Muhendis

I really do like that display. It's a simple, no messing about indication of what is happening overall.

Also issued there and then in Thai embassy in London. UK seems to be a second class service in comparison.

Sods Law ????

This is an interesting thread. It reminds me of when I did some bus bar work for a Korean company. The bus bars were big and copper and were to carry around 80k Amps for an electroplating plant. Torqueing the many bolts was very specific because the copper has a certain amount of elasticity which needs to be retained for expansion-contraction purposes. Too much torque and this elasticity is lost and the joints will become loose. In order to have the right pressure between busbar surfaces, we used special spring washers under the bolts which had to be compressed but not flattened.

That would be quite normal. What I did was to place a breaker/isolator in series with each battery before the parallel connection. This is to ensure that if a battery goes faulty, ie short circuit, then current from the other battery will trip the breaker. My batteries are Gel not lithium. With lithium there should be a BMS for each of the parallel batteries which should protect the batteries from each other. It's always useful to include a breaker/isolator for maintenance for each battery.

Will there be an escape route for the water between the pipe wall and the slat wall? Or are you planning for a fish farm perhaps.

The PEA eng. was quite interested in my system and the discussion covered FiT at which point we both had a good laugh and the conversation moved on.

Snakes eat rats so bring 'em on. I have quite a few snakes so the rats go and live else where which is good for my rice storage barn. Your builders concern is probably a reflection of his (and Thai villagers generally) fear of snakes.

No they didn't Some years ago when I had a 1kM temporary supply, I shared my line with a new neighbour who paid the bill. I was on solar 100% at that time. Along came the monks and the Amphur head man and hooked into my meter for a bit of loud music. They were having a dedication party for a newly built Budhist shed just down the road from my house. The Amphur head man nominated his best village electrical engineer to do the hookup. This wonderman of electricity also swapped my live and neutral so connecting live to my ground through 1kM of 25mm² aluminium cable. The cable got warm and the meter spun round quite merrily racking up a 4k Baht bill for the day. My new neighbour didn't 'arf complain to the PEA about that so they sent a posse of engineers round to inspect the cable from the meter through the trees to my house. We had quite a discussion at the time about the ease of access to my meter and all sorts of things solar. So PEA were very much aware of the non-use of the meter (except for my neighbour). The Amphur head man was persuaded to pay that bill and promptly sent his electrician (Mr. Wonderman) to correct his mistake. Of course, this happened over a week or three so in correcting his mistake he didn't check first to see if I had already done so. You should all be ahead of me by now. I had already corrected this swapped wire problem so when the wonderman came he effectively did the same again. That was another 4k Baht bill only this time the Amphur head said it was not his problem so we had to sort it out ourselves. The upshot of this story is that PEA office were now intimately aware of my solar activities so are quite content to leave me and my rarely used meter in peace. By the way, I have had my proper supply for a few years now but I had to wait almost 8 years to get it. Such is the speed of progress.

Well spotted that man, but sometimes I do get loads of units to pay for. It depends if I need to run my mini rice mill or not. I seem to recall once last year I had a really shocking bill of almost 200 Baht ☹️

I feel so inadequate now. I've no idea when my meter man/woman comes.

I very much regret buying a Total jet washer. It would run OK for ten minutes or so then reduce power for the rest of the time and only run intermittently. I went out and bought a Bosch which has been running perfectly for the past six months or so. The Bosch was "only" 6K Baht but the best I've ever had.

I don't blame you feeling that way' I'm not from the US and I don't want to go there either.

Another thought about the panel arrangement. Although the total power capability is over 20 kW you will never get that much with panels pointing in different directions. Also the max. power from three 5kw inverters in parallel could be 15 kW but only if all inputs are at good power.

Note there is only 1 MPPT input per inverter so paralleling needs to be done with a combiner. BUT The East and West arrays could produce 7.82kw each which is above the spec. of 6kw per inverter.

Yes. As the temperature of the panels goes down their output goes up and conversely as the day goes at the time of most output the panels will be hotter and give less output. If you derate the output by 10% you will be on the conservative side of about right (this loss can be as much as 20%). The panels are characterised at 25ºC and with a 1kw sunlight simulator.

You are planning on having 4 inverters but only three PV sources. I can't think how you are going to achieve connecting three into four. If this is done by splitting each of the PV arrays into the right number of strings for each inverter then are you sure you won't be overloading the PV input maximum power? What are the input limits of the inverters?

That is true up to a point. Trouble is it doesn't take into account the loss of power from the sun in the winter when it is lower in the sky. In these circumstances the light has a bit more atmosphere to get through and is attenuated before it reaches the solar panels. To compensate for this the angle of 15º is changed by 2º to 17º thus giving better power when the sun shine is weaker.

What else could he say?

That would be about 7.8W loss for a 20M length of wire which I would guess is negligible using 2.5mm². 320V is high but I guess that's the trend. What is your MPPT range?

That depends on the length of the cable and the maximum current it's required to carry. My installation for example, generally runs at about 120v but the current from each of the two strings could be as much as 30A. My cable length is under 10M (20M there and back-again) but I use 16mm² from the combiner boxes to the charge controllers. That is probably an overkill since at 30A the losses would be about 22W If I were to use 2.5mm² the losses would be about 144W which although not alarming, is considerably higher than I would be comfortable with.

These self checkout machines are everywhere. I am finding them in airports where you can que jump by using one to get a boarding pass. All the more normal people seem to prefer the chumminess of the que. As an after thought. By using a machine the company saves money so one day they will pass on the savings to the customer?

There is no such thing as "excess generated power". The sun shines whether you make use of it or not. Just because you are not using the available electricity it produces is not a problem. The fact is, it is there if you need/want it. Imagine the situation where you have available 5kw of solar power but you have a sudden unplanned requirement for 6kw. You need to have that extra 1kw sitting there for that sudden requirement. So you need to have available as much power as you think you will need +20% for the extras you forgot in your calcs. and for future expansion. The "excess generated power" does not do any harm but just sits there enjoying the sun shine waiting for the time it's needed. In detail. With no current being taken (I=0Amps) the panel voltage (E) will go to its maximum possible and no higher (Voc) so from W=EI power (W) is zero. As current is drawn so the panel voltage will reduce. When the maximum current is reached (Imax) the power will be the sum of the current flow and the voltage of the panel at that point. In a manner of speaking, if there is no current flow then there is no power to be referred to as excess.

So what would be the result if all transportation became electric. 66% of oil is refined into petrol and diesel. Something like 4% is made into plastics like the insulation of electric cables and solar panels. The rest is split between asphalt soap/detergents ect. and loads of other products. My guess is that if no more petrol and diesel were produced, the cost of plastics and the rest would see a substantial increase. This is an interesting read over a decent cold beer, or an indecent one for that matter. https://energyeducation.ca/encyclopedia/In_a_barrel_of_oil

Things like that only happen if a complaint is made to the police. The question of why no complaint was made would have a few interesting answers methinks.