Cory

Thanks very much, very informative. This installation is already quite a few years old. Owner now wants solar and be loadshedding bulletproof. So these pump motors don’t have soft starts and will draw plenty inrush. Given the new tax rebate, it’s probably worth replacing the pump motors with variable speed drives. Then the inverter won’t break the bank.

Three phase. It’s running a few years already so I assume it’s old’ish.

This system has been running for years and now needs to to be converted for loadshedding. I’m not concerned about costing, but rather inverter sizing. Constant load on the pumps are relatively easy to assume. What I need to understand is what to size the inverter for the 3kW pump startup. Assuming only the 1kW jockey pump and one 3kW supply pump, an 8kW inverter should be fine. To spec the battery is also ok. But, will it handle the startup inrush currents?

Hi guys, Please help me to size a system for the following? Size of the inverter and the batteries, recommended brands for both. A potable water supply system on a farm, to several residential dwellings. Needs to be convertible for adding solar in the future purpose for now is to be loadshedding bulletproof. One of 1kW jockey pump runs continually to keep the system pressurized. When someone opens a tap, the jockey pump may supply sufficient pressure. When another tap opens the pressure drops and a 3kW pump starts up to feed the system. When more taps open, a next 3kW pump starts up. Two pumps will not start up simultaneously, but all can end up running simultaneously. As and when water user taps close and the pressure rises, the 3kW pumps drop out one by one, and the 1kW pump is left running permanently. Two scenarios then; all as above explained and the other one leaves out the one 3kW pump from the system entirely.

Hi guys, Please help me to size a system for the following? Size of the inverter and the batteries, recommended brands for both A potable water supply system on a farm, to several residential dwellings. Needs to be convertible for adding solar in the future purpose for now is to be loadshedding bulletproof. One of 1kW jockey pump runs continually to keep the system pressurized. When someone opens a tap, the jockey pump may supply sufficient pressure. When another tap opens the pressure drops and a 3kW pump starts up to feed the system. When more taps open, a next 3kW pump starts up. Two pumps will not start up simultaneously, but all can end up running simultaneously. As and when water user taps close and the pressure rises, the 3kW pumps drop out one by one, and the 1kW pump is left running permanently. Two scenarios then; all as above explained and the other one leaves out the one 3kW pump from the system entirely.

Has anyone heard of SmartEnergySA? https://smartenergysa.com

Thanks, did that. Things are now back to normal with one exception. The battery won’t charge beyond 90%. No idea what caused this, I have not made any setting adjustments.

Thanks. Things are back to normal with one exception. The battery won’t charge beyond 90%. No idea what caused this, I have not made any setting adjustments.

Same problem here. How did you solve yours? I have a Revov Cube system with a Synsynk 6kVA 19” rackmount inverter and with two Revov LiFePO4 batteries. I run it as a loadshedding backup and thus have no PV installed. Everything was working just fine for weeks now, and I literally did not know when loadshedding happens. Yesterday, loadshedding happened as per schedule, but lasted more than 4.5 hours. I was unaware and ran induction plates and my oven. The load is within the Sunsynk capacity. But, I accidentally drained my batteries to zero, and everything shut down. When Eskom came on, the Sunsynk started charging the batteries, but gave no power output to the house. I then switched to bypass and Eskom fed the house and Sunsynk continued to charge the batteries. Despite that the inverter charges, when I Switch to inverter, there is no power to the house. Now the batteries are idling at 90% state of charge, but it still won’t feed power to the house. Advice please?

I have a Revov Cube system with a Synsynk 6kVA 19” rackmount inverter and with two Revov LiFePO4 batteries. I run it as a loadshedding backup and thus have no PV installed. Everything was working just fine for weeks now, and I literally did not know when loadshedding happens. Yesterday, loadshedding happened as per schedule, but lasted more than 4.5 hours. I was unaware and ran induction plates and my oven. The load is within the Sunsynk capacity. But, I accidentally drained my batteries to zero, and everything shut down. When Eskom came on, the Sunsynk started charging the batteries. I then switched to bypass and Eskom fed the house and Sunsynk continued to charge the batteries. I switched back and the grid now powers the house through to inverter, as it was set up for. One exception, now the batteries do not charge up full and are idling at 90% state of charge. Advice please?

Yes, but not through inverter settings. You could do your installation as usual, with separate changeover manual switching. Personally, I have a sub-DB panel where I can select Eskom or the inverter for either essential or non essential circuits. So it gives some flexibility. See the pic of my sun-DB. What you can do is to add another three way changeover after the non-essential isolator. There you select either the essential or non-essential isolator to feed to the non-essential circuits. Note that you will under that configuration effectively select the entire installation to become “off grid” during loadshedding. If so, be sure to keep an eye on the loads as it may unexpectedly drain the battery if the sun clouds over. If you want to go smart, you can do the latter switching through a coupe of electric relays and a toggle switch. Add to that a remote network switch and control it from an app like Smart Life. But as I alluded to, your system may be sized ito capacity to isolate the non essentials during loadshedding. So be sure to not overload it.

My apology for the long winded explanation, I hope it helps. My installation is Canadian Solar, Victron Multiplus Inverter and Freedom Won storage. In terms of application I would think these things are pretty standard. Standard configuration is for essential circuits to run regardless of Eskom. Ideally, there should be sufficient capacity in both PV and battery to be off grid which of course is frightfully expensive. Hence the “Self consumption” configuration like mine, which manages important loads during grid failure. Come darkness and whilst Eskom is online (but PV is sleeping), the inverter feeds both essential and non-essential circuits, until battery reaches the preset discharge level (mine’s at 50%) then the feed for the non-essential circuits is disconnected and essential circuits only are powered. This will last until the battery fully discharges or reaches lowest state of charge setting (mine is 20%) and will then disconnect everything. Come sunlight and Eskom is online, the system will focus on charging the battery, whilst drawing on Eskom for both essential and non-essential circuits. As the battery fills up, the system will start sharing PV to total loads and battery charging. When the battery is full, the system will focus the PV to the total load and borrow from the battery. Technically, for few hours a day, the system runs “off grid”. During loadshedding, feed to non-essential circuits are disconnected, only essential is fed until the battery reaches total discharge as above. During loadshedding and sunlight, essential circuits only are fed and the battery is charged. The inverter then will balance drawdown from the PV and battery, ideally to charge the battery whilst feeding the essential circuits. If the essential circuits load exceeds the PV capacity, inverter will use max PV and draw from the battery, until the battery reaches discharge preset and all is disconnected. Note, during loadshedding, excess PV capacity will not be fed to non-essential loads. Non-essential circuits are fed only when Eskom is online. Maybe this clarifies your question?

Sorry to hear you got taken. I also ordered online, but did not pay right away. I received an email confirming my order, pending payment. I suggested that I pay COD, or issue a bank guarantee or collect personally and then pay cash. The responses were pretty amateur and I suspected a scam so I walked away. Send your collectors in to fetch your money. They must be traceable as they have transaction engines with the banks.

You’ll be surprised how little space it actually takes. My power station takes up 900mm by 2m and being Victron it’s quite bulky. I board-mounted it coz it’s a nice idea. Plenty space for more batteries and another MPPT also in that same area. Of space it right, why not raise it up, above head height. You don’t really need access. Wall hang the Sunsynk and Hubbles and MOU them either beneath or next to each other. Caution though, if you’re at all tight for space, always mount your equipment higher than the car boot/bonnet, in case there is a parking mishap. Further, think about human trafficking past your equipment, that it won’t get bashes or used as a “shelf”. If you do have floor space, you may also consider mounting everything into a 19” rack. Have a look at the Revov www to see what they do

I offered to purchase their products on condition that I pay cash, credit card or instant EFT on collection from their warehouse or office. They now simply don’t respond.