mauzilla

I have two Deye inverters, both connected to the same grid line (as per the diagram). Each inverter has its own battery bank and PV array. The inverters are not in parallel because the battery banks are different (different batteries with different BMSs, so they cannot be connected in parallel). My concern is with backfeeding. Both inverters allow for either not backfeeding, backfeeding according to the CT reading, or dumping all excess PV directly into the grid. For a single inverter setup, this is simple (I presume), but my concern here is that if I have two inverters on the same grid input (both of which have direct access to the non-essential/main DB/circuits that are not isolated to each inverter’s essential load), backfeeding from both inverters could cause problems. Specifically, I’m worried that this could fry: a) one of the inverters, b) appliances on the non-essential DB board, or c) the grid output. Here are the scenarios I believe could happen: We are drawing 2 kWh from the grid (to power the non-essential grid and possibly power consumption for each inverter). Both inverter CTs will read 2 kWh, and if both have excess electricity (let’s assume each has 2 kWh of excess PV power), they will both attempt to push out 2 kWh, essentially pushing 4 kWh onto the grid. If the inverters are both set to backfeed regardless of the CT reading, they will push excess electricity through the line, doubling the amount of electricity pushed back. As both inverters are also connected to the same line, I’m not sure if this poses any electrical issues for the other inverter or the non-essential grid. I could set one inverter to backfeed and disable the other inverter's backfeeding altogether. Although this makes sense in principle, the concern is that if someone later resets the inverter (if we sell the house, for example) or enables backfeeding on the other inverter, we might encounter the risks associated with scenarios 1 or 2. Lastly, we could disable backfeeding altogether, essentially leaving the non-essential main DB without an additional mechanism to power these devices (while the grid is online). My only logical conclusion, if this is the only option, is to move the non-essential DB to be part of the essential DB board of one of the two inverters. However, this poses an issue, as there is an obvious reason for having two inverters: we do encounter situations where the electricity usage may exceed 8 kWh. For example, if the grid is offline, the batteries themselves may not be able to sustain the draw from the entire non-essential and essential grid. Other considerations: Both inverters are set to stop backfeeding when they detect the grid is offline. However, if I am backfeeding from both inverters, this could lead to a situation where the inverters do not recognize that the grid is offline because they are both still receiving power from each other. Ultimately, the best-case scenario would be to have these inverters connected in parallel. However, this would require me to replace one of the batteries (and lithium batteries are expensive) so that it matches the other battery. This brings me to a couple of questions: If the inverters are set up in parallel, they would still be connected to the same grid line and would have a combined "essential grid," as both would need to be able to power both the office and home essential DBs. If this is the case, then both inverters should be able to backfeed, whether they are isolated or in parallel. So, I’m not sure if my concerns are valid. What “magic” occurs if both are in parallel and I have them both set to backfeed excess electricity beyond the CTs back into the grid? It seems like the result would be the same, as all excess electricity would be pushed back. I think my understanding of the flow of power is the main concern. Are the inverters simply "pushing" electricity, or are they just feeding electricity to the appliances? For example, if I’m only drawing 2 kWh from an appliance, the inverter isn’t so much "pushing" electricity as it is feeding the electricity required by the appliance (essentially opening the circuit and providing the necessary power). I’m hoping someone can clear this up for me, as we’re installing the second inverter this weekend (yes, a qualified electrician is doing it, but my scenario is not common). I would not want to have a setup that could literally blow up in my face.

Got my generator connected (5kw) to the gen port. Volts is detected, but the frequency is 0hz. We have tested from the generator to the connection at the inverter with a multimeter and the frequency is definately correct (49 - 51hz) but yet the inverter shows 0hz if I click on the generator icon. Goes without saying it does not accept the generator for charging / running the load. Anyone know what does could / would mean?

We have a Deye 8kw with a diesel 5kw generator. Although the generator does have a key start, we converted the generator to gas which needs to be primed (and gas bottle opened) so we dont want to use an automatic "start" on the generator but rather manually start it when say Eskom is off in our area and it's night time / battery SOC is too low. Has anyone else connected a generator to their DEYE inverter? I see we can enable it from the dashboard, but the documentation is a bit "light" and want to ensure we set the correct settings. It appears that the settings is mostly configured to automatically start / stop the generator or to only take power from it at certain power levels. Not wanting to fry the inverter getting some feedback from someone who has done it would be great!

I have a Sofar 6000ES with 4x Sentry / Vision 200AH Gel batteries. According to the manufacturer of the batteries, the charge voltage and full charge voltage needs to be 58.8v (or 14.7v per battery) and the overvoltage protection needs to be set to 59.2V - My batteries start charging each morning but around midday the inverter goes into a continuous "trip" where I get an error ID12 bit3, battery over current protection. I have gone through all possibilities, we have replaced cables with thicker ones, installed an DC arrestor with more than enough amperage, had it double checked, cables are perfect, and the Sofar support technician has no further "help". When the inverter "trips", power remains on, it just suspends charging with a fault, waits 60 seconds and attempts to charge again. Charging starts, amps slowly increases from 0 - 10amps but the voltage increases from 54 and you can steadily see it increase to 59.2V within seconds before the inverter "trips". It does this until about 6pm when we start working from battery power, and tomorrow morning it will start charging perfect, with volts hovering around 58.4v and amps around 5amps until a certain percentage, when it starts this loop again. I suspect that the batteries are fully charged but the SOC is misread and this causes the trip. The batteries can charge at 60amps so there is no way it's the amps that are overloaded. My experience with the Sofar inverter has been terrible, as it seems to want a perfect environment, but I also respect the safety mechanisms and thus want to find a temp solution until we go ahead and purchase lithium which my understanding has better control options for the inverter as appose to the inverter having to do all of the measurements etc. My theory is that because the battery manufacturer says 58.8v is both the charge and "full charge" voltage, once the full charge voltage increase an overload is detected (as overload protection is set to 59.2v or 14.8v per battery) and this trips the inverter until some charge has been released by the battery and it is then able to charge again. I can also confirm that the inverter seems to misread SOC sometimes jumping up or down drastically if you look at a chart. So after that lengthy introduction: When a battery is charged, which component determines the voltage of the charge, the battery or the charger / inverter charger? Is the value displayed the voltage provided by the inverter charger, or is it a reading of the current voltage of the battery, which in return determines the current state of charge How does an charger know when the battery is full? How is state of charge measured and how accurate is this measurement? An option for me is to change the chart voltage lower, to say 58.4v and leave fully charged to 58.8v with over protection to 59.2v - The problem with this is that although it charges the battery, it charges extremely slow, at only about 1-2amps, so the SOC does not increase even hours of charging. This becomes more evident when setting charge to 58.0, with the inverter almost immediately saying the SOC is 100% - with 58.4v it charges but not fast, and 58.8v it seems to be optimized, but then trips after some charge time. IF the batteries are optimally charged at 58.8v, then surely the full charge must be something else, like 59.2? What would happen if I set the full charge to 59.2 and overvoltage to 59.6v? but leave 58.8v as the charge /full charge? I'm hoping someone can advice and fill in the missing gaps I clearly have as I don't want to damage the batteries, but at this given I'm not sure how much damage is done with the "trips" so any advice would be appreciated.

We have over the last 2 years collected a little warehouse of led acid batteries through UPS's that go flat during loadshedding / interruption and stops to work after 3 - 4 full drain cycles. Some of these were our own mistakes (not knowing how these batteries work) but some unfortunately was out of our control, having said that, the result remains the same. So, I have gone ahead and purchased a battery tester, digital meters and a "trickle charger" and want to know some basics: Given what I have, what is the best way to test if a battery is a gonner? Must the battery first be charged and then tested, and if so, what does one look out for? The battery tester I got looks similar to this one: https://www.adendorff.co.za/product/mac-afric-6-12-v-battery-tester/?gclid=CjwKCAjwiY6MBhBqEiwARFSCPmg5-zSaIdDXHryalqwv9TIDwc8shKpIKwhvEoSvI-7HvXz3nIeZtxoCyKwQAvD_BwE I have successfully been able to recharge a couple of batteries that previously did not want to charge with the trickle charger. I am however not sure how to measure if it's holding full charge or if it is considered working again. Not wanting to open these 7ah batteries (I see some videos on Youtube where they have DIY techniques), will my attempts be futile in just considering the trickle charger to try and revive some of them or is it worth trying to revive them?