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Thank you for the great forum, Safe Driving over the weekend. Sincerely Jason

Peter Topp

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Peter Topp last won the day on December 29 2019

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  1. Hi Cal I understand where you are coming from. I have a wife that knows nothing about electrical systems and wants everything essential to work during load shedding. For the things to work as you have mentioned unfortunately there is no simple quick fix. I will only suggest the route to take as you have no knowledge on the systems. 1. Make a list of all the essentials needed during load shedding or power outage. As stated in earlier post your gate motor, alarm, and garage door open should have battery backup which should be sufficient. 2. That does not leave you with a whole lot of essentials. I would suggest you add or split 1 separate plug circuit to run a microwave which can cook food and boil water etc which runs at 1kw or less. You can also run a tv, computer, dstv, phone charger and modem together from this circuit (not to be used for kettle or any other heating devices). Add a separate circuit for lights. All of these together should add up to less than 3kw. 3. For the above you would need a 3kw off grid inverter with backup batteries. The amount of batteries depend on the time needed and load. ( 2 x 200ahr 12v batteries for a 24v system) The db board would need to be split for this to make it easy to use. This would have to be done by a qualified electrician. The system can be wired in such a way that the system automatically switches over during load shedding. 4. You can get quotes from different companies. I cannot suggest any as I am not from PE. 5. You could also run off a generator which is less expensive however this would be not as simple to use and will not be automatic switchover. I hope this will help you.
  2. Hi If I am correct you have 2 strings in parallel of 3 pv panels in series. Each string is just over 9amps which gives you the 20amps in total. It is unlikely that the 30amp fuse will blow due to overcurrent. To my knowledge and experience with fuses the most likely cause would be the following. A fuse when it blows from overcurrent will usually fuse in the middle of the fuse wire. this can only be seen if the fuse wire can be seen eg. glass fuses. I am sure the fuse wire cannot be seen because it is a ceramic fuse. The fuse can also blow or fuse, in this case melt because of a bad contact in the fuse holder. The resistance caused by the bad contact acts as an element. The fuse wire will melt off the end of the fuse metal contact because of heat. It will be best just to replace the fuse holder and the fuse. Also check that the wires are securely fastened which can cause the same problem. I hope this info will solve your problem.
  3. Hi To my understanding the voltages do not matter on ac or dc in a trunking. Dc trunking or ac seperate trunking only. So you can put those cables in the same trunking.
  4. Hi From my experience in using fuses especially on the PV to inverter side there is a caution. Dc produces a large arc when connecting and disconnecting when the PV,s are live. If you do not open the fuse holder fast enough the arc can set the fuse holder alight (comes from personal experience). A dc circuit breaker will have a fast switching action which will limit the arc and is safer. I still use fuses but I am now more careful.
  5. Hi Before you can go ahead I think you will need to do some more homework. 1.First of all you would need to know if you want a grid tied or off grid system. Do you only want it only for load shedding etc.? 2. The power usage figures given are not complete. The system needs to be able to supply the maximum kw at any given time even if there is no load shedding unless you use a changeover switch for load shedding.eg. If you are using a electric stove and are using the oven and plates, unfortunately a 5kw inverter wont do the job. Two electric heating devices (iron, heater, aircon, geyser, microwave, stove, kettle, oven etc) which are switched on at the same will add up close to 5kw without anything else. 3. The battery capacity will depend on the time you would like use them at a specific load or average load. 4. Solar panels will depend on all the above points. Just to charge batteries or used all the time etc. 5. I do not think anyone will give you the brands and models of the equipment to be used as this is a personal choice for each person after they have identified their needs. 6. If you do not spec your system correctly it can cost you redoing the system. I do not think anyone on this forum is going to tell you exactly what and how to do your system. I do think you need to go and read many posts from this forum and it will help you in your decisions. 7. As far as the gas geyser I would consider using a forced fan smart geyser feeding the solar geyser into the gas geyser. Some new geyser adjust the heat and can take the solar geyser input. so you save on gas. Gas geysers are subject to a minimum water flow rate.
  6. This is typical when a gas geyser does not get enough water flow and it will switch off. This can be due to low mains pressure or someone else using the cold water at the same time. I have a booster pump to help with this as we had a problem with municipal supply. So if anyone wants to install a gas geyser it is advisible to check your water flow before considering to install one.
  7. Gas geysers have become more efficient lately as they now has forced fan and smart gas control so that you can set then on a specific temperature. I suppose they will be still more expensive per watt for heating however and they are great for load shedding. I think this is that is what people on this forum are most interested in and looking for an alternative to mains power because of load shedding and power outages which seems to be our lot in South Africa and will continue for some time to come.
  8. This is my experience with evac tubes.. I do not have the most efficient tubes. I know there are better ones out there. In winter and cloudy days they are useless. My wife and I also like to shower in the morning and by this time the water in the geyser has cooled to below 30 degrees and I need to use the gas geyser to heat the water. If I want to get the best out of the tubes I will have to change my habits which I am reluctant to do. I suppose the most efficient way all the time is to have a geyser that is super isolated or use gas. I use the gas geyser as this only heats the water when I need it. Gas per watt is more expensive than electricity however their are no losses as with a electric geyser that continually needs to be heated up as the water cools. Lucky for me I have combination of all 4 choices (mains, evac tubes, gas and inverter with batteries and pv panels) each which can be activated at any time except the evac tubes which are permanently in use.
  9. Hi There are many other insights if you read other posts n this section. To add to my suggestion above I would use a dc solid state relay for temp control using the existing thermostat and a normal 30amp switch to switch from dc to ac and only switch when there no direct light to avoid arching problems.
  10. Hi You can try Full Circle Solar for the inverter FCS 3Kva-VP- 3000w at R6499.00. II am almost sure it is made by Voltronic as is the RCT. As far as the batteries you could opt for two 12v Life batteries in series. You would also pay tax on an overseas order.
  11. Hi I do not have any experience in fitting dc elements however dc elements and ac elements will work the same as it a resistive load and does not change with dc if the voltage and current is the same. You do not have to change your element. This means that you have to match the output of the solar panels to a voltage of about 230v dc and a current of about 8.7amps for a 2kw element and 13amps for a 3kw element. (eg: 6 X 330w panels in series will give you about (37.2vdc x 6) 223,2dc volts and can deliver 8,9 amps ). This at optimum sunlight conditions which means you could go slightly higher.(add 1more panel to give 260vdc and 8,9amps) There is another problem which is the thermostat that is commonly used as it does not work well with dc switching. You could use the thermostat to switch a dc contactor that can handle the dc current during temperature control. You need the thermostat so that you do not boil the water or go above about 70 degrees Celsius. It has the same problem that with no sunlight it will not heat the water. You can with using the above method using an appropriate dc switch, switch from solar panels to mains when there no sunlight as you would use the same element. I have a system which uses vacuum tubes to heat my water in a normal geyser which then is fed to a gas geyser. It has also the option to be heated by electricity if I do not have gas and the tubes have not heated the water enough. I set my water temp at 50 degrees Celsius.
  12. Clinobrite does not filter out particles to 1 micron only to about 3 micron. The mesh filters are only for protection if the frp vessel sives are damaged. Changing to auto flush valves to me made a huge difference as I have 5 x frp vessels to backwash. I know what maddox looks like. I am just interested what can dissolve it as this material can be regenerated and reused and should not dissolve. I thought from the photo that the maddox might have broken up into smaller particles giving the photo the black appearance.
  13. Hi I have never heard or seen maddox (greensand) dissolving. Maddox is pretty dense material as can be felt from the weight of the material. The dark brown material is most probably iron. In the pics material looks very dark almost black. The colour of maddox is black so I was thinking it might be maddox. I also see that bottom sive is clogged up as you have mentioned and shown. If there is a lot of pressure it will break which I have experienced and I have installed 130 micron mesh filters after my FRP vessels to prevent material entering the rest of my system if this should happen. I would look into what dissolved the maddox as this does not seem normal. I would love to hear from anyone who knows what caused this problem with the Maddox.
  14. Hi Some interesting facts on my borehole capacity tests I did this morning on my property. The test was done with my existing .75kw borehole pump, stopwatch and a Elster Kent water meter. 05/02/2020 Borehole Capacity Test Test done at 20 Canberra Avenue Impala Park Boksburg Gauteng South Africa 1459 on the 05/02/2020 at starting at 07:43 am. Test done using a .75kw borehole pump, stopwatch and a Elster Kent water meter in a 165 diameter 50m deep borehole. Borehole depth: with casing 45 meters + plus 5 meters without casing. Total 50m. Some resistance from 2 X FRP Clinobrite media filters (Zeolite), 2 X 130µm mesh sediment filters and a 20mm venturi during irrigation. 1 1. Maximum pumping time at 31.8 litres per minutes (time until borehole well is empty while replenishing): 80 minutes. (03974554L 06:43 ------ 0399363 07:43) 2 2. Pumping speed during irrigation until borehole well is empty: 31.8 litres per minute or 1908 litres per hour only for 80 minutes. 3 3. Borehole well capacity without refilling: 1690 litres (1.69 cubic meters). 4 4. Borehole well filling capacity during irrigation (replenishing): 864 litres in 80 minutes. 5 5. Borehole well filling capacity (replenishing): 10.8 litres per minute or 648 litres per hour. 6 6. Time to fill borehole well from empty to full: 157 minutes (1hour 37minutes). 7 7. Steel Casing 2mm thick, inside diameter: 165mm (radius= 82.5mm). 8 8. Height of water from the bottom of the borehole well: 19.75m +1m = (V=πr²) +1 = (1.690/3.14x (0.027225)) +1 =19.75+1= 20.75 meters. Pump sits 1 meter from the bottom of the borehole. 9 9. Volume of water per meter for 19.75 meters +1 meter: 85.564L per meter. 1 10. Water table depth from surface: 50m-20.75m= 29.25 meters. Borehole Capacity Test 05022020.docx
  15. After doing more research I see there is another home assistant that is not commercially sold and it is for the DIY. The switches can all be integrated into this system. I can be run from a local server or a Raspberry Pi. I will be looking further into this. The Home Assistant in my previous post was a system that is commercially sold and professionally installed.


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