Confusion over PV connection to grid

[Exfarmer]

out of interest if there was a power cut in high summer at noon where would ones solar electricity go

No power is produced as the inverters shut down. The voltage is still there in the DC circuit. Only there is no flow of current.

 

[akaPABLO01]

Inverters have 2 modes. Grid mode & island mode. Grid is obviously connected to the network and unless there is connection it'll hibernate a push the circuit back roof to inverter as Exfarmer explains.

The other mode is Island. This lets the inverter produce electricity with no AC network connection. Now you could have a power cut and switch to island mode and power your farm but, it's illegal. Some poor sod could be working on the line that's shut down and you start sending down power.

So island mode is only used in remote array not connected to the grid.

 

[f0ster]

if you comply with regs it is not possible to power the grid from your inverter in the event of a grid power cut. this facility is built in to all inverters and if you have an inverter that is capable of working without the grid there has to be additional protection, ie a g59 relay. this is capable of disconnecting the grid in micro seconds. I hope people are not paying attention to your miss information. also even tho g59 protection is built in to inverters if you install a large system the dno will require a g59 relay as additional protection anyway.

 

[akaPABLO01]

if you comply with regs it is not possible to power the grid from your inverter in the event of a grid power cut. this facility is built in to all inverters and if you have an inverter that is capable of working without the grid there has to be additional protection, ie a g59 relay. this is capable of disconnecting the grid in micro seconds. I hope people are not paying attention to your miss information. also even tho g59 protection is built in to inverters if you install a large system the dno will require a g59 relay as additional protection anyway.

Lol. I will be compiling my role call later of participating members and their roles in this thread.

Relays prevent power surge. This stops your equipment blowing up and complies with grid parameters.

I am the only one who has actively sought fact and received confirmation of my original statement by 2 seperate DNO as well as 2 inverter manufacturer engineers. Stick that in your pipe.

All your energy enters grid. You do benefit from this but will never use it unless you have battery storage.

@jcb360 lol

 

[f0ster]

it is called a relay but it is actually a micro controller that monitors the grid looking for various parameters to be exceeded and then disconnecting

 

[Chickcatcher]

Inverters have 2 modes. Grid mode & island mode. Grid is obviously connected to the network and unless there is connection it'll hibernate a push the circuit back roof to inverter as Exfarmer explains.

The other mode is Island. This lets the inverter produce electricity with no AC network connection. Now you could have a power cut and switch to island mode and power your farm but, it's illegal. Some poor sod could be working on the line that's shut down and you start sending down power.

So island mode is only used in remote array not connected to the grid.

"aka" I am pleased to have read the above and had Grid/Island explained. Could you now help me with when The Grid is of line and my backup generators are working how do the inverter's know this as in power cut situations they are aware and wont connect. Thanks in anticipation. R

 

[jcb360]

Lol. I will be compiling my role call later of participating members and their roles in this thread.

I am the only one who has actively sought fact and received confirmation of my original statement by 2 seperate DNO as well as 2 inverter manufacturer engineers. Stick that in your pipe.

All your energy enters grid. You do benefit from this but will never use it unless you have battery storage.

@jcb360 lol

We have no proof of the detail those conversations other than your word.

Yet again, you are wrong.

I conclude that you are now blatantly trolling this forum for your amusement.

 

[f0ster]

I don't believe he is enjoying it. He is just putting on a brave face

 

[Exfarmer]

"aka" I am pleased to have read the above and had Grid/Island explained. Could you now help me with when The Grid is of line and my backup generators are working how do the inverter's know this as in power cut situations they are aware and wont connect. Thanks in anticipation. R

Normally speaking your inverters will come back into production with the Generator going depending where the independent isolator switch is.
it is normally reckoned to be a good thing for the generator isolator to be after the Inverter feed to the supply, but this is not always possible.
I would recommend the PV is isolated and turned off when a generator is running, although I have no scientific knowledge in this area

 

[Chickcatcher]

Normally speaking your inverters will come back into production with the Generator going depending where the independent isolator switch is.
it is normally reckoned to be a good thing for the generator isolator to be after the Inverter feed to the supply, but this is not always possible.
I would recommend the PV is isolated and turned off when a generator is running, although I have no scientific knowledge in this area

Hi, Ex. All connections to grid are managed by "auto" switching, power off, mains contactors drop out, activating generator start, energising none mains contactor to engage and liven up the system. Power back on immediately reverses situation.
But while the generator is running the Pv never reactivates they just read "Grid Fault"

 

[Exfarmer]

This may be for a number of reasons
firstly your PV may feed in between the Meter and the automatic switchover. This would mean there is no power at that point.
It may because their is an auto switch disconnecting the solar.
I believe also that the power from a generator is somehow different and the inverter realises this. I am no physicist so may be talking ballcocks on this last point

 

[f0ster]

A genny is not always producing a fixed stable voltage and with the complex electronics in an inverter it is best to isolate the Inverter for the short duration it is not needed.

 

[akaPABLO01]

I'm currently on the road and will answer all when free.

The good news is I've just made contact with metering. More to come

 

[jcb360]

The good news is I've just made contact with metering. More to come

On a Saturday afternoon........how convenient!

 

[Chickcatcher]

A genny is not always producing a fixed stable voltage and with the complex electronics in an inverter it is best to isolate the Inverter for the short duration it is not needed.

We did have a problem with an inverter when the Generator was not kicking out the correct Htz.
@Exfarmer Pv feed is after the auto changeover contactors. There must be something that it is not seeing as a "Grid connection"

 

[f0ster]

if the genny is producing 50hz it should be ok but the hz can fluctuate with engine revs and as soon as the hz drops out of spec the inverter will disconnect.