February 12, 20233 yr We have this very unique problem with an installation. Sunny Island Sunny boy combination with a lithium battery. When loadshedding starts i.e the municipality switches off the power, the Sunny Island goes into standby mode. This happens every time when loadshedding starts. Then a manual switch on from standby is done and everything runs perfectly fine. When we switch off the main breakers in the DB or even at the electricity at the meter, or any trip switch prividing power to the Sunny Island, the Sunny Island switches over to battery and runs perfectly. This also happens everytime. Sunny Island was replaced under warranty, battery was replaced under warranty. We had second opinions from electricians confirming there is no wiring issues, but still the problem persists when loadshedding kicks in. SMA confirmes the settings are 100% fine. Has any other installers had this very unique problem? Could it perhaps be in the way that the municipality switches off the grid versus a main breaker switches off the grid?
February 13, 20233 yr This may be totally dumb, (sparky;s please don't laugh) but here's my take based on the way these led light bulbs with a battery work when loadshedding takes place. These bulbs light up when the contacts are shorted, thus when loadshedding takes place there must be a short in the system for them to work when in a normal circuit and this "short" must be the windings of the eskom transformer. So maybe your inverter detects the "short" and goes to standby???? If the above is found to be hilarious, well at least I brightened up your manic Monday.😁
February 13, 20233 yr How about to add ZIEHL UFR and couple of contactors, so once the grid parameters starts to go out of the norm the installation will be automatically disconnected? https://www.victronenergy.com/accessories/ziehl-voltage-frequency-sensitive-relay-ufr1001e Or, maybe just a simple automatic transfer switch will do the job too.
February 13, 20233 yr When a transformer is switched off on its primary side, inductive kick produces a voltage spike in the secondary that can damage insulation and connected loads.The question would be at the start of ls do they switch the primary side of the transformer or the secondary side. If they switch the primary side off then you will get inductive kick on the secondary side and all loads including the inverter might see it as overvoltage.
February 13, 20233 yr 12 hours ago, Thunderdolt said: This may be totally dumb, (sparky;s please don't laugh) but here's my take based on the way these led light bulbs with a battery work when loadshedding takes place. These bulbs light up when the contacts are shorted, thus when loadshedding takes place there must be a short in the system for them to work when in a normal circuit and this "short" must be the windings of the eskom transformer. So maybe your inverter detects the "short" and goes to standby???? If the above is found to be hilarious, well at least I brightened up your manic Monday.😁 If you are referring to emergency light bulbs with their own internal battery, this is not how they work. They turn on, even thought Eskom is not available, through finding a complete electrical circuit through other devices connected on that same internal electrical circuit, no "short" required.
February 14, 20233 yr 16 hours ago, I84RiS said: If you are referring to emergency light bulbs with their own internal battery, this is not how they work. They turn on, even thought Eskom is not available, through finding a complete electrical circuit through other devices connected on that same internal electrical circuit, no "short" required. Surely the only thing that completes a domestic lighting circuit is the 220V winding in the eskom transformer? But if I am wrong can you point me to, or send a drawing of a lighting circuit that is complete in some other way. I am not being funny, I am truly curious as to how those bulbs know that Eskom is no longer present.
February 14, 20233 yr 17 hours ago, I84RiS said: If you are referring to emergency light bulbs with their own internal battery, this is not how they work. They turn on, even thought Eskom is not available, through finding a complete electrical circuit through other devices connected on that same internal electrical circuit, no "short" required. To the uneducated likes of me, that sounds like a short. I'm interested in this because there is one light socket where I installed one of these bulbs, and it ALWAYS burns. Which is the other side of the coin. A regular bulb in the same fittting works fine.
February 14, 20233 yr 5 hours ago, Bobster. said: To the uneducated likes of me, that sounds like a short. I'm interested in this because there is one light socket where I installed one of these bulbs, and it ALWAYS burns. Which is the other side of the coin. A regular bulb in the same fittting works fine. If it burns permanently it is able to find a completed electrical circuit through the exisiting wiring feeding the fixture the bulp is plugged into. This explains it nicely. https://youtu.be/EDwc4pL0TdI Edited February 14, 20233 yr by I84RiS
February 14, 20233 yr Remember that if you loose Eskom power, there are many, many household items that each have a finite impedance (resistance) still connected across Live & Neutral. These bulbs, at loss of AC power, will use battery power to enable a small impedance measuring circuit. If the light switch is off, it will see a high impedance and will remain off. However, if the light switch is on, or turned on a bit later during load shedding, it will see a lowish impedance as a result of all those other household items (clock radio, TV, electronic microwave, etc. and it will now switch on the LED driver circuit. You should be able to test this: Make sure that ALL lights on a particular lights circuit breaker are switched off. Then also switch off that particular circuit breaker. Doing so, your battery backed-up LED should remain off, irrespective of the switch position. The reason being, that you isolated the light circuit from the rest of your house wiring. There is now no pathway for the light to register the impedance of your wall-socket powered devices. On normal LED lights (i.e. not battery backed-up devices) you often notice them being "on" albeit very dim, with the switch off. Alternatively, and more irritating, is that they might flicker, again with the switch off. The reason is capacitive coupling between various power carrying wires in close proximity in the same conduit. The LED lights can immit light at extremely low forward current. To fix this problem, one needs to connect a bipolar high voltage capacitor across the light fitting terminals. Usually something like a 100nF or 220nF 250VAC capacitor will do. The capacitor will bleed the current away. Being a reactive (and not resistive) element, it will change your power factor, but will not consume real power. Just make sure that the capacitor rated voltage is high, ideally use a so-called X-rated capacitor that is designed to sit across the mains. These need to meet certain standards for being self-healing and fire safe.
February 14, 20233 yr Silver Shadow, to your dark island, rainy girl problem... There are so many different ways people connect their inverters that it is difficult to say. Even with a wiring diagram or physical inspection it is sometimes possible to miss some leaky item that can have strange effects. If I was in your position I would perform a very simple test. Connect something like a 40W or 60W incandescent light bulb across the AC input of the inverter. When Eskom goes south, the light bulb will have a fairly low resistance to bleed away any possible charge that might be present. Don't use a LED for this, they will not necessarily give enough load. It's a long shot, but it is relatively easy to do.
February 14, 20233 yr This post was recognized by Energy-Jason! Modina was awarded the badge 'Helpful' and 10 points. Silver Shadow, one more thing, I know you said the electrician checked everything but still, just make sure that your inverter is properly earthed. It might be good to measure any potential AC voltage difference between inverter earth and the DB panel earth. If that inverter is somehow floating then that could explain a lot of things.
February 15, 20233 yr Author Thank you everyone for the responses. Modina, I will go and check that out.
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