So now I have a solar PV system how do I make the most of it???

Martyn1981

zeupater wrote: »

.... I guess the answer must be the voltage (as most had volts before pv) and it crossed the road, as is usual, to get to the other side (where the houses are !) ....

How did it cross the road ? ... well that's simple ... either in underground conduit or via overhead cables ....

Z, I hope I'm not dragging you down to my level. If so, then there's no hope, and civilization as we know it, is doomed!

Mart.

EricMears

Martyn1981 wrote: »

Be patient here with me, but can cable upgrades/sizing and local transformers be used (I appreciate at a cost) to bring voltages down. If not to 230V, then at least closer to the mark. Should these issues be addressed anyway, or is it widely accepted/approved to be running near the 253V limit?

The class of device I mentioned earlier is just that :"a local transformer to bring voltages down". BUT (imho) the cost of the device(s) is far greater than justified by likely benefit.

All local substations are dropping voltage to somewhere near 230v. Only slight snag is that many of them have never been adjusted (indeed perhaps cannot be) since the target was 240v.

Ich_2

All local substations are dropping voltage to somewhere near 230v. Only slight snag is that many of them have never been adjusted (indeed perhaps cannot be) since the target was 240v

We can manually adjust output voltage in the range +/- 5% in 2.5% steps of the nominal transformer output voltage.

In some ways the above is about right, take a DNO with 34,000 transformers, the majority of which are designed for a secondary output of 240V.
To reduce voltage to 230V on one transformer is minimum of a days work preparing and doing it for one man (if an overhead transformer it is far more). So then work out how long it would take to reduce all of them to 230V.

The national system design rules also accepted that we could/can design to an 8% volt drop between the transformer and the final customer (also a 3% volt drop is reccomended for internal wiring) so if we commision at 230V we are immediately looking to breech the -6% limit. To counter this transformers were usually commisioned in the region of 250V at the lowest load point (don't forget as load increases, voltage lowers and vica-versa). This has continued with the voltage being in the mid 240 - 250V range to ensure that customers at remote ends do not see low volts at remote circuit ends (try running a lot of gear at 216V and see what doesn't actually work).

So yes voltages can often be near the upper limit, this is a situation that is well known in the industry. If it is causing problems for customers with generation we do when alerted to it reduce voltages, if it causes low voltages elsewhere, we will deal with them.

But for the second time that is not really my point of concern! It is the fact that the PV installers are commisioning systems in this condition, that their electricians are issuing wiring certificates with out of limit voltages on them (which they should not do) and it is all being left to the customer to discover the problem and contact the DNO.

But bear in mind if the voltage measures in the range of 216.2 to 253 it is within legal limits and we would not seek to adjust it. If it is outside these we will deal with it even if it is generation that ir causing it to go outside limits

jimjames

Now got our numbers in for April and amazingly despite being the wettest month for 100 years our generation was pretty much on target at 320 kWh for a 3.01 kWp system. March was 317 kWh so we are marginally up on that. Makes you think how high the numbers would have been if we had sunny days!

Martyn1981

Jim, there are some more (disappointing) numbers on the generation thread:-

https://forums.moneysavingexpert.com/discussion/3853851

Checking the weather ahead, looks like a pretty miserable first week of May. Lousy all morning for me today, with my ESE system, then when it cleared around 2pm, it really cleared, complete blue sky, so very little reflection, only 200W or so, rather than the usual 500 to 800. Booh, bah, grump.

Mart.

nobby1963

Hi all,
As it seems to have gone a little quiet here perhaps I am asking at the wrong time but here goes anyway .....

We have an SMA 4000TL inverter and I was wondering if it was possible to monitor our pv system via the web ?

We do have a Sunny Beam at home but was wondering about when we are away from home ?

Also if anyone has the same type of system and uses Sunny Explorer - can you tell me if you have the problem where odd days do not show up their generation graphs / stats ? I have a number of days that either don`t show a daily generation graph but do show up on the monthly bar chart and a few that show a daily graph but not on monthly bar chart !
Just a niggle but I cannot understand why and have not been able to fix the problem.

Thanks in advance .....

A Devon newbie `ish

sly_dog_jonah

nobby1963 wrote: »

Hi all,
As it seems to have gone a little quiet here perhaps I am asking at the wrong time but here goes anyway .....

Welcome to the solar gang nobby1963. I think this forum's gone quiet because the weather (and hence generation) has been so rubbish recently. Hopefully things will pick up soon, they can't get much worse!

Afraid I can't help with the Sunny Explorer issues you're seeing, but sure someone will be along to help soon. I'm pretty sure there is a remote monitoring solution available from SMA, but it ain't cheap. Apart from curiosity, is there any reason why you'd require remote monitoring? Are you able to remotely turn on a washing machine etc?

pwllbwdr

I have a SB3600TL and use an old netbook to log into it every 20 minutes by bluetooth and then upload the data to pvoutput.org. That means I can monitor the output of my panels from wherever I am either via a browser or on my phone (there is an android app).

A script on the netbook runs the sunny explorer software. I found the script online - let me know by PM and I will send you the link to the script.

nobby1963

Hi Jonah,
Thanks for the quick response ....
No particular need for remote monitoring just enjoy seeing how things are going.
I know that lots of systems can be monitored via the web and just thought a big company like SMA would offer the facility but I have looked for it and cant find it. I know they offer iphone apps and as I have an iphone I downloaded some but as far as I can see they are a waste of space ( unless I am missing the plot ! ).

Cheers ...Nobby.

nobby1963

Hi Paul ( ? ) / pwllbwdr,

Ok so you will have to excuse me here ...I am a one fingered typist so I struggle to keep up with replies !
Also I don`t want you to get the wrong idea about me, the computer age nearly passed me by and as long as I have been shown what to do with the thing I am fine but when it comes to scripts and uploading you are way way ahead of me I`m afraid !
I just thought that if I was able to see what I see on the Sunny Beam or Sunny Explorer that would be great.
I guess the fact that you can see you 3600 from a computer is a good sign I may be able to see mine ?

Cheers....Nobby

Hang on ....Bluetooth - that means you are at home and seeing the output I guess ?