Advice on this system and can an MC4 connector connect directly to a circuit breaker?
GreenGen XVIII
Registered Users Posts: 15 ✭
Hello everyone!
I'm a newcomer to the forum and solar power in general and so far this forum has been a treasure chest of information for me, which i highly appreciate. However, I would like to know if an MC4 connector, male or female, can connect directly to a DC circuit breaker?
I'm planning to construct a system with 8 100W panels connected in parallel running to an Outback Flexmax 80 FM80 MPPT 80 AMP Solar Charge Controller, which feeds a
Power Bright PW6000-12 6000 Watt Power Inverter...i've found an article showing how to construct your own solar combiner box, what amperage should the circuit breakers be and any thoughts and advice on that system? I'll upload drawn schematics to the thread shortly
I'm a newcomer to the forum and solar power in general and so far this forum has been a treasure chest of information for me, which i highly appreciate. However, I would like to know if an MC4 connector, male or female, can connect directly to a DC circuit breaker?
I'm planning to construct a system with 8 100W panels connected in parallel running to an Outback Flexmax 80 FM80 MPPT 80 AMP Solar Charge Controller, which feeds a
Power Bright PW6000-12 6000 Watt Power Inverter...i've found an article showing how to construct your own solar combiner box, what amperage should the circuit breakers be and any thoughts and advice on that system? I'll upload drawn schematics to the thread shortly
Comments
-
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
Do you have any idea how big a wire you will need to get 6000 watts @ 12 volts, that is 500 amps without any surge figured in. WOW! -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
This should give you an ideal of the mc-4 connecting. I don't remember for sure so wait for some one else to answer but I believe you times your amps by 1.56 and that is the size breaker you use. The back of the panel should tell you the max breaker you can use if you put the panels in series.
Here is the link for ideals.
http://www.solar-electric.com/installation-parts-and-equipment/midnite/pvarco/prpvcobo/misomnsoarco5.html
Good luck
gww -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breakerGreenGen XVIII wrote: »Hello everyone!
I'm a newcomer to the forum and solar power in general and so far this forum has been a treasure chest of information for me, which i highly appreciate. However, I would like to know if an MC4 connector, male or female, can connect directly to a DC circuit breaker?
I'm planning to construct a system with 8 100W panels connected in parallel running to an Outback Flexmax 80 FM80 MPPT 80 AMP Solar Charge Controller, which feeds a
Power Bright PW6000-12 6000 Watt Power Inverter...i've found an article showing how to construct your own solar combiner box, what amperage should the circuit breakers be and any thoughts and advice on that system? I'll upload drawn schematics to the thread shortly
Welcome to the forum.
We need to do some clarification here.
First, as solar_dave said a 6kW 12 Volt inverter will draw an enormous amount of current. In short form, it's a piece of junk. Get rid of it if you seriously need that kind of power. You should have a 48 Volt system if you need that level of output.
Second, a charge controller does not feed an inverter. Off-grid inverters run from batteries. Charge controllers recharge the batteries. It is important to keep the ideas separate.
Third, an MC4 connector is designed to go between another MC4 connector and a piece of wire. There is no way the wire end will attach directly to a circuit breaker. Or perhaps I should say "no safe way" as so many people are intent on doing things wrong. Often because they saw some idiot put up a Youtube video about it.
Fourth, 800 Watts of PV as four 100 Watt panels on an MPPT controller: unless you already have the panels there are cheaper options to get that much power from an array with fewer panels. As it is you could put the panels in strings of two each and have four strings. Most sensible way to combine the four strings is wit a MidNite combiner box. It may not cost less than your DIY box, but it's guaranteed to be built right. At least take a look at their design; the MC4 connectors are built-in to the box.
Fifth, the panels will have a maximum series fuse rating on them. This is the most current they can handle as a conductor if something goes wrong. It is usually, but not always, 15 Amps. That is the size of individual string breakers you would use.
Finally, remember you will also need fuse/breaker on the output of the charge controller to the batteries and another on the wire from the batteries to the inverter. -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breakerCariboocoot wrote: »Welcome to the forum.
We need to do some clarification here.
First, as solar_dave said a 6kW 12 Volt inverter will draw an enormous amount of current. In short form, it's a piece of junk. Get rid of it if you seriously need that kind of power. You should have a 48 Volt system if you need that level of output.
Second, a charge controller does not feed an inverter. Off-grid inverters run from batteries. Charge controllers recharge the batteries. It is important to keep the ideas separate.
Third, an MC4 connector is designed to go between another MC4 connector and a piece of wire. There is no way the wire end will attach directly to a circuit breaker. Or perhaps I should say "no safe way" as so many people are intent on doing things wrong. Often because they saw some idiot put up a Youtube video about it.
Fourth, 800 Watts of PV as four 100 Watt panels on an MPPT controller: unless you already have the panels there are cheaper options to get that much power from an array with fewer panels. As it is you could put the panels in strings of two each and have four strings. Most sensible way to combine the four strings is wit a MidNite combiner box. It may not cost less than your DIY box, but it's guaranteed to be built right. At least take a look at their design; the MC4 connectors are built-in to the box.
Fifth, the panels will have a maximum series fuse rating on them. This is the most current they can handle as a conductor if something goes wrong. It is usually, but not always, 15 Amps. That is the size of individual string breakers you would use.
Finally, remember you will also need fuse/breaker on the output of the charge controller to the batteries and another on the wire from the batteries to the inverter.
Thanks everyone so far for your invaluable input
And in reply to Mr. Cariboocoot's input, instead of using a single 6kW inverter, I was thinking of connecting 2 3kW inverters using a 48V DC input to the battery bank, i was hoping to assemble a 1500Ah battery bank. Your second and third points have been duly noted. With respect to the panels i was doing my scouting on amazon, didn't know there was a store here as well
any thoughts on using 4 of these, anyone? http://www.solar-electric.com/solar-panels-mounts-kits-accessories/solarpanels/kyocera-solar-panels/kyocera-kd255gx-lfb-255-watt-polycrystalline-solar-panel.html I'm assuming they're 12V panels so i can connect them in series to produce a 48V array, correct? I'm all the way from the Caribbean and relatively new to in depth system solar power system designs, so I'm making sure i have everything understood before I make make the orders, any help and advice would be much, much appreciated -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breakerGreenGen XVIII wrote: »any thoughts on using 4 of these, anyone? http://www.solar-electric.com/solar-panels-mounts-kits-accessories/solarpanels/kyocera-solar-panels/kyocera-kd255gx-lfb-255-watt-polycrystalline-solar-panel.html I'm assuming they're 12V panels so i can connect them in series to produce a 48V array, correct? I'm all the way from the Caribbean and relatively new to in depth system solar power system designs, so I'm making sure i have everything understood before I make make the orders, any help and advice would be much, much appreciated
The are not "12 volt" Panels (Vmp in the range of 17.5 to 19 volts or so):- Number of Cells: 60
- Tolerance: +5%/-0%
- Vmp: 30.4 volts
- Imp: 8.39 amps
- Voc: 37.6 volts
- Isc: 9.09 amps
- 65.43" x 38.98" x 1.8"
- 44.1 lbs.
- MC4 locking connectors
Vmp~30 volts is a very standard panel voltage for Grid Tied and MPPT based charge controller systems. They will not work for a PWM (less expensive) type solar charge controller. And Kyocera panels are very good too.
30 volts is too low of voltage to charge a 24 volt battery bank (need Vmp-array minimum of ~35 volts). As the panels get hot, the Vmp-panel will fall down towards ~24 volts. You need ~28-30+ volts to charge a 24 volt flooded cell battery bank. Two panels in series (Vmp-array~60 volts) will cost you about 40% (60% panel efficiency) of your array's output wattage into a 24 volt battery bank.
-BillNear San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breakerThe are not "12 volt" Panels (Vmp in the range of 17.5 to 19 volts or so):
30 volts is too low of voltage to charge a 24 volt battery bank (need Vmp-array minimum of ~35 volts). As the panels get hot, the Vmp-panel will fall down towards ~24 volts. You need ~28-30+ volts to charge a 24 volt flooded cell battery bank. Two panels in series (Vmp-array~60 volts) will cost you about 40% (60% panel efficiency) of your array's output wattage into a 24 volt battery bank.
-Bill
Thank you very much BB. I am indeed planning to install an MPPT based charge controller, currently scouting some Midnite Classics. You said "30 volts is too low of voltage to charge a 24 volt battery bank (need Vmp-array minimum of ~35 volts)" Is there a formula/theory behind it? And if 2 panels in series would cost me about 40% of my array's output wattage into a 24V bank (i assume this loss would increase for a 48V bank), how can i reduce these losses? -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
When you use an MPPT charge controller you do not 'lose' any power, the mppt CC does some conversion so that 100 Watts in,( less some power to run the MPPT and line loss etc still) equals 100W out. Not so with PWM , if that is what you use you will lose everything above the nominal battery voltage (roughly)
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
thank you westbranch, by the way, can you connect 2 or more inverters to the same battery bank? If so, how can that be done and what are the possible consequences -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
short answer, yes, but what are you attempting to achieve? there are issues to be taken care of if you want 2 inverters. Are you after 240V..?
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
My main aim is to power as much of my household as possible and by chances what are the issues needed to be taken care of? Im struggling to find sizeable inverters (3kW and up) running on 24V DC input, so i was wondering if i can hook up 2, maybe 3, inverters to the battery bank to achieve the desired power -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
Are you wanting 240V?
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
Sure, that would be welcome -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
here are some choices
you would need 2 of these at 24V:
http://www.solar-electric.com/inverters-controllers-accessories/inverters/ouin/oupooffgrand/outback-power-pure-sinewave-inverter-vfx3524.htmll 120V but stackable You can also use an Xformer for 240V
http://www.solar-electric.com/psx-240.html
or one of these at 48V:
http://www.solar-electric.com/inverters-controllers-accessories/inverters/ouin/rasein/outback-power-radian-series-inverter-gs8048.html 120/240
Just examples
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breakerGreenGen XVIII wrote: »My main aim is to power as much of my household as possible and by chances what are the issues needed to be taken care of? Im struggling to find sizeable inverters (3kW and up) running on 24V DC input, so i was wondering if i can hook up 2, maybe 3, inverters to the battery bank to achieve the desired power
You can, for about 2 minutes Then the batteries go flat. If you are wanting 3Kw of power, you need to look to a 48V system, same watt hours, but less loss in system resistances and Peukert losses.
Outback & Schneider/Xantrex make stackable or native 240V capable inverters. I have XW-6048 and it barely grunts when huge loads (3hp floor sander) are thrown at it.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 , -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
Greengen,
OF course I know very little about what you are trying to accomplish, but it seems like you will need a much bigger array. Hearing 6KW inverters and 800 watts of PV in the same sentence is sort of like hearing "fuel efficient" and "1996 F350 with dump body and 460 gas engine" in the same sentence (I have one its a atrocious!). Also You generally want to connect as many modules in series as you can - check out Midnite's string size calculator. You probably wont need series fuses if you have 2 strings. If you have a MPPT CC there is no reason to worry about what the module voltage is.
Best -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breakerEthan Brush wrote: »Greengen,
OF course I know very little about what you are trying to accomplish, but it seems like you will need a much bigger array.
I've done some more extensive research and i've opted to use Kyocera KD325GX-LFB 325 Watt Multicrystalline Solar Modules, so far i've earmarked 3 to import, i use to measure my household's energy consumption, but for the while i plan on sticking with the 6kW inverter, any suggestions on the amount of panels i should include in my PV array? -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
Lets backup a moment here.... Your loads drive the battery bank. And the battery bank+loads drives the solar array. Lastly, the peak loads drive the size of the battery bank and the AC inverter.
To be really helpful, we need to know how much power you plan on using per day. Here is an example of sizing loads for an off grid system. All the below assume that you are conservation minded. Even an efficient set of appliances and loads can be much heavier with teenagers who don't turn things off... Off grid solar system can generate a lot more power during sunny/summer weather--Much less during winter/poor weather. You either have to adjust your power usage, or use a backup genset/over size the system (both are expensive options).- 1 kWH per day (1,000 WH per day)--Smallish system. lights, radio, laptop computer, small water pump
- 3.3 kWH per day--Add a full size refrigertor, well pump, clothes washing machine--About the practical limit for most off grid homes
- 10 kWH per day--Add electric cooking, fans, irrigation, some small amount of A/C--Lots of money for such a system
- 33 kWH per day--full A/C in hot climates, electric hot water, electric cooking--Suit cases full of money to build and maintain such a system
- 3.3 kWH / 5 hours = 0.825 kWH = 825 Watt average load per evening (not even close to a 6 kWatt AC inverter needed--perhaps 1.5-2 kWatt inverter max)
- 3,300 WH * 1/0.85 inverter eff * 1/24 volt battery bank * 2 days storage * 1/0.50 max discharge = 647 AH @ 24 volt battery bank
Based on rate of charge:- 647 AH * 29 volts charging * 1/0.77 panel+controller derating * 0.05 rate of charge = 1,218 Watt array minimum
- 647 AH * 29 volts charging * 1/0.77 panel+controller derating * 0.10 rate of charge = 2,437 Watt array nominal
- 647 AH * 29 volts charging * 1/0.77 panel+controller derating * 0.13 rate of charge = 3,168 Watt array "cost effective" maximum
Princes Town
Average Solar Insolation figures
Measured in kWh/m2/day onto a solar panel set at a 80° angle from vertical:
(For best year-round performance)
Jan
Feb
Mar
Apr
May
Jun
6.29
6.37
6.27
5.88
5.89
5.52
Jul
Aug
Sep
Oct
Nov
Dec
5.74
5.73
5.68
5.72
5.49
5.89
Near equator, June sun minimum average:- 3,300 WH per day * 1/0.52 system efficiency * 1/5.52 hours of sun in June = 1,452 Watt array minimum (based on hours of sun/loads)
For a 12 volt battery bank--You should not plan on pulling more than ~1.5 to 2 kWatts maximum. For a 24 volt battery bank, around 3 to 4 kWatt maximum. If you try to pull more current through the DC wiring--The size/cost of the copper cables makes it difficult to wire and expensive for the copper.
Nothing written in stone--Just some basic guesswork.
Your thoughts?
-BillNear San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
Bill, wow, absolutely wow, I'd love to acquire such knowledge in solar power, I'm a fan of renewable energy based power generation and it'll be an honour to gain such knowledge.
I plan on obtaining a Kill-a-watt soon to measure the energy consumption of various articles in my home. But a couple of 0.75kW pumps, a laptop that's on 24/7, a fan, a small speaker system, a wireless modem and a couple of smartphones <- that's what I'm aiming to power for the while. I'm planning to have 3 325W solar panels in parallel and a 24V battery bank.
I redid your calculations and found i need a 1300W array minimum. I'm currently drawing up a "schematic" for my solar power system. I'd like to upload it and have your criticique on it. -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
GG, you are very welcome.
Going back to loads... Pumps, refrigerators, and even fans can all take a relatively large amount of power. Working to minimize those power needs is usually the first step to solar power.
For water pumps, there are systems that you can allow you to directly connect a smallish solar array directly to your pump/pump electronics. If you need to irrigate and/or pump larger amounts of water to a cistern/holding pond, these type of systems can be very nice.
And, there are folks that have done several kWatt size three phase pumping systems this way with solar--Very cool (but also pretty cutting edge--local companies may not have much experience):Some discussions about VFD (Variable Frequency Drives)... Basically a variable frequency inverter with (typically) three phase output. Used to soft start motors (handy for 3 phase well pumps, or pumps with well head starting capacitor) and can also turn an AC motor into a variable speed motor (very handy for pumping applications).
WELL PUMP and Inverter QUESTION
Wind/solar for large scale pumping etc (out of my depth!)
could use knowledge - using Gould jet pump - transfering from 230vAC to ? DC (new link/thread 10/27/2012)
Help required to design off grid system (information on possibilities to connect "standard VFDs direct to solar panels) (new link 1/13/2013)
For fans--Looking for the most efficient can help too. A standard AC fan may take several hundred watts. A DC fan may take a 1/4 of that (although, generally with a bit less air flow too).
Anyway... That is how I would start.
-BillNear San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
So how would one minimise those power needs? reduced usage? -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
It turns out that older electrical devices usually were not designed to be energy efficient--But just cheap to build.
For example, many well pumps in the US are 1-2 HP range, when a 1/2 HP would work just about as well. And there is the whole idea of "slow pumping"---Basically let the sun pump for 6 hours per day at relatively low rates and fill a cistern/large pressure tank for momentary home needs (or use a second small ~100 Watt pump to pressurize for kitchen sink/shower/etc.).
Pretty difficult to make general suggestions (very broad subject--energy conservation). Instead, look at your loads and decide which one (or several) to attack first.
If you already have a laptop that uses 0.3 kWH per day and a 5 watt cell phone charger--And a pair of 3/4 HP pumps--Look at the pumps first.
Also peak current and total WH (or kWH per day) are sort of two different problems.
For example, a microwave uses 1,500 Watts peak, but only 20 minutes per day:
1,500 Watts * 1/3rd hour per day = 500 WH per day
30 watt laptop * 8 hours per day = 240 WH per day
5 watt USB Charger * 4 hours = 20 WH per day
22 watts of LED lighting * 4 hours = 88 WH per day
750 Watt pump * 6 hours per day = 4,500 WH per day
750 Watt pump may take 2-3 kWatts starting surge...
So--Figure out your present power needs--Cost of larger Off Grid power system vs cost of "new energy conservation appliances/pumps" and see what works out for you. In general, the costs of reduce power needs can be much less than the costs to increase the size/long term maintenance of your off grid power system.
There are many people here that can help you with conservation... I suggest picking a piece at time. Trying to discuss 5 different "things" gets a bit confusing/frustrating to follow.
And if you are already running an off grid power system--Telling us a bit about it and how well it works for you (and roughly where it is located) can be helpful too. Adding a signature to your profile (and going to Advanced editing on your post to turn on signatures) will help keep us from asking the same questions of you.
-BillNear San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
We do have an older model refrigerator (10 years old) and I'm yet to install an off grid power system, I'm fine tuning my designs then I'll starting importing the components. I have attached some images of my desired system and its battery bank. Any critique, corrections and/or advice would be most welcome. Correction: i've opted to replace the 4000W inverter in the diagram with a 3000W continuous 6000W peak pure sine wave inverter manufactured by Nimble
Attachment not found.Attachment not found.Attachment not found. -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
those Nimble models are not made for being hardwired into house wiring , they have extension cord plugins...
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
I personally do not like large numbers of paralleled battery strings. In my humble opinion, 1 string is ideal, many folks like 2 strings (if one string fails, the second can run as as backup until the first is repaired), and 3 parallel strings is about the maximum I would suggest--Unless you have no other choices.
Before you start drawing everything out--Tells us what you are trying to do. AH/Voltage rating of battery bank, how many Watts of solar panel, and you are looking 3 kWatt of 24 volt AC inverter (?).
I am a big believer in "balanced" system design. And to do this, you really need to look at the whole system in total. Once you have done the paper parts list (battery bank size, etc.) and are happy with the theoretical results, you can start researching hardware choices that will support your needs.
There will be lots of trade offs to be made here. If you live somewhere that does not have a wide selection of batteries (voltage, AH, etc.)--You are sort of hosed and force to alter your deign to use what is local (buying batteries from elsewhere can be a pain).
So:
1) know your loads
2) conservation choices (new hardware, reduction of expectations, etc.)
3) repeat #2
4) do the 50,000 foot design (just numbers for battery bank, array, etc.)
4.5) What if/backup design--genset+AC charger specs, spares, etc.
5) start to "push down" to each sub-section (batteries design first--I would suggest)
6) order electronics, wiring, racking, etc.
7) order batteries last (flooded cell batteries will start to "die" if left uncharged for ~1 month or more without charging)
Do not make any orders until you have a plan that works. Buying pieces without a plan will generally not give you good results.
-BillNear San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
Based on semi extensive reading on this forum, I'm leaning towards a 24V battery bank, with an AH rating of 700Ah, I'd like to use solar power to power just my bedroom and the two pumps for now, and a desired wattage of panels to sufficiently and safely charge/power desired battery bank and either a 3 or 4kW pure sine wave inverter
And the theoretical results, where can i find a resource to educate me on the different solar power calculations like the formulas you demonstrated earlier, and also, what do you mean by the 50,000 foot design? -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
50,000 foot view is from a jet airliner (you see the roads, housing patterns, whole city at the same time--Slang). Don't get "tunnel vision" when looking at wiring up a battery bank just yet.
Just ask about the equations--Where we get the derating factors, why we choose 2 days and 50% battery sizing vs something else etc.
Many are just rules of thumbs that work well for us (experience). Basically, very quick to get a basic/functional/reliable design in a few minutes.
And the rules of thumbs are just starting points. If you have "unusual" needs--Then things can be changed/adjusted to better support your needs.
This thread has lots of links to books and other websites if you wish to read more.
http://forum.solar-electric.com/showthread.php?5556-Working-Thread-for-Solar-Beginner-Post-FAQ
-BillNear San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
Thank you so much Bill, your input has been invaluable, i'll start reviewing the material n posts, and should design a more practical system within a week. Can i email you my revised plans for a critique? -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker.
Pretty difficult to make general suggestions (very broad subject--energy conservation). Instead, look at your loads and decide which one (or several) to attack first.
If you already have a laptop that uses 0.3 kWH per day and a 5 watt cell phone charger--And a pair of 3/4 HP pumps--Look at the pumps first.
Also peak current and total WH (or kWH per day) are sort of two different problems.
For example, a microwave uses 1,500 Watts peak, but only 20 minutes per day:
1,500 Watts * 1/3rd hour per day = 500 WH per day
30 watt laptop * 8 hours per day = 240 WH per day
5 watt USB Charger * 4 hours = 20 WH per day
22 watts of LED lighting * 4 hours = 88 WH per day
750 Watt pump * 6 hours per day = 4,500 WH per day
750 Watt pump may take 2-3 kWatts starting surge...
So--Figure out your present power needs--Cost of larger Off Grid power system vs cost of "new energy conservation appliances/pumps" and see what works out for you. In general, the costs of reduce power needs can be much less than the costs to increase the size/long term maintenance of your off grid power system.
-Bill
Hi GreenGen ... The council of trying to determine just what your system will need to do has been given several times in this Thread.
If you are able to slow down a bit, and take some time to consider what your system really needs to do, including measuring loads of those things that you now have that will be used on the new system, you will be much better off.
Trying to choose hardware to provide power, when the amount of power needed, when it will be needed, the peak power, etc are not yet known in real terms can result in having some expensive items that may not really be appropriate for your actual needs
This data need not be perfect, but actual data is the best starting point for any engineering project, IMO.
Have Fun, VicOff 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. -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
GreenGen,
I have sent you a PM with my email address.
As you get better information on your loads--We can help some more here too.
-BillNear San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset -
Re: Advice on this system and can an MC4 connector connect directly to a circuit breaker
green.....
I would say that bill should be your hero due to the amount of time and follow through and work in typing good responces. I do think however, that you miss in two ways if you deal stricly with bill. It seems he doesn't mind as he gave you his email. One of the ways you miss out is when you present what you come up with, there may be someone here that sees what bill might miss (although I don't think he misses much). One of the other ways you lose is by other members not being able to learn with you as you move further. Bill has did most of the work so maby we don't deserve to know everything or maby he is just that much smarter then guys like me.. I do understand that sometimes it may be easier to send things through email then to load them on a forum. I do like seeing how poeple come up with what they need to make stuff work and I also like seeing the answers to guys like us who may not have the knowlage of the experts like bill. I keep watching his responces cause they help me also and someday I may need to help some one else from what I learned here.
These are just my thought for your consideration and also if you both feel more comfortable doing it by email I don't want to be in the way.
Thanks
gww
Categories
- All Categories
- 222 Forum & Website
- 130 Solar Forum News and Announcements
- 1.3K Solar News, Reviews, & Product Announcements
- 192 Solar Information links & sources, event announcements
- 888 Solar Product Reviews & Opinions
- 254 Solar Skeptics, Hype, & Scams Corner
- 22.4K Solar Electric Power, Wind Power & Balance of System
- 3.5K General Solar Power Topics
- 6.7K Solar Beginners Corner
- 1K PV Installers Forum - NEC, Wiring, Installation
- 2K Advanced Solar Electric Technical Forum
- 5.5K Off Grid Solar & Battery Systems
- 425 Caravan, Recreational Vehicle, and Marine Power Systems
- 1.1K Grid Tie and Grid Interactive Systems
- 651 Solar Water Pumping
- 815 Wind Power Generation
- 624 Energy Use & Conservation
- 611 Discussion Forums/Café
- 304 In the Weeds--Member's Choice
- 75 Construction
- 124 New Battery Technologies
- 108 Old Battery Tech Discussions
- 3.8K Solar News - Automatic Feed
- 3.8K Solar Energy News RSS Feed