Does Your System Qualify as a "Separately Derived Source"?

[fafrd]

Again off topic.

It’s your thread and I did not mean to hijack it, so I’ll take my questions elsewhere.

 

[Ozark Tinkering]

This is the problem. It could be but if is not separately derive you need an inter connect agreement with the utility. A generator can be separately derived or not. Tie your output, neutral to their current carrying conductor or share the same ground, you need a utility agreement. If you can keep them separate while you generate, it is an sds.

My Enphase grid connected system doesn't have its own neutral. Straight 240.

 

[Tecnodave]

My Enphase grid connected system doesn't have its own neutral. Straight 240.

OK so my Magnasine MS4024 main transformer does have a center tapped main winding so when it is in battery charge mode this transformer is in parallel with the utility transformer on the utility side, Is it also helping balance the non balanced load in the rest of the installation? Is this not code? In pass through mode it can and does couple both halves of the transformer and will output 120/240 even when on a 120 volt only service. There are several models made by Schneider Electric as well that do have this capability!

 

[Ozark Tinkering]

OK so my Magnasine MS4024 main transformer does have a center tapped main winding so when it is in battery charge mode this transformer is in parallel with the utility transformer on the utility side, Is it also helping balance the non balanced load in the rest of the installation? Is this not code? In pass through mode it can and does couple both halves of the transformer and will output 120/240 even when on a 120 volt only service. There are several models made by Schneider Electric as well that do have this capability!

Do you have a diagram?

 

[Ozark Tinkering]

OK so my Magnasine MS4024 main transformer does have a center tapped main winding so when it is in battery charge mode this transformer is in parallel with the utility transformer on the utility side, Is it also helping balance the non balanced load in the rest of the installation? Is this not code? In pass through mode it can and does couple both halves of the transformer and will output 120/240 even when on a 120 volt only service. There are several models made by Schneider Electric as well that do have this capability!

That's an SDS correct?

 

[Tecnodave]

That's an SDS correct?

I do not understand SDS.

My Magnasine is model MS4024AE, it is the forerunner of the MS4024PAE, It is 120/240 volts They are essentially the same but the PAE’s can do load sharing where the AE models are inverter or charger, no load sharing and not parallable as the PAE models are.

 

[Tecnodave]

Magnasine partial schematic....

 

[Tecnodave]

It does qualify L1 first, then L2 , and does qualify L1 and L2 are 180 degrees out of phase, therefore no two generators and no 2 legs of three phase (WYE)

 

[Tecnodave]

That's an SDS correct?

Its been a long day.....It is an SDS....

 

[Ozark Tinkering]

Let's go back and decide if this is really a Separately Derived System or a Grid-Tied System.

Near the front of the NEC is Art. 100 and NEC Art. 100 defines a Separately Derived System as “An electrical source, other than a service, having no direct connection(s) to circuit conductors of any other electrical source other than those established by grounding and bonding connections.”
That describes most of us.

But does it? your wires from the inverter to the grid connect directly to the service, not through a transfer switch, which isolates 2 different power supplies and can include the neutral. Today's inverters are "transformer less"

Grid connected solar systems using an inverter are NOT separately derived systems.

An SDS requires a 3-pole transfer switch for a single phase

Separately derived systems are power sources with no direct electrical connection between any of the circuit conductors and supply conductors. For example, no direct connection exists between the primary and secondary winding of a delta-wye transformer. Generators, converter windings, UPS systems, and solar photovoltaic systems are separately derived systems only when all circuit conductors — including the grounded (neutral) conductor — are independent of the supply conductors. If you wish to use a separately derived system, you must use a 3-pole transfer switch for a single-phase, 3-wire system, or a 4-pole transfer switch for a 3-phase, 4-wire system [Art. 100 definition and Sec. 250-20(d) FPN No.1].

A grid tied system has to comply with Art.690.12(1) through (5)

Rapid Shut Down​

In 2014, the National Electrical Code included a new requirement. 690.12(1) through (5) A short requirement, only six sentences.


PV system circuits installed on or in buildings shall include a rapid shutdown function that controls specific conductors in accordance with 690.12(1) through (5) as follows.

1. More than 5’ inside a building, or more than 10’ from a PV array
2. Controlled conductors shall be limited to not more than 30V and 240 volt-amperes within 10 seconds of rapid shutdown initiation.
3. Voltage and power shall be measured between any two conductors and between any conductor and ground.
4. The rapid shutdown initiation methods shall be labeled in accordance with 690.56(B).
5. Equipment that performs the rapid shutdown shall be listed and identified.
   But those six short sentences had a big change on PV system design. Gone were the days of simply wiring the solar panels, or modules, to the grid tied inverter or charge controller through a simple pass-thru or combiner box. Rapid ShutDown (RSD) has a noble cause. It is to protect the firefighters trying to put out a fire in your home or business. Even when they turned off the grid power to your house, and the inverter automatically shut itself off (in accordance with UL1741), the wires from the solar array all the way down into the inverter or controller were still live. In grid tied systems, they could have as much as 600VDC. Combine that voltage with a firefighter’s ax to vent the roof, and you have a disaster on your hands.

 

[Tecnodave]

The magnasine does not depend on the grid to be up, It operates standalone when in invert mode, the internal AC power relay does disconnect with the grid when in invert mode, it does not “see” the grid. It does not synchronize with the grid

A grid tie system does a shutdown when the grid is down, This system disconnects from the grid when the grid is not present through it’s power transfer relay. It is two pole, not 3 pole, neutral stays connected

It is not mounted on a building.....therefore I do not require a “rapid shutdown system”

Lets be clear about my utility, I dont live “down town” Im quite remote, My POCO service to my house is 30 amps 120 volts. The distribution transformer is approx 125 feet from the house. It is single phase 120 volts originally installed long ago, date not recorded, utility badge on pole is 1933, The transformer has been replaced with the “standard“ 8kv to 120/240 split phase but the house panel is 120 volt 30 amps, mind you this is a very old house, It has never “officially” been upgraded to modern standards. This county did not have a building department until 1956. Im “grandfathered” , the building department has never “officially seen” the house. There is no building permit, that is not required as it is a “grandfather”

I have a rather large old “class A” motorhome that is still registered with the State as a vehicle, Therefore it is a “motor vehicle” . In California for a vehicle to be a “motorhome” it must have 3 of the following 4 items....sink, stove, refrigerator, bed. two of these items have been removed therefore it is “not a motorhome” and not under the authority of the “State housing authority” , which in California regulates the “housing accomodations” of the motorhome....”sets the standards”...for the “living accommodations” but it is still a vehicle regulated by the STATE which in California trumps the county, If the state regulates it the county cant touch it. I also have a “trailer” with a “permanent registration” . It is 53 feet long, an ex 18 wheeler trailer, again registered by the State, not required to have yearly registration , which again trumps the county, no permit required. The “ex-motorhome” houses the solar system , power room, and battery banks and two arrays. The trailer is completely covered by more array‘s but houses no other parts of the solar system, Its a workshop/ storage space, The arrays completely overhangs the trailer and the motorhome.

Yes, very deliberately loopholing the county.....and the building department....they are god awful here.

The house is connected to the power house by several “CS” cord 4 wire construction standard cord.
50 amps, 240volts..it plugs in...“beyond the outlet”

I can charge from the POCO in an emergency but I do not need to do that. So am I a “grid tie”, dont think so, This is a “separately derived system”, both can be powered at the same time with common grounding. but there is no power transfer back to the utility.

Here in California we have what is called PSPS...Public Safety System Shutdown where the state PUC mandates public power system shutdown to protect the public from our lame POCO...PG&E , Pacific Gas & Electric really ....Pigs, Goats, and Elephants (the workers named themselves that) which would rather give bonuses to executives than maintain the grid infrastructure but Im stuck in a loophole, To have a occupancy permit I must have a utility power connection and use it, I use the minimum required $5.00/month to not rock the boat...again loopholing the powers that bee....

BUT......My work as an electrician totally toes the code in every aspect, I do not fudge the code or OSHA or any safety standards, period, not if, and or but. I absolutely will not violate the code in my work, way too much liability. I have never had a burn down, never will. I will not touch a home or building system that is not U.L. . I do not do solar specifically but do get involved in home remodeling where there is an existing solar system, almost exclusively for remodels for sale. If it is non-U.L. it is removed or I will not get involved. Again Liability. The bulk of my commercial work is the the farmers here, California is an ”Agricultural” state, Santa Cruz County ....Pajaro Valley is the “Strawberry capitol of the world” We generate far more dollars per acre than any other agricultural area in the country....A Strawberry farmer that loses his water may well lose a million dollars in days....I am on call 24/7/365 for a fee....96 family farms in my book, I have no need to mess with houses. I can replace a 100 h.p. 480 volt pump panel on a 4 day holiday weekend...with no electrical houses open...might not be brand new stuff but I will have water pumping, If the pump itself is broke, that is the pump guy, Its down there 400 feet or so. I can get a “loaner” 100 h.p. turbine pump motor within a few hours with the rebuild order, day or night, how bad do you need it ? My experience comes from Industrial electrical, retired from a major corporation many years ago. I do small scale off grid systems for serious off gridders here locally but if you do have grid power here you cannot install a off grid system here, you must use the grid.

 

[MrM1]

There are several models made by Schneider Electric as well that do have this capability!

Magnasine partial schematic....

@Tecnodave would you say this diagram also applies or is similar to the Schneider Conext SW series? If so that is a great explaination of it's wiring. Watching this thread.

 

[Tecnodave]

@Tecnodave would you say this diagram also applies or is similar to the Schneider Conext SW series? If so that is a great explaination of it's wiring. Watching this thread.

Yes The Schneider is wired the same way

 

[Tecnodave]

The XW is entirely a different beast, I have never been into one of those , but I have been into the Conext SW as well as the Trace SW4024

 

[MrM1]

Yes The Schneider is wired the same way

Thanks, so I am now watching this thread with interest. Interesting to see that the Neutral from the Grid input is not part of the transfer relay for L1 and L2 input. My assumption is that the N/G bond for the Neutral and Ground are back at the main panel. And that is NO OTHER bond for N/G after the inverter regardless if you are on grid pass thru or off grid mode in the inverter?

 

[Tecnodave]

So I did not say quite that, I do beleive there is another relay that optionaly removes/restores the neutral ground bond if connected thay way, for use when the Magnasine is used in an RV, removes the bond when pluged into shore power and restores the bond when disconnect from external power, this is a user option.

 

[Ozark Tinkering]

The magnasine does not depend on the grid to be up, It operates standalone when in invert mode, the internal AC power relay does disconnect with the grid when in invert mode, it does not “see” the grid. It does not synchronize with the grid

A grid tie system does a shutdown when the grid is down, This system disconnects from the grid when the grid is not present through it’s power transfer relay. It is two pole, not 3 pole, neutral stays connected

It is not mounted on a building.....therefore I do not require a “rapid shutdown system”

Lets be clear about my utility, I dont live “down town” Im quite remote, My POCO service to my house is 30 amps 120 volts. The distribution transformer is approx 125 feet from the house. It is single phase 120 volts originally installed long ago, date not recorded, utility badge on pole is 1933, The transformer has been replaced with the “standard“ 8kv to 120/240 split phase but the house panel is 120 volt 30 amps, mind you this is a very old house, It has never “officially” been upgraded to modern standards. This county did not have a building department until 1956. Im “grandfathered” , the building department has never “officially seen” the house. There is no building permit, that is not required as it is a “grandfather”

I have a rather large old “class A” motorhome that is still registered with the State as a vehicle, Therefore it is a “motor vehicle” . In California for a vehicle to be a “motorhome” it must have 3 of the following 4 items....sink, stove, refrigerator, bed. two of these items have been removed therefore it is “not a motorhome” and not under the authority of the “State housing authority” , which in California regulates the “housing accomodations” of the motorhome....”sets the standards”...for the “living accommodations” but it is still a vehicle regulated by the STATE which in California trumps the county, If the state regulates it the county cant touch it. I also have a “trailer” with a “permanent registration” . It is 53 feet long, an ex 18 wheeler trailer, again registered by the State, not required to have yearly registration , which again trumps the county, no permit required. The “ex-motorhome” houses the solar system , power room, and battery banks and two arrays. The trailer is completely covered by more array‘s but houses no other parts of the solar system, Its a workshop/ storage space, The arrays completely overhangs the trailer and the motorhome.

Yes, very deliberately loopholing the county.....and the building department....they are god awful here.

The house is connected to the power house by several “CS” cord 4 wire construction standard cord.
50 amps, 240volts..it plugs in...“beyond the outlet”

I can charge from the POCO in an emergency but I do not need to do that. So am I a “grid tie”, dont think so, This is a “separately derived system”, both can be powered at the same time with common grounding. but there is no power transfer back to the utility.

Here in California we have what is called PSPS...Public Safety System Shutdown where the state PUC mandates public power system shutdown to protect the public from our lame POCO...PG&E , Pacific Gas & Electric really ....Pigs, Goats, and Elephants (the workers named themselves that) which would rather give bonuses to executives than maintain the grid infrastructure but Im stuck in a loophole, To have a occupancy permit I must have a utility power connection and use it, I use the minimum required $5.00/month to not rock the boat...again loopholing the powers that bee....

BUT......My work as an electrician totally toes the code in every aspect, I do not fudge the code or OSHA or any safety standards, period, not if, and or but. I absolutely will not violate the code in my work, way too much liability. I have never had a burn down, never will. I will not touch a home or building system that is not U.L. . I do not do solar specifically but do get involved in home remodeling where there is an existing solar system, almost exclusively for remodels for sale. If it is non-U.L. it is removed or I will not get involved. Again Liability. The bulk of my commercial work is the the farmers here, California is an ”Agricultural” state, Santa Cruz County ....Pajaro Valley is the “Strawberry capitol of the world” We generate far more dollars per acre than any other agricultural area in the country....A Strawberry farmer that loses his water may well lose a million dollars in days....I am on call 24/7/365 for a fee....96 family farms in my book, I have no need to mess with houses. I can replace a 100 h.p. 480 volt pump panel on a 4 day holiday weekend...with no electrical houses open...might not be brand new stuff but I will have water pumping, If the pump itself is broke, that is the pump guy, Its down there 400 feet or so. I can get a “loaner” 100 h.p. turbine pump motor within a few hours with the rebuild order, day or night, how bad do you need it ? My experience comes from Industrial electrical, retired from a major corporation many years ago. I do small scale off grid systems for serious off gridders here locally but if you do have grid power here you cannot install a off grid system here, you must use the grid.

Yeah so I have a little experience in my home state of California albeit a few years back. I sat for the California Journeyman exam in 2004 a year after sitting for my Arkansas master exam, a full 2 years before the state began enforcement...scored a 97. I've been inspected by San Diego city inspectors on Class1 Div.1 installations and passed first time around. Interesting thing about the 2 states is Arkansas actually accepts the new code every 3 years before California does. I think Ca. is still using 2017?
To be clear I'm not telling you what you have set up. I'm simply providing you a code reference so you can better understand what an inspector will require. The code isn't a "how to" book it just stipulates the different requirements. I do all my off-grid stuff on the down and dirty too, that's why we need to understand where our line is.

 

[Tecnodave]

It totally amazes me as to the requirments from one locality to another. Santa Cruz is one of the smaller counties but we have the second largest building department in the state. Santa Clara county is next door and has 5 times the population but our building department is far larger , regulated to death.....LOL I have a property in Alaska, we dont have a building department. You build it, you have to live with it. There is no-one to certify your work in most boroughs.
I bought a tear down Butler Steel building here in California and shipped it up and reassembled it there, no permit, no one to ask, just do it. They have never taxed me on it.

Our local school system had no computers, I rounded up many throw outs from here and rented them to the schools for $5.00 / year for 40 to start, many more now.......keeps the admin from selling them....taxes paid.

We Sourdoughs have a way about regulators.....treat them like mushrooms....feed them shit and keep them in the dark.

 

[Tecnodave]

Thanks, so I am now watching this thread with interest. Interesting to see that the Neutral from the Grid input is not part of the transfer relay for L1 and L2 input. My assumption is that the N/G bond for the Neutral and Ground are back at the main panel. And that is NO OTHER bond for N/G after the inverter regardless if you are on grid pass thru or off grid mode in the inverter?

Just check my Magnasine manual. The neutral ground bond relay is activated by grounding the green wire in the connection box. Connecting this to ground activates the neutral ground relay and the neutral is bonded when off grid and relay opens the bond when L1 is powered. Cap it and no neutral bond is done in the magnasine. Perfect solution

 

[Ozark Tinkering]

It totally amazes me as to the requirments from one locality to another. Santa Cruz is one of the smaller counties but we have the second largest building department in the state. Santa Clara county is next door and has 5 times the population but our building department is far larger , regulated to death.....LOL I have a property in Alaska, we dont have a building department. You build it, you have to live with it. There is no-one to certify your work in most boroughs.
I bought a tear down Butler Steel building here in California and shipped it up and reassembled it there, no permit, no one to ask, just do it. They have never taxed me on it.

Our local school system had no computers, I rounded up many throw outs from here and rented them to the schools for $5.00 / year for 40 to start, many more now.......keeps the admin from selling them....taxes paid.

We Sourdoughs have a way about regulators.....treat them like mushrooms....feed them shit and keep them in the dark.

I sold the farm in Ca. back in '92 and bought land in the Ozarks. County ordinance in Ca. required a permit and approved plans for a shed with 100sq.ft. or more of roof space. That's the county, cities are magnitudes worse. I think just the school tax per foot to buy the permit to build my home there was $1.50 sqft? I knew I had arrived in heaven when I saw a temp power pole next to a camper shell with a 200amp service. The outhouse wasn't far away and a 500gal polytank for siphoning from Gray Spring was in the bed of his pickup. They've tightened up a little by now, but out in the county the only permit you need is for septic (if you get it).10 acres or more and they won't be messing with you on that either.