Navitron Renewable Energy and Sustainability Forum

Announcements & News => SHOW US YOURS.... (pics of installed systems) => Topic started by: Nickel2 on September 29, 2017, 04:27:48 PM

Title: Workshop PV
Post by: Nickel2 on September 29, 2017, 04:27:48 PM
The next-door neighbour from hell has finally moved out after making my life a misery. No more vexatious litigation! No more complaints to the council about my shed that was there before she moved in. No more stupid daughter and her coterie of cretins throwing stones at my workshop windows. No more shouting and swearing - the new folks are a polite and well mannered couple.
I've had my panels for 18 months without a permanent installation, due to the above harridan, but now they are on the workshop roof. 6 x 190W Trina mono.
Brackets cut from 50 x 50 x 8mm angle aluminium.
25mm solid spacers cut from 1" aluminium round bar.
40mm x 3mm aluminium washers cut from plate with a hole-saw.
Screw-core size hole drilled through felt and roof board into 4x2 timbers.
Hole filled with 'low modulus' silicone, a dollop under the washer, then stainless coach-screws to hold it all down. Surplus goo used to form a fillet over the washer.
Fischer new old-stock from fleabay for the extrusions and clips. All fasteners are stainless 8mm.
Some pics:

The wires from the panels go in through 40mm bath-waste pipe push-in fittings, with a squished-up length of pipe insulation stuffed in either end to keep the bugs out.
After the recent competitive conversation (ahem) about connecting panels in parallel, I opted to go with the concensus and did not fit the diodes that I had previously expounded.

Each individual panel is brought into the combiner-box, where it is fused at 1.25 x Isc, then goes via a DC breaker, (salvaged from old 3ph ups's), to the commoning blocks. (8-way plated brass earth-strips). I was going to fit suppression snubbers to the switches but decided that they would only be switching Voc - V Batt worst case, so not required. Panel 1 does not go through a breaker, as it is switched directly by the o/p switch. (only managed to find 5 breakers).

The combined outputs are then fed via a double-pole 40A dc breaker, where they leave as 16sq mm equipment-wire tails that feed to the MPPT charger panel input terminals.
The MPPT charger is an 'EpEver' 4210A set to 24v at 40A max. The output connections to the battery are 16sq mm, and feed to the battery bus via a 40A midi-fuse rated to 32V working. The battery bus is a 5-way 'Henley' block. The MPPT switched load goes via another 40A midi-fuse to a temp choc-block. The fans pull air through a duct behind the heatsink if it goes over 60c.

The Battery is connected to the bus using 50sq mm wire, with all strands connected.
I have borrowed a pair of 'Armasafe batteries' for experimentation purposes until I find something more suitable.

It all seems to work ok, Now all I have to do is find some work for it to do! UG wiring back to the house only needs terminating both ends and something connecting to it.
Preliminary tests with my dehumidifier running (300W) through a 1500W APC UPS produces very little heatsink waste.

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Title: Re: Workshop PV
Post by: camillitech on September 29, 2017, 09:26:45 PM
Lovely combiner box N2, I gave this much thought some years ago as purpose built ones seem to cost an 'arm and a leg'. Having far too many tasks on the 'to do list', I just use a consumer unit the wrong way round now with suitable MCB's. Methinks yours looks much more professional though  :genuflect

Title: Re: Workshop PV
Post by: biff on September 29, 2017, 09:41:39 PM
Nice N2,
         May you have many happy productive days of leisure and ease.
  Having one like that next door was no joke. It is a bit like winning the lotto to see the back of her.

Title: Re: Workshop PV
Post by: camillitech on September 29, 2017, 09:58:13 PM
I certainly would not like to live next door to me  ;D Funny things neighbours, my sister in law 'number 1' has moved house three times during the twenty years I've known my wife and sister in law 'number 2' at least 6 times. Strange thing is they always seem to have the 'neighbour from hell' next door, methinks perhaps the problem 'lies within' as far as these two 'fruit cakes' are concerned, methinks if they lived next door to Mother Theresa they'd try her patience  :hysteria

Title: Re: Workshop PV
Post by: JohnS on September 29, 2017, 10:56:26 PM
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Puzzling choice of colours on the connection between the two batteries.

Hope no one confuses it for a ground connection.

Title: Re: Workshop PV
Post by: Nickel2 on September 29, 2017, 11:16:10 PM
The Harpie next door is one or a pair of identical twins. The two of them were probably quite pretty in their time, and were without doubt spoiled rotten by their father/mother. My observation is that they have always had what they wanted, even if it belonged to someone else. To clarify things I was forced to redeem my mortgage to obtain the title deeds to my house. To make the point about the boundary issue to her solicitor I took a day trip, (by rail), to show him with the deeds and point out the boundary and where she had moved it against my express wish and instruction. :fume
When the house appeared on the market, I called her solicitor to remind him that it is against the law to sell a property without declaring a boundary dispute.
He politely told me that he was not acting for her any more. I reckon that he realised that he was not going to make a no-win no-fee fortune out of me and told her to go elsewhere. I made a point of calling him regularly on the subject, and kept him talking as long as possible! stir:
Anyway, I still have two pieces of concrete in an envelope that were thrown at my windows tucked away for reference purposes. Plus 4 crime reports for various incidents...
The last two years have been of the annus horribilis type, with 4 heart attacks and 2 major car crashes, none of which were my fault.
When you have used a lavatory and flushed it away, you only need the window open for a short while for any unpleasantness to dissipate.
I am now breathing great lungfuls of fresh air and appreciating every one. exhappy:
Just got to get the body working properly again! :crossed

Title: Re: Workshop PV
Post by: Nickel2 on September 29, 2017, 11:28:46 PM
Ah yes, the interconnect... It was a handy bit of 16mm stranded thet I had to hand. (too lazy to get the right stuff out). The MPPT is actually positive ground, which is not such a good thing when most inverters are negative grnd.
This means that I shall not be connecting any earths to the PV system, except for the Frames on the roof, ie leave it all floating. If I accidentally forget and connect +ve grounded system to a -ve grounded system it would result in a loud blue flash, with the associated release of smoke, tears of grief, and clasping of the wallet in dismay.
So, it will all float. The AC power from the wshop to the house will be fed in as TNC, (?) unless anyone recommends differenterer.
Anyway, it's all experimental, some folk do football, I play with electricity! :P

Title: Re: Workshop PV
Post by: camillitech on September 30, 2017, 04:22:43 AM
Tis nay wonder you've had four heart attacks with that witch next door, pity her new neighbours  :crossed

Title: Re: Workshop PV
Post by: todthedog on September 30, 2017, 07:19:46 AM
Wishing you well with your new start Nick.
Having experienced one bad neighbour but nothing close to your experience.
You must feel a lightness in your step now that she has gone!

Enjoying your posts.

Title: Re: Workshop PV
Post by: rogeriko on September 30, 2017, 08:10:29 AM
Do NOT put an interconnect switch like that on the batteries. When you open that switch you are disconnecting the 24v battery reference but the charge input from the MPPT controller is still connected to the load output at the battery terminals. Put a disconnect switch on the load output circuit only. Do not disconnect the MPPT controller from the batteries ever. Always disconnect the pv first.  You are only 1 second away from making an expensive mistake.

Title: Re: Workshop PV
Post by: biff on September 30, 2017, 11:12:40 AM
I once made some nasty magic smelly smoke with a supposedly bulletproof Steca, by doing exactly that Roger,,
    Its was pocket painful. It was bulletproof but not idiot proof. It is absolutely amazing the things you find out when reading the instruction after the deed is done.
   I would have loved to have learned by other,s mistakes, :hysteria but ,,,,,,

Title: Re: Workshop PV
Post by: Nickel2 on September 30, 2017, 11:13:13 AM
Thanks Roger, I appreciate the potential danger to the equipment and have thought many times about a fail-safe method of sequential connect/disconnect switching. At the moment I have strategically placed warning labels to remind me the do and do-not re. powering the system up and down. As I am still experimenting, nothing is permanently wired away from the panel, so changes happen every other day. I do not touch anything electrical if alcohol has been taken. Before any critical moves, I tend to talk through out loud what I am going to do in the order required before doing it, then repeat the order as I do it. If I say something and it sounds wrong, it gives me a chance to reconsider. (Talking to oneself is viewed as strange by some folk, but it works for me!).

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Title: Re: Workshop PV
Post by: eabadger on September 30, 2017, 11:58:02 AM
in the case of morningstar the instructions dont say it, but after you ask they email a new page with it on!
even the new unit they sent from states has no mention of pv disconnect before batts.
their tech bloke said avoid fuses and disconectors if "codes" allowed.


Title: Re: Workshop PV
Post by: Nickel2 on September 30, 2017, 12:53:43 PM
For the purpose of the exercise, I only fitted the disconnect between the batteries to enable changes to be done without undoing the battery clamps each time, for instance trying alternative batteries without adding them in parallel with the armasafes. The 4210A manual does not have a breaker in the battery leads, only running through a fuse at the rating of the MPPT charger itself. When this system becomes a bit more solid and a good set of batts have been sourced and fitted, the disconnect will be removed completely from the thing.
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Title: Re: Workshop PV
Post by: djh on September 30, 2017, 02:07:37 PM
"If I say something and it sounds wrong, it gives me a chance to reconsider. (Talking to oneself is viewed as strange by some folk, but it works for me!)."

We used to have a teddy bear at work. It was less strange talking to him than talking to yourself, and it's amazing how many bugs he found in our computer programs.

Title: Re: Workshop PV
Post by: Mostie on September 30, 2017, 03:28:10 PM
Good stuff N2, I'm glad the Harlot from hell is gone, for some reason the Radiohead song "Burn the witch" entered my thoughts  :)

Title: Re: Workshop PV
Post by: Scruff on October 01, 2017, 12:25:06 PM
Get a DC rated Switch-Disconnect for the PV.

Isolators are off-load switches. They don't have things like magnetic blowouts, anti-weld contacts, large arc gaps and fast (1ms) disconnect operation.

Title: Re: Workshop PV
Post by: Nickel2 on October 01, 2017, 01:57:14 PM
The big switch in the combiner box is a Craig and Derricot PV DC isolator from flea-buy. The individual panels are fused to 1.25 Isc (6.5A~ 7A microwave quick-blow), then switched with Carling 'A' series DC breakers rated at 5A continous, 6.2A break, the curves were checked before buying. The fuses are there to protect the system in the event of a panel-short, (e.g. neighbours throwing lumps of concrete/deliberate sabotage etc; probably not required now, as they have moved), the DC breakers are for isolation experiments to test panel performance under various conditions.
I'm only using 2 sections of the isolator switch, one in each leg. The spec allows a breaking capacity of 30A at 500V full load, DC21B rated, 3 poles one leg, 1 pole other leg, for the 4-pole switch.
I am using 2 poles with a Voc of 45.1V, Imp 4.2A per panel at STC. Although the isolator is quite capable of handling in excess of the break current, The maximum MPPT current will not exceed 28.4A. This is set and limited by the charge controller.
The system is still experimental and not fixed. The panels are brought in separately so that I have the option of coupling them in series, (combiner not used), for possible GTI use.

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Title: Re: Workshop PV
Post by: kibi on October 02, 2017, 05:36:12 PM
It's always a pleasure to see a neat, well thought out installation. It looks like you have enjoyed putting it all together.

Title: Re: Workshop PV
Post by: Scruff on October 02, 2017, 08:48:10 PM
Sorry about the drive by pre-coffee comment N2. Aye your disconnect bares the brand of worthiness to the task. I found the C&D ABS plastic wanton and reinforced mine with bodge-o-car fiberglass. The disconnect is super fast though thanks to the preload. I much prefer turning off arrays with a blanket though.

..on the subjects of disconnects.. whistle..maybe a not-ignition protected battery isolator next to the hydrogen vent deserves an upgrade?  surrender:

Nice work, tidy.
Love the rails.

Title: Re: Workshop PV
Post by: Nickel2 on October 02, 2017, 11:12:56 PM
Scruff, you're right about the C&D plastic. I dropped the poxy thing on the bench from less than 12" and a mounting-foot half-broke off. Short growlings followed by a visit from Mr Rapid-Araldite, stuck back together before anyone noticed. whistle
The battery disconnect is only a "what can I do to temporary measure". The batts are sealed Hawker tank batteries 120Ah that I do not push anywhere near their specs, so hopefully any H2 will be re-combined before it causes a problem. Spec says charge at constant voltage of 14.25v + 0.25v, so I stick as close to 14.25 as the user-setting on the MPPT goes. Spec says float (where applicable) is 13.75, so I stick as close to that as possible.
The batts are from 2005, but still hold a reasonable charge considering they are ex-MOD. I'd have a stack of them if I could afford it! Everyone I know that has them say they last for ever. If the squaddies can't ruin them, I'd have to make a supreme effort to do so.
To you Sir 500-600 new. Second-hand 3-year old, 300. Thankyou, I'll have eight please!

Title: Re: Workshop PV
Post by: Scruff on October 04, 2017, 01:12:28 PM
in the case of morningstar the instructions dont say it, but after you ask they email a new page with it on!
even the new unit they sent from states has no mention of pv disconnect before batts.

MorningStar MPPT Operators manual page 29 "Power Up, Power Down"

Sad time of year for solar, I'm expecting my daily gain to drop off a cliff by the end of the month so I'm about to renew my accessory belt tensioner for improved diesel electron extraction. I'll be one month deep cyling from here to March.

If yer into smelly batteries you can get an awful lot more golf carts and not have to be gentle with them for less cost than ex-service AGM. Mine have never dissappointed me.

Title: Re: Workshop PV
Post by: eabadger on October 04, 2017, 06:16:52 PM
i asked and this is what they said;

Hi Steve,

The proper power down procedure is on page 33 of the latest manual. The same process should be followed for any resets as well. However in your case simply saving an IP change should not have caused a reset as only the server portion of the controller would reset

when they sent a new one i checked manual and no page 33, so they emailed me it!

Title: Re: Workshop PV
Post by: biff on October 05, 2017, 10:01:06 AM
Nice neat job N2,
                 I am involved in a similar kind of program at the moment but nothing as professional as your set-up.
  Taking the panels connections inside also gives you scope for comparing notes on their individual panel outputs.  Neat!

Title: Re: Workshop PV
Post by: Nickel2 on October 05, 2017, 11:09:15 AM
Cheers Biff. I have done equipment-wiring most of my life in a wide variety of areas, so my wiring is my signature. (but a lot tidier) As an experimental station, it will give me the opportunity to study the difference between panel voltages in sunshine and shade:
I want to find out if the MPPT unit gains or loses any power by forcing the shaded panels to work at the same voltage as the sunlit panels, away from their optimum operating point on their curves at a given irradiance.
It will also enable me to make a plot of power generated against power used on a day to night basis, and thence derive battery capacity empirically, rather than by rule of thumb or fag-packet calculation.
There is a very reliable grid source to my house, and like a lot of 'garden-shed inventors' I just like experimenting.  :)

Title: Re: Workshop PV
Post by: Nickel2 on October 15, 2017, 06:00:33 PM
We were promised all-day sunshine today, but my area didn't get out of the mist until gone 2 pm. When it did clear, I plugged the PC into the inverter output and watched the watts adding up.
The first few days were between 300-700 Watt-hours, peaking at 840.  :P
Today was my first full kilowatt produced and used  exhappy:
The batteries are probably over ten years old and struggle to hold a decent charge, but are good enough to supply 24V DC to operate the MPPT.
Just got to find a suitable set of batteries now...

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Title: Re: Workshop PV
Post by: biff on October 15, 2017, 06:52:39 PM
The satisfaction is immense N2,
                      Maybe you will go for a set of 48v forflifts and parallel the 24s. Then later if you decide to go up the volatge, you can configure in series. There is some poke in a 48c x 800ah,
   You might get the liking for this electricity generating  ;D and save money at the same time.
  Then you might consider a small horizontal,gas driven Changfa,water cooled to drive a pmg,  Tres quiet, and Tres economical, built by yourself in your own workshop. To throw out 1kw +  for 10 cents an hour. Who knows, you might even decide to opt off grid ;D

Title: Re: Workshop PV
Post by: Tiff on October 15, 2017, 07:10:33 PM

Sorry Biff, I have to ask, what is a "gas driven Changfa" ?

Title: Re: Workshop PV
Post by: biff on October 15, 2017, 08:18:34 PM
Well a changfa is normally a diesel powered Chinese horizontal engine,
                       It is a really old design and the engine is found all over the world, You get them small and large , They are a long stroke and have an open vented water tank on top, a bit like the early Blackstones but much lighter. They have been around for decades but are now enjoying a comeback being fitted to small tractors in eastern Europe and Russia. They are very common in the US and used for driving saw mills and generators.. The gas converted one runs very quiet. They have a slow rpm and would be ideal for driving a pmg ;D.
     I researched them years ago with the intention of getting one and almost succeeded but had to settle for a Yanmar clone.There are dozens and dozens of U dube sites dedicated to these engines. They are still produced with even newer models and the older one with a proper rad. The never seem to wear out. I got a strong suspicion that they had a lot to do with the Ho Che Minh Road. They also ran on wood gas. If you google "Chinese Changfa engine" You will see what I mean.
    I was getting carried away there. :hysteria
  There is one for sale on fleabay but under a different name, ( Kukie) It is stuck at 250.00 with one bid. Unused but sitting stored for 4 years.

Title: Re: Workshop PV
Post by: Nickel2 on October 27, 2017, 06:16:59 PM
Sunshine all day, 1.17 kWh. It would have been more, but I went out in the afternoon, so when the battery got to 100%, it went into float and didn't use all of the power available. If I'd stayed in and used the power, I reckon it would easily have been double.
The morning had me sitting watching the power-level grow from zero to max, between early morning tree-shadows. It's an odd feeling; a frisson of excitement similar to watching your winning bid on flea-buy!
Peak was 455W, with not all panels out of shade.
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I now have to learn how to manage my new-found power!
Batteries, hmmm...

Title: Re: Workshop PV
Post by: Nickel2 on February 06, 2018, 05:13:54 PM
A glorious day today, 10% cloud cover, 3*c, light wind.
I've been experimenting to see how much power I can wring from the panels. When the sun rose it topped up the battery from last night's drain.
When I rose, the battery was nearly full, so I put the PC onto the PV supply in the house. As the power increased I added the monitor (CRT) to the load. I couldn't find any easily accessible small loads to add, so went into the wshop, plugged in the oil-filled radiator, then ran back into the house to watch the MPPT control-panel readings.
To my great delight and surprise the system was producing, (as near as makes no odds), 800W! Sat and watched for a while then out to the wshop to see if anything had caught fire.
Both the MPPT and the inverter heat-sinks were only a few degrees above the room ambient temperature. Then a cloud came along and spoiled it, so I unplugged the heater, leaving just monitor and PC running. Shortly afterwards I had to go out, so the PC was left to go to sleep.
The lesson from this power-use experiment shows the system to be capable of feeding a substantial load.
The battery-bus has to be loaded sufficiently hard to drop below maximum boost voltage, but still keep it above 26V. It then presents a low enough impedance to the MPPT to operate as designed.
My power generated and used today = 1.42kWh. If I had kept running backwards and forwards, switching stuff on and off, it would have been higher.

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Recently I have been adding filtering to stop radiated and conducted switching noise from the inverter causing problems. My short-wave long wire runs over the top of the wshop, so picks up all the hash from the inverter. Filtering has cut this problem to the point where I can listen to distant foreign stations with only slight interference. When I have finished designing and fitting an inductive filter to the DC input, I expect it to be all but gone.

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Title: Re: Workshop PV
Post by: Nickel2 on February 24, 2018, 08:41:57 PM
Another glorious day!
Batteries fully charged after 50% DOD load-cycling exercise last night.
Outside temp no higher than 4c all day, clear blue sky.
By 11:00 the batteries were fully charged and went to float, and the GUI software showed 1 kWh generated. I applied the 400W oil-filled radiator as a load, then sat and watched the voltages stabilise. At 12:00 went outside to wshop and 'felt' the electronics. The MPPT was steady at 20c, the STI 1000 inverter was still below skin temperature.
Regular checks were carried out, then the load was increased by switching the PC and monitor on to the inv O/P, taking about 650W continuous power.
After an hour, out to the wshop. Room temp was 15c; everything was felt again. The inverter was at skin temperature, the MPPT still low, at high twenties, all the cabling and switches were at room temp, even at 25A.
Regular checks carried out until the sun went behind next door's chimney, then the load was reduced to maintain battery volts.

Some pics:

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From the figures displayed in the software, currents and voltages were referenced to the manufacturers data sheet.

The voltage vs current graph showed indicated an insolation of very roughly 600W per sq metre.

When this is multiplied by 6 panels, (6.75 sq M), it gives 4500W insolation over the total area.

Divide 4500 by 600 gives 14.8% efficiency; the data sheet gives 14.9%, so panels are working up to scratch.

Tomorrow is slated to be another cold, bright day, so I expect a repeat performance.

The oil-filled radiator has proved it's worth. By being placed in the coldest easterly room downstairs, (dining room), the back of the house stayed warmer for longer, so that the boiler fired up less frequently than the day before, so lower gas use.

Total production for the day was 3.91kWh. If I keep a closer eye on the system tomorrow I may get 4kWh by juggling loads through the day.

Title: Re: Workshop PV
Post by: biff on February 24, 2018, 09:58:24 PM
 :crossed  A shed is a happy place,
                              A shed with PV powered tools is even better. ;D

Title: Re: Workshop PV
Post by: Nickel2 on February 24, 2018, 11:08:22 PM
Biff, my shed is indeed a happy place! I had a couple of pals over swilling tea this afternoon, and they seemed to like it in the wshop. (Probably the free tea). I'm happy with it as long as it stays reliable; it is another of my toys where the money would have been better spent putting new windows in the house whistle
Anyway, while I'm out in the workshop getting construction therapy, the house is being kept warm by the sun ;D
At the moment I'm in the process of building a pair of opposite polarity Van de Graaff generators, should be capable of making some nice big 18" sparks. (If you don't hear from me for a while, you'll know what's happened, but hopefully not). 

Title: Re: Workshop PV
Post by: biff on February 25, 2018, 10:01:29 AM
I am looking forward to some pics N2,
                                     My 12v battery charger plan has taken a change of direction and now sports a pair of stealth wings and a bigger more powerful lawnmower engine.( a full 101cc job) I removed the exhaust and added some Guinness to the mix. The surge in power is much more noticeable.I have painted it yellow with black stripes because I don,t want it mistaken for a drone. Soon I will soon be able to show you a pic of the ordinary original 12v charger complete with pull cord for starting and a switch for stopping.

Title: Re: Workshop PV
Post by: Nickel2 on February 25, 2018, 06:51:05 PM
4.080 kWh today!   ;D  exhappy:  It has been perfect; clear-blue sky and 4*c all day. Probably not much compared to the bigger systems, but for my 1.14 kW's-worth I reckon pretty good. Still a month to the spring equinox, when my panels are optimised for.

Biff, - A pic of 'The Twins' (Castor and Pollux) under construction:-

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Soon my power will be complete! heh-heh-heh!

Title: Re: Workshop PV
Post by: Nickel2 on June 15, 2020, 03:55:21 PM
This morning, I find myself in a state of Deep Joy and Great Happiness!
  ;D ;D ;D
When the dreadful woman cleared off, her parting shot was to plant a fast-growing holly tree exactly due south of my panels, 10 feet away.
 >:( >:( >:(
Being evergreen , this meant that this year they would be shadowed all year round within a couple of years, so no PV.
  :fume :fume
My new neighbours now go to the top of the card-list as favourites, They have CHOPPED IT DOWN!!!
 exhappy: exhappy: exhappy:
How can I suitably express my newfound love and admiration for these people, without offering him cash, or her another baby?
It is however overcast at the mo, so midday output sits at about 35W.

Title: Re: Workshop PV
Post by: biff on June 15, 2020, 06:13:29 PM
 Good one N2.👍

Title: Re: Workshop PV
Post by: todthedog on June 27, 2020, 08:40:53 AM
Lucky you N2 cherish Good neighbours.   exhappy: