the major component$ with some physical distance between them can save you money if something goes wrong. A fire in your battery bank does not take out your panels or genset. A fire in the generator shed does not take out the PV system, remote fuel supply, or home, etc.

    Plan for the worst, hope for the best--Words to live by.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: array distance to controls
    Frxddy wrote: »
    My first gut reaction to this is "Turn it to AC at the array and run AC the 200 feet.". Is there any particular reason that that idea isn't as feasible as I think?

    Very much the right kind of thinking for these problems, I have my system setup this way, though only 50' to my building, Other considerations are a reduced battery capacity with cold, so if you a heavy winter user this might be an issue.

    I think, the Midnite classic controllers are the only ones currently that will handle up to 250 volts DC, most are limited to 150 volts for off grid instalations.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • plongson
    plongson Solar Expert Posts: 115 ✭✭
    Re: array distance to controls

    Hey all, THANKS for the reply's!! Nothing is installed yet and actually the purchase is just days away, so there is stil time for "adjustments". The issue with the home site is...lots of trees that will shade the array, and I just hate to cut trees to provide for my green power. Not that I'm a "hugger", but just the way it is...LOL

    System will be 48vdc.

    These are the panels: 10 (ea.)
    Conegry 185's
    Vmp: 36.1 Volts
    Voc: 45.3 Volts
    Imp: 5.12 Amps
    Isc: 5.23 Amps
    Module Efficiency: 14.5%


    And the controller is:
    Xantrex 60 Amp MPPT Charge Controller 12-60 VDC.
    Includes temp sensor. Max input 150 VOC.

    Universal Tracking Mount, 168 Square Foot

    Xantrex XW4548 120/240 Sine Wave Inverter 4500 Watt
    48 VDC Battery System

    It sux that the best spot for the array is 200' feet away but I'll cut if I have to to get them in closer.

    Paul
    3500w solar, 800AH with Rolls Surrette, Magnum inverter, Midnite charge controller, Kubota 21kW diesel genset...private well...and just recently connected to city power for additional options...nice to have options 
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: array distance to controls

    Looks like you might want to reconsider your charge controller. If the distance between the array and the controller must be 200 feet, you're either going to need some very heavy wire (I came up with 4 AWG - may not be right) or else configure the array for two parallel strings of five in series and use a MidNite 200 controller.
  • plongson
    plongson Solar Expert Posts: 115 ✭✭
    Re: array distance to controls

    Man, this is getting more confusing as I go! :blush: This my calculations, feel free to slap me for being ignorant...

    Each panel= 24v 5a

    Each 2 panel series = 48v 5a

    Put 5 in parallel = 48v 25a

    How does this effect the controller selection (xantrax vs midnite200)??
    3500w solar, 800AH with Rolls Surrette, Magnum inverter, Midnite charge controller, Kubota 21kW diesel genset...private well...and just recently connected to city power for additional options...nice to have options 
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: array distance to controls
    plongson wrote: »
    Man, this is getting more confusing as I go! :blush: This my calculations, feel free to slap me for being ignorant...

    Each panel= 24v 5a

    Each 2 panel series = 48v 5a

    Put 5 in parallel = 48v 25a

    How does this effect the controller selection (xantrax vs midnite200)??

    Nope. Those are nominal Voltages. From your own previous post the panel specs are:
    Vmp: 36.1 Volts
    Voc: 45.3 Volts
    Imp: 5.12 Amps
    Isc: 5.23 Amps

    How does this work out? Not good because you're trying to run 200 feet of wire to carry the power.
    Voltage drop on that distance configured for 48 Volts @ 25 Amps and you need 1 AWG to keep the V-drop below 3%. Do you want to buy 400 feet of 1 AWG copper wire? Most of us aren't that wealthy.

    So the solution is to increase the array Voltage until a reasonable wire size is met. Unfortunately the Xantrex has a 150 Volt limit, which means it can't handle more than three of those panels in series before its maximum input Voltage (based on Voc) is reached. It gets worse if the temps go colder.

    And I meant to say the Classic 250, not 200. Five in series on that would be:
    Voc 226.5, Vmp 180.5, Imp 5.12 (two strings in parallel Imp 10.24).

    Much better to get the Voltage up and keep the current down.
  • plongson
    plongson Solar Expert Posts: 115 ✭✭
    Re: array distance to controls

    Thank You 'Coot...

    I really appreciate your help and patience, I'll get my head around this. So if I know my FLV (full line voltage) and I go by the prescribed loss tables, I should know how far I can run and what size conductor is recommended...Correct?
    3500w solar, 800AH with Rolls Surrette, Magnum inverter, Midnite charge controller, Kubota 21kW diesel genset...private well...and just recently connected to city power for additional options...nice to have options 
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: array distance to controls

    Take a look at this on-line V-drop calculator at Powerstream: http://www.powerstream.com/Wire_Size.htm
    (Bottom of the page; useful AWG chart above it.)

    You have to consider the Voltage, the length of run, the gauge of the wire, the type of wire, the Amps it's expected to carry ...

    No simple tables to follow, just a recommendation to try and keep losses below 3%

    You can do your own precise calculations with this V-drop tool created in large part by niel and currently hosted by the very knowledgeable Solar Guppy: www.solar-guppy.com/forum/download/voltage_drop_calculator.zip
  • solarvic
    solarvic Solar Expert Posts: 1,071 ✭✭✭✭
    Re: array distance to controls

    Why not get one if those new xantrex snieder 600 volt charge controlers and just run one string. The charge controler will cost more but you will probably be able to run #8 wire. maybe #10. I didn,t look it up yet but I am planning on running over 500 volt to a gti inverter at about 325 ft and can use #8 wire. :Dsolarvic:D
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: array distance to controls
    solarvic wrote: »
    Why not get one if those new xantrex snieder 600 volt charge controlers and just run one string. The charge controler will cost more but you will probably be able to run #8 wire. maybe #10. I didn,t look it up yet but I am planning on running over 500 volt to a gti inverter at about 325 ft and can use #8 wire. :Dsolarvic:D

    Because they cost $1300, not including the "extras". :roll:
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: array distance to controls

    The Midnite 250 CC may just do the trick. It is not possible for mere mortals to discover the location of the OP. But the Voc is a bit high for the CL 250 with strings of five panels, unless the location is in moderate winter climes.

    RE the Schneider MPPT 80 600, as Marc mentioned, it is a bit expensive. Seems to be about $1600 minimum if one already has the SCP.

    And, it is possible that a Vmp of 360 Volts is a bit low, I forget the Vin range for MPPT of the 80 600. It may be OK. The CL 250 may just work, and would be a lot le$$.

    Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: array distance to controls

    Atlanta, Georgia - Las Vegas, Nevada - Chantilly, Virginia - cold temps shouldn't be too much of a concern. :roll:
  • solarvic
    solarvic Solar Expert Posts: 1,071 ✭✭✭✭
    Re: array distance to controls
    Because they cost $1300, not including the "extras". :roll:
    I like advanced energy,s string chart as it will give you the voc. at highest temp and lowest temp. At 30F the voc is listed @ 48.2 which would work as long as it didn,t get any colder on the midnight 250. I checked the voltage drop programm that is on our host site and #8 should work at the low est VMP. http://www.windsun.com/Hardware/Voltage_Calc.htm
    I would like to have one of those new 600 volt controlers but I also think they are too expensive. Maybe the price might come down

    http://renewables.advanced-energy.com/StringCalculator.aspx#RESULTS First website for voltage drop and second is for advanced energy :Dsolarvic:D
  • Frxddy
    Frxddy Solar Expert Posts: 113 ✭✭✭✭
    Re: array distance to controls
    Because they cost $1300, not including the "extras". :roll:

    And how much is 400 feet of zero gauge? ;)


    I hadn't given batteries freezing a thought.

    I don't want to hijack this post..... but do want to say thanks for all the info! All good food for thought.
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: array distance to controls

    Someone else recently asked about how to handle a 200 foot run, here are my replies from that thread, with some minor editing:

    ...or build a small "power hut". I have a minimum 200 foot run, too, and have considered this. Get the PV voltage up and use the Midnight [charge controller], making a run 50-100 feet to a hut, then run the 240 AC the rest of the way. Basically cutting each run before voltage drop becomes an expensive problem to solve. Plus this keeps the equipment out of the house so an inverter fire doesn't wipe out the house (and a fire in the house doesn't leave you w/o a power supply to help rebuild it).

    If you use the 600 volt unit from Xantrex you could use fairly thin wire and run it all the way home, no hut, but that is a really dangerous voltage.
    Originally Posted by ggunn
    One thing to consider is voltage drop, which actually is voltage rise on the AC side at the inverter, since the voltage at the interconnect will be what it is. Inverters have a voltage range in which they operate, and if the voltage rises to that limit they will shut down. It may be better to take the voltage drop hit on the DC side.

    That is another reason for shortening the AC run by putting a hut in the middle somewhere, yes.

    200 volts DC over 200 feet requires 8 gauge to get the voltage drop below 5% @ 25 amps (roughly 5 kw array).

    Spliting this over 50 feet and 150 feet...

    200 volts DC over 50 feet theoretically is well below 5% using 14 gauge @ 25 amps, although I think code would require 12 gauge minimum.

    240 volts AC over 150 feet requires 10 gauge @ 20.8 amps to get below 5%.

    The cost difference between 50 feet of 12 gauge plus 150 feet of 10 gauge vs. 200 feet of 8 gauge probably won't offset the cost of building a hut but it might be close with today's copper prices...
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: array distance to controls

    Note that your array is smaller than the other one, so the minimum gauge wire needed for yours would be smaller. Except that I think the minimum gauge allowed is 12 (as I mentioned in my last post) so that's as small as you can go.

    No need for massive wire, or cutting trees.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    Re: array distance to controls

    I strongly agree with Bill's point about placing the solar equipment (inverters, charge controllers and batteries) in a separate structure away from the house and array.

    Either way, you are able to save one or the other. More work and expense but a cheap insurance policy. We had a serious National Forest fire up here this year and this planning decision made for a less stressful night.

    While we used an old 12' x 12' rock built storage building 60' or so from the house and 150' from the array, you can buy a pretty nice stick built 12' x 12' out of the box shed which can be installed in a day. Looks good and serves the purpose well.

    Our genset is on a pad next to the solar building but if it weren't built out of stone, we would have located it a little further from the solar mechanicals. However, our propane tank and line was set underground 250' from both the house and solar room.
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    Re: array distance to controls
    Mangas wrote: »
    I strongly agree with Bill's point about placing the solar equipment (inverters, charge controllers and batteries) in a separate structure away from the house and array.

    Either way, you are able to save one or the other. More work and expense but a cheap insurance policy. We had a serious National Forest fire up here this year and this planning decision made for a less stressful night.

    While we used an old 12' x 12' rock built storage building 60' or so from the house and 150' from the array, you can buy a pretty nice stick built 12' x 12' out of the box shed which can be installed in a day. Looks good and serves the purpose well.

    Our genset is on a pad next to the solar building but if it weren't built out of stone, we would have located it a little further from the solar mechanicals. However, our propane tank and line was set underground 250' from both the house and solar room.


    To be contrarian with my bud Mangas!. Or just some balance!
    The advantage for a fire threatened area is to have everything in one place. This allows one person to stay and protect the structure until an engine crew arrives.
    I did this for three hours last time. You can go further and make just one side of the structure the danger zone and have the other three sides safe enough to protect themselves. I am thinking a wood deck side that must be protected.

    The other disadvantage to me of having an outbuiding is there is some chance that some folks will not monitor things as well. Failures often give warnings in advance if one is there to notice. I try to design for an attached garage that has all the equipment for all systems there. An engineering space like on Star Trek. :roll: It works well in snow country and it gets looked at daily by default, I would hope!
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    Re: array distance to controls

    We just survived a 220,000 acre wildfire which burnt over 200 sections of desert mountain National Forest. Our ranch borders the burnt area and was surrounded by wildfire Mother's day night.

    The Incident Type 1 Team leader who fought the fire with us on the ranch told me the placement of our buildings and securing the solar mechanicals a short distance from the house was an important fire management measure.

    Far enough to separate the risk but close enough to protect both dwellings with the same equipment.

    I was there. Unbelievable with 30 foot flames surrounding the ranch house and flames 150+ feet plus over in the National Forest. They told us our fire prevention methods paid off.
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: array distance to controls

    For my 300' run from battery shed to pond pump, I used 6ga aluminum wire. You have to use proper precautions, anti-ox goop, and the right split bolts/terminals to make it safe, but it was better than copper.

    All in all, I pulled 980' of #6 alum, the other 680 went up the hill to power the ozone generator for the storage tank. That was 3, 1,000 foot spools I bought.

    over the creek and to the house, was #4 copper, for a 200' run. #2 aluminum was too fat to fit the conduit.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • plongson
    plongson Solar Expert Posts: 115 ✭✭
    Re: array distance to controls

    So how many solar controllers have burst in flame and burned homes down?? Is this a viable threat or chicken little syndrome?

    I know anything is possible but, we have gas water heaters, gas furnaces, stoves, ovens ,dang, some people still smoke in bed.

    So...is this a threat to seriously consider, or move on.

    We need a poll, How many who have designed their system have the whole package in their home vs in an outhouse???
    3500w solar, 800AH with Rolls Surrette, Magnum inverter, Midnite charge controller, Kubota 21kW diesel genset...private well...and just recently connected to city power for additional options...nice to have options 
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: array distance to controls

    Plongson;

    Don't panic! :D

    Solar electric equipment is just as safe as any other electronic device. Properly installed, it doesn't spontaneously combust.

    The thread has twisted a bit. The original suggestion of a separate power shed was for keeping the Voltage drop minimal: part way between the array and the house so that the losses are divided between the array to controller and the inverter to loads.

    Then we took the twist to looking at a separate shed being safer in case of fire (like the ever-present forest fire of B.C.!) you can protect a small shed of components more easily than a large building. Opinions differ on this, and you can see the logical arguments behind each POV.

    But the solar electric components aren't all that dangerous that they can't be safely housed within the residence. Mine are. I was just out there Saturday, working on the digester pump controls. The whole solar electric system was working perfectly, unattended for the past month. No worries.

    I do keep my gasoline and propane in a separate shed 50' away from everything else. That's as paranoid as I get. If a forest fire comes through, it won't really matter as they tend to wipe out everything in their path with frightening rapidity. :cry:
  • solarvic
    solarvic Solar Expert Posts: 1,071 ✭✭✭✭
    Re: array distance to controls

    If you use the 600 volt unit from Xantrex you could use fairly thin wire and run it all the way home, no hut, but that is a really dangerous voltage. Most of the GT inverters are either 500 vdc or 600vdc and are used all the time so having a 600 vdc charge controler shouldn,t be less safe. I will be using @12 wire to run my array over 350 ft to my 600 vdc gt inverter. :Dsolarvic:D
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: array distance to controls

    Regarding what is "unsafe"... My guess:
    1. Gasoline Generator
    2. Propane/Diesel Generator
    3. Battery Bank
    4. Battery Wiring / General Wiring
    5. Solar Array (UL/etc. rated)
    Part of why I was suggesting spreading things out was so you don't loose everything in one fell swoop (i.e., genset catches fire and takes out battery bank+solar array).

    Adding fuses/breakers where appropriate to prevent wiring from overheating if short circuited.

    A Battery Master disconnect would probably not be a bad idea either (pull chain to outside of shed--Break Glass and pull in case of smoke?). I have not seen many people do this in their home off grid systems--but this is common for buses, large computer installations, equipment, service stations and such (emergency power off switch).

    Others probably have better suggestions than I.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset