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newman

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Oh dear its happend again,,please rember everybody including Mr MANATOR this forum is my only soruce of usfull information,I do feel we are getting close to a solution but if the thread keeps getting closed down it limmits the amount of information avable to everybody,

,I DO NOT know who Ivor Dispatch is but if he is the installer it is in his intrests to keep getting the thread closed,so please MR MANTOR be a bit more tolerent

 
Can I make a proposal?

Perhaps off-topic discussion of which cable can or can`t do this or that needs to have a separate thread?

Then maybe Newman can have HIS (he is, after all, the O/P ) questions addressed, without so much sideline referreeing?

If mods agree, perhaps Dave`s post above could be used to start the new thread? May be the best solution possible?

mr kme

mr smith has moved the post you refer to

it is now in the photovoltaic section

titled

cable suitability for dc

mr smith repeats the warning issued on that thread

anyone railroading this thread off topic

will incur infractions

thankyou

mr smith

 
Oh dear its happend again,,please rember everybody including Mr MANATOR this forum is my only soruce of usfull information,I do feel we are getting close to a solution but if the thread keeps getting closed down it limmits the amount of information avable to everybody,,I DO NOT know who Ivor Dispatch is but if he is the installer it is in his intrests to keep getting the thread closed,so please MR MANTOR be a bit more tolerent
Newman, I am not your installer I have only posted as I have had to trouble shoot on similar problem installs, installed by others may I add. All of my remarks about volt drop and dc cables are correct ,, the 1% rule is a guide and swa is listed in the dti guide as suitable for dc if conditions are met. I can not be blamed for your post getting pulled, when some will not read the documents they shout about .

I hope your install works out OK

If you could post the voltage AC at low output levels less than 300w

Thanks

 
Last edited by a moderator:
Newman, I am not your installer I have only posted as I have had to trouble shoot on similar problem installs, installed by others may I add. All of my remarks about volt drop and dc cables are correct ,, the 1% rule is a guide and swa is listed in the dti guide as suitable for dc if conditions are met. I can not be blamed for your post getting pulled, when some will not read the documents they shout about .I hope your install works out OK

If you could post the voltage AC at low output levels less than 300w

Thanks
OK,

Here are some voltage readings

532w 2.1a 243v

276w 1.1a 240v

267w 1.1a 237v

251w 1.0a 240v

187w .7a 238v

169w .6a 240v

161w .6a 241v hope this helps

 
OK gentlemen, this thread will now remain open and be used solely for the discussion presented by Newman.

Any off topic remarks without prior consideration will be deleted, keep all posts factual, and based on sound electrical knowledge.

If you have a query then try to phrase that query properly, I and other moderators can tell when sarcasm is used so be warned.

For the purpose of this debate those posts above are excluded from these rules, but those below will be dealt with accordingly and suitably.

 
OK gentlemen, this thread will now remain open and be used solely for the discussion presented by Newman.Any off topic remarks without prior consideration will be deleted, keep all posts factual, and based on sound electrical knowledge.

If you have a query then try to phrase that query properly, I and other moderators can tell when sarcasm is used so be warned.

For the purpose of this debate those posts above are excluded from these rules, but those below will be dealt with accordingly and suitably.
Thankyou

---------- Post Auto-Merged at 20:12 ---------- Previous post was made at 19:59 ----------

I had the installer round today , I showed him page 3 of the SMAs Grid Connection Technical Information guide

I highlighted the graph which showed .4 grid impeedence at 250v would only allow me to generate less than 2KW

He said the graphs are for G59 cut off values as mine are at G83 the graphs are irrelevant .........does anybody know if he is right

---------- Post Auto-Merged at 20:39 ---------- Previous post was made at 20:12 ----------

Also we discused a new route for the cable,this means digging up my yard ,big job ,but it alows him to shorten the cable to 54 meters

So according to his calculations we can fit 25mm cable and be OK

The cable he wants to fit is a SWA 25mm2 TWIN + Armour XPLE

I hope he's correct

 
1. As previously stated the installer is a MUPPET - This is now a known fact2. After such a load of agro and knowing 1 above do you trust his calculations

3. How on earth would he know if the graphs are for G83 or G59 - I doubt he knows the difference - Going on form this WITHOUT the SMA graphs (which you dont need) its just a question of VOLTAGE

4. Dont fit a 2 core - i did PM you - the cost difference is negligable, yet again the INSTALLER is a MUPPET

Ill leave it to you as I have had enough of this discussion now......

Good Luck

edit: Whilst you may be able to use the SWA armour as the earth (i havent checked GN8) i just dont like it for the reasons of corrosion and long term installation, the solar is meant for a 25 year term, will the SWA be as good in 25 years, who knows.....
Point

1.Yes agreed

2.No I don't

3.He says, Uacmax =253v means the graph is for G59, I have no idea

4. I agree with you

Dont leave me now I need you:worship

 
OK,OK,here are som photos View attachment 3710View attachment 3711View attachment 3712View attachment 3713View attachment 3714

one of the house CU,one of the inverter,one of the roof trusses,one of the barn with the panels on

---------- Post Auto-Merged at 18:04 ---------- Previous post was made at 17:23 ----------

Well he's right in saying that 253 is G59 but he's totally wrong and obviously hasnt read the documentWith regards the SMA chart, As far as i can see SMA being German then the chart is for grid impedance for VDE standards in Germany - VDE 0126-1-1 (not G83 or G59) - Now this leads me on to say has this document any relevance to uk standards ? Not that it matters in reality as it can be done other ways

He has 264Volts at the top end to play with, its almost going to be like saying to him "Do you feel lucky Punk" :slap

Is he paying for this or are you having to pay a thing towards it ?

If it doesnt work will he do it again for free ?

As he seems to have admitted he's wrong and the install was a c*** up then is he going to re-imburse your lost fits ?

You never did answer the question - Did you ask him why it isnt signed off to Part A of the building regs with a structural survey ?

And we never got any photos ?

Seems to be a one way street.....
He's paying'but I will offer a contrabution (we all have to eat)

He has said he will not leave till its right

The solar has been working at full power for about three quarters of the time(no sun) I think its not worth the hassel with the fits

No I havent asked about the structural survey, but a couple of my friends have had bigger PV systems on their barns with structural survey done and they did not need anything doing,so I am not that worried

 
OK,OK,here are som photos View attachment 3710View attachment 3711View attachment 3712View attachment 3713View attachment 3714one of the house CU,one of the inverter,one of the roof trusses,one of the barn with the panels on

---------- Post Auto-Merged at 18:04 ---------- Previous post was made at 17:23 ----------

He's paying'but I will offer a contrabution (we all have to eat)

He has said he will not leave till its right

The solar has been working at full power for about three quarters of the time(no sun) I think its not worth the hassel with the fits

No I havent asked about the structural survey, but a couple of my friends have had bigger PV systems on their barns with structural survey done and they did not need anything doing,so I am not that worried
Newman,

The pics do not work for me so I have tried to enable them by quoting your post, not sure if it will work.

---------- Post Auto-Merged at 18:19 ---------- Previous post was made at 18:19 ----------

Nope!

Sorry the pics don't work.

 
Now about this one way street,could you please tell me what volt drop I will get on SWA 25mm2 3 core on a run of 54meters ,253v at the CU with .4ohms grid impedance, generating 17.4amps

---------- Post Auto-Merged at 18:23 ---------- Previous post was made at 18:19 ----------

Newman,The pics do not work for me so I have tried to enable them by quoting your post, not sure if it will work.

---------- Post Auto-Merged at 18:19 ---------- Previous post was made at 18:19 ----------

Nope!

Sorry the pics don't work.
Strange, they open for me on the thread at this end, I could email them to you

 
manator,

manator,

MANATOR

your help is required.

I just hope this isnt one of those things where if you say his name 3 times and turn around................

 
It looks like its a bit high up; unless thats the angle.........
Yes its high up about

10 foot

---------- Post Auto-Merged at 20:14 ---------- Previous post was made at 20:13 ----------

Thanks for the pics NewmanThe SMA inverter looks like its mounted on wood?

Check this SMA tech doc out.....

http://files.sma.de/dl/7418/HolzUnt-UEN082610.pdf

---------- Post Auto-Merged at 19:58 ---------- Previous post was made at 19:53 ----------

1.785 volts

So The Inverter will need to be running at 253 + 1.785 Volts on the AC side
Yes its mounted on wood..........bit worried now

 
newman,

How can you (anyone) adequately maintain this equipment safely when it is 10 feet from finished floor level, without any access equipment.

Considering that the first rule of the hierarchy of control for the working at height regulations is don't do it!

Thus the install does not comply with CDM regulations, so another reason that the installer has mucked up.

 
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