The BEST way to add batteries to a grid tied solar system. Part 3, FarmCraft101 solar 

Exactly. Very impressive stuff.

+1

Loop moo

Actually this is not an "off grid" system. Not even if you use "quotes". It is a poorly designed manually controlled "AC Coupled Hybrid PV" system. Real AC Coupled Hybrid PV systems are 100% automatic.

Yep they use transfer switch ..

I would disagree on many items in this design. I do think FarmCraft101 has some great diagrams and teaching methods, but it lacks trade smarts and code compliance/safety. There is no reason to re-invent the wheel here. I hope people don't just assume all inverters have this "multi inverter" feature, which is actually for the same models w/ proper distribution panel. As Tofulnc says, the XW6800 hybrid could do it all. Here are my safety/code concerns: 1.)MC cable for HVDC ... not allowed in most states! Use PVC, or EMT. 2.)16.8kW feeding into a 200Amp panel .... almost double the allowed 20% over current by code. 3.)Where is the DC combiner for 3 strings. I believe you said 1 wire for DC run.(actually 3 but need 5) 4.)Why is there a label for AC disconnect on the DC run? 5.)AC couple is not ok for just any brand inverter. Those frequency control funtions are for 2-3 same size and brand inverters with proper distribution box. 6.)Is that a suicide cord being used ... on the gen run .. and manual charge? Way not ok! 7.)Guessing that manual xfer would need a separate lockout box too ... if it was allowable. 8.)I did not see a battery breaker or other DC distribution on low volt side. Bigger bank and cable size could help start large loads using all of the 13kw startup power (maybe 10sec?) from the xw6800. 9.)Proper clearances are not maintained on XW6800 10.)No mention of grounding and reasons for it are a big missing part of safety w/ 380VDC runs in a DIY video. 11.) I have to assume that this addition is without a permit. I feel it is to the advantage for DIY to use inspectors to help make installs a bit more safe, and not void your home owners insurance. 12.)I would never recommend DIY for backup/offrid if the owner did not install the grid tie setup! It is way more complicated and dangerous! Ok ... not to worry. I am not the inspector in your county! But this is a video to help people learn ... right? Why not show a safe more simple approach. Here is are some things missing in your "retrofit strategy". 1.)Cheap solution is rewire array yourself for 10 of 3 panel strings of 100-150VDC. 2.)Put the proper fused DC combiner at the Array. 3.)Pull new wires if needed on DC run. How much can a DIY 300ft ditch and conduit run for a worst case scenario? Not the $1000 to $2000 extra for HV CCs. 2x 80A HVCC would get you to 8.8KW PCT or 10k DC STC if you do not want to oversize array to inverter. 4.)Bigger battery bank, proper batteries, larger inter ties/homeruns, and large xfer switch solves the startup problem. A gen along with gen load balance can also work if that compressor is really needed offgrid! Symmetrical taps would also help! Yes, high current is different than normal wiring. 5.)Realize that you do get 3300W per XWMPPT60 CC, and could go with just 2 for a 9.2karray. Yes ... you can over size an array to inverters or CCs and they just de-rate by firmware for safety when needed! It is completely allowed by the manufacturer and codes. If you want to save on equipment ... this is a place! Panels are cheap! This type of over size of 25% (9.2k x .85 PCT factor = 1.25 x 6.8k) . results in a loss of only about 5-10% depending on climate since peak power only occurs on cold days near noon time. 6.)Realize that a large manual 200A xfer switch could just be a "high power grid tie mode", and then 99% of everything else would just be automatic with the 60A XW automatic xfer. This solves your critical loads problem. Using appropriate size battery bank/ and oversized inter ties will help on motor starts. Does that large compressor really need back up ... instead of a little cheap spare? Running one or two new dedicated circuits for an item is not typically that hard. Making it look good can be hard! 7.) Have to say the already wasted money here is the original system with "optimizers". I would guess the installer got a closeout deal ... after hearing the $1200 price for the 10k inverter .... which was originally more like $2000 plus $2000 more for the optimizers. They are just not needed on a single plane array. Most panels have "bypass diodes" that help minimize losses when a random panel fails or is dirty. Maintenance and monitoring is even a better solution. These, and micro inverters need 4x as many weather tight plugs, which are the most likely part to fail on the array. What a longgggg comment. It helps me stay in design shape when not installing so many systems! Maybe some one reads it ;-)

@@koisolare1266 does electricity. Also PCP.

@@koisolare1266 I read it. I'm impressed. Clearly you know a lot about it. Problem is: It is hard, very difficult to understand without schemes. Do I understand you well? The system of FarmCraft is not safe or not as safe as it should and could be? How much would the system cost if it was setup your way?

@@guzziventure1750 A standard XW6800 system with smaller battery bank is about 10k$ plus another 10k$ for rewire, trench and labor (PV and ground mount additional cost) A general rule for battery backup is 2 to 3x the cost of grid tie. It makes much more since to get a gas/propane backup compressor/gen if you really need that backed up. Battery backup is always questionable if you do not use it more than a week in a year.

The only component I know is the battery 🔋

Thank you!

You are right Some batteries have more stress Because the voltage drops on wires

Terrific but of information. Thank you.

@Paul D - Maybe the Schneider Conext inverter has built in functionality in it's charge controller though which would alleviate or minimize that problem?

Will Prowse recently did a video on that. It’s surprisingly not that simple. I don’t remember why though.

Good point but, I don't think the few millivolts drop in those cables is going to be significant. Imbalance in the capacity of the cells is what causes failure... A chain is as strong as the weakest link... In series cells the one with smallest capacity gets "bullied" by the others. Overcharged at the top end and depleted or even reverse charged at the bottom end.

You do know BYPASS DIODES right.. So a Guy like Wood Seem pretty stupid If he fell for the SERIEL PANEL'S WITH SHADDOWS WIL SHOT THE WHOLE STRING DOWN ... YOU CAN'T SERIUSLY CALL YOU SELF THAT .. AND DONT KNOW. THIS ???? IT Will not shot down the whole string Just bypass the shaddowed panel Same reduktion in watt as paralell But No freaking shut down ... Let's her hos skat you aculey are .. Doe's BYPASS DIODES. Bypass AFFECTED shaded areas on PANELS True Or False !!!!

Hmmm got an email from Kenneth Schultz . but his Channel doesn't have any content. I'll still answer this. but First lets read: Kenneth Schultz to Me... You do know BYPASS DIODES right.. So a Guy like Wood Seem pretty stupid If he fell for the SERIEL PANEL'S WITH SHADDOWS WIL SHOT THE WHOLE STRING DOWN ... YOU CAN'T SERIUSLY CALL YOU SELF THAT .. AND DONT KNOW. THIS ???? Me to Kenneth Schultz... You're Correct on the Bypass Diodes. Monocrystalline panels have those, if part shading will shut off that string. Also if Light is not distributed evenly and overheating. We experimented in a classroom with Simulated Sunlight. That panel didn't want to cooperate, 2 LED lamps were being focused in the middle of the panel and Zip, Nada. Then we added more LED lamps a total of 6 that shed light evenly and Voila' panel worked more efficient. First try the panel did produce voltage but wouldn't turn on the MPPT charger. Second try with 6 lamps it did what we intended to do. (wish I could post pictures here) Third try, we changed panel from Monocrystalline to Polycrystalline and it worked with part shading. They both have Pros and Cons. Yes we had micro inverters then we used optimizers. I'm not offended by your remark, why should I. it also serves as a learning tool for others where everyone benefits. I have installed some panels on RV's but I won't called myself a professional on that field. I've seen some installs that make me want to go deeper into that field. As I stated I admired FarmCraft 101's video.

You're very welcome. I hope you found it helpful!

Please explain how to handle if production is high and load is less battery is full. i have 2kva home UPS sign wave with 2 battery. I would like to add a 3kva solar using micro inverter. Here no grid back feeding mechanism. Presently grid current is passing through my old inverter to entire house. I am not willing to throw out my old inverter for a hybrid and not much space for a big inverter so micro inverter is the only possible way. How can I prevent over production and blowing out my old inverter in low load and high production sunny day?

chuckles

Is there a drain cycle for the batteries in hybrid system?

It gives the amperage readout on the control panel. The amperage does vary some, between 120 and 180 or so, depending on the charge state of the battery bank. It also has a temperature sensor for the batteries that will stop or slow the charging if the batteries get too hot.

This is one main issue I see with the system in the video; AC coupled system with the "Grid-Tie" inverter (GTI) operating/configured as per Grid code can cause: 1. Tripping of the Hybrid Inverter (or both) on low load and high sun conditions (as the GTI try to output a lot more power than required by load conditions - including battery charging), or 2. overcharging of batteries; the Hybrid inverter will not be able to regulate the charging current (from the GTI) as it is not communicating with it - this can shorten battery life, if not damage the batteries - battery dependent) Typically, in AC Coupled systems operating off-grid, where there's no direct communication between the inverters (maybe because of different brands, or simply the option is not available) the GTI inverter should be configured to operate in "Off-Grid" mode, whereby the Hybrid inverter can then "communicate" and control the output power of the GTI by varying the AC frequency (and via Frequency-Shift Power Control (FSPC) for SMA, Active Frequency Shift Power Curtailment (AFSPC) for Schneider or in this case, Power Control Option for SolarEdge); note however that the default "Off-Grid" mode may not comply with Grid code (adjusting frequency range, and adding an additional anti-islanding relay can likely solve this issue, to comply with operation with Grid present). Otherwise, for FarmCraft 01's situation, the SolarEdge StorEdge solution could have proved easier to integrate.

Actually, its is *BEST* for these Lead Acid Batteries to be fully charged at all times. Where did you get you bad information from?

With that being said, a charge controller output would go to the opposite corners of your battery Bank. That makes the input and the output run through the batteries.

Since the 3 banks are wired in parallel why would it pull from the first series string instead of all of them equally?

@16:28 The load side conductors are on the same string. Although their in parallel, it will pull from the closest set first. So, your first string will take most of the load. I would pull from either end for your load and the opposite terminales for you line in. This will act as one big battery this way. the line in has to run all the way to the other end for the load. (not being a smart ass) Think about it. It makes sense. Hope this helps. I'll try to find some links to help out. Your not wrong but I think that it might cause extra strain on that first set.

Agreed, because if the voltage can only come from one, it will, essentially.

Drunkinone can you share a drawing, thanks

We also went through this calculation when considering our setup (and decided against battery backup), you need to add in interest, ie if you invested the money instead of buying the extra equipment there would have been a return, and, over 10 years that may be quite large.

Sorry, I forgot to add... a great video and very informative. Thank you.

Can anyone tell me ,what happens if i connect the 2000 VA generator to wall outlet when the solar grid tie inverter of 1000 VA is working when the grid is not present?

THAT is good information to know!