3 Phase connection

[fresun]

Hello there,

I am designing a commercial PV system of around 12kwp. My design so far has lead me to use a Powerone TL 12.5 inverter 3 phase. The factory has a 3 phase 4 wire (delta ?) supply. The inverter has the following connections
R-S-T-N-PE

Could anyone with 3 phase experience decipher these into cable colours the meter? A schematic of a 3 phase solar connection would be grand.

Thanks in anticipation

 

[snowhead]

Having worked with 3 phase for over 40 years I'll give you a clue.

PE = Earth
N = Neutral

There's only 3 left to sort.

 

[a1colly]

R = l1
s = l2
t = l3

 

[jason121]

I thought it was red yellow blue black is neutral green yellow earth no its
brown black grey blue is neutral oh bugger I will just use black singles and tape them

 

[telectrix]

and i thought R was Rubbish, S whatever new colour that brussels want for yellow, and T was tamper return.

 

[a1colly]

Spot on telectrix

 

[LeeH]

Attention! Put the 3 phase down and please step away from the installation!

 

[telectrix]

R-- read instructions.

S-- study theory

T-- telephone an expert.

 

[Silly Sausage]

I am designing a ...

Try reading the associated literature, you might end up with a better end result!

Or is your company motto, "Designed by internet forum chit chat" ?

 

[Lucien Nunes]

A friend who used to work for Sprecher & Schuh told a story of a panel they built for an Italian factory, which had a bunch of numbered sensor terminals but also some lettered A to Z. After installation they got a call saying it had gone bang and let out the magic smoke as soon as they turned on the power. When he went over to sort it out, he found the guys who wired it had taken the meaning of R, S & T rather literally!

 

[fresun]

Three Phase cable indentification

Inverter terminal= Old Colours= New colours

R= L1 = Red = Brown

S= L2 = Yellow = Black

T= L3 = Blue = Grey

N= Neutral = Black = Blue

PE= Earth = Green/yellow = Green/yellow


I believe this to be accurate?

It's a challenge to get a good understanding of such an in depth and rightly so safety critical trade, the format for studying now I found to be mostly theory which as the old adage goes ' a life time of theory is worth an ounce of practice'

I am finding in order to gain the understanding level that would have been achieved by the original several years as an apprentice on the tools, it is now necessary to pool all of knowledge, Literature, Web, technical support.

Looking for position as apprentice / improver in the South Essex area, to hone my Full scope + Part P and MCS PV Quals.

Thanks for your kind advice and patience
Sorry for poor layout of my table 'auto format wants to justify it'

 

[Lucien Nunes]

Yes, it's correct, but it's also rather fundamental. Your reference to delta in the OP also suggested that you don't yet have the knowledge-base about 3 phase systems that I would anticipate in someone doing design work. I agree that even with the help of the WWW it can still be tricky to get exactly the right piece of info in a busy world where everything keeps changing but you definitely need the basic theory to underpin this.

 

[fresun]

Indeed the quest for knowledge is never more needed now. On the brighter side, i had anticipated a substantial FIT rate cut on 1st January, however the rates are substantially unchanged up to 31st march 2014. More time to get this installation perfect.

www.ofgem.gov.uk/ofgem-publications/84190/fitpaymenttable1january2014tariffs.pdf

 

[Worcester]

@fresun, based on your comments I do hope this is a desk top study / college exercise not a real live project.

In order to obtain the Feed In Tariff, you cannot do a 'diy' install, it has to be installed and commissioned (which means a full audit on the the design process - so you might as well let them do that) by an MCS certified company, that company has to show that it has the skills to do the type of work that it carries out.

- is this areal live project or desktop study?
- are you MCS certified?

 

[Gavin A]

Three Phase cable indentification

Inverter terminal= Old Colours= New colours

R= L1 = Red = Brown

S= L2 = Yellow = Black

T= L3 = Blue = Grey

N= Neutral = Black = Blue

PE= Earth = Green/yellow = Green/yellow


I believe this to be accurate?

It's a challenge to get a good understanding of such an in depth and rightly so safety critical trade, the format for studying now I found to be mostly theory which as the old adage goes ' a life time of theory is worth an ounce of practice'

I am finding in order to gain the understanding level that would have been achieved by the original several years as an apprentice on the tools, it is now necessary to pool all of knowledge, Literature, Web, technical support.

Looking for position as apprentice / improver in the South Essex area, to hone my Full scope + Part P and MCS PV Quals.

Thanks for your kind advice and patience
Sorry for poor layout of my table 'auto format wants to justify it'

top tip - if you don't know what you're doing with 3 phase, but want to install 3 phase jobs, then simply hire an experienced commercial / industrial electrician to work with you on the installation, and focus on the panel installation side yourself.

By work with you, I'd mean paying him to spend at least half a day checking your design specs / determining the design specs in advance, not just turn up to the job, as you need to make sure you actually have the right kit bought when you get to site or you could have a wasted day / serious problem to rectify afterwards.

Also, double check in advance that the electrician is aware that the volt drop limit for solar PV cables should be 1% at full generation.

Or ask another company that is experienced in solar commercial installs to partner with you on the project so you can learn from them etc.

Please don't try to wing it.

 

[Worcester]

@GavinA, it was this post by fresun that has me worried for his and his clients safety:

"It's a challenge to get a good understanding of such an in depth and rightly so safety critical trade, the format for studying now I found to be mostly theory which as the old adage goes ' a life time of theory is worth an ounce of practice'

I am finding in order to gain the understanding level that would have been achieved by the original several years as an apprentice on the tools, it is now necessary to pool all of knowledge, Literature, Web, technical support.

Looking for position as apprentice / improver in the South Essex area, to hone my Full scope + Part P and MCS PV Quals."

 

[Gavin A]

@GavinA, it was this post by fresun that has me worried for his and his clients safety:

I was assuming 'MCS solar pv quals' meant fresun was MCS certified, and in a bit of a similar position to me when I first started, and rapidly realised the Part P short courses didn't actually equip you for anything like all the situations you find yourself in when wiring in customers houses, despite having a decent working knowledge of renewables and electrics in a non domestic setting.

Simple answer for me was hire a time served spark initially self employed on a job by job basis til we took them on full time, and work alongside them, building up my knowledge, skills and experience in the process, then work our way up through the domestic, onto a few 10kWp, then bigger systems.

I was incredibly glad I'd done that when on pretty much our next job it turned out on testing that the house was supposed to be TN-CS, but the suppliers earth had actually come disconnected up the street. The spark was straight on the phone to the DNO, then a couple of hours later they rocked up, checked their earth connections and came back to inform us they'd sorted it. I really doubt I'd have trusted my test results enough at that point to be confident in telling the DNO their earth supply wasn't present.

So yes, I'd be worried if they were going to do it by themselves, less so if they bring the necessary experience on board for the job, and take their advice, and learn from them.