EG4 6500EX-48 grid draw increases as PV starts up in the morning

Texican said:

what do you make of this ??
load is 678w
pv is 190w
and no drain on the batts or the grid
so what is powering the load ? magic juice ?
this is in SBU mode with 2 lv6548 and eg4 batts
View attachment 142216

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You shouldn’t ask questions like this, just be grateful for no draw from the batteries…?

There can be timing “inconsistencies” between data received from the inverter and data received from the battery. I’ve seen these types of inconsistencies in my environment. Inverter data refresh in my case is much slower than the battery (smart shunt).

What do you use to monitor your batteries?

w8dev said:

You shouldn’t ask questions like this, just be grateful for no draw from the batteries…?

There can be timing “inconsistencies” between data received from the inverter and data received from the battery. I’ve seen these types of inconsistencies in my environment. Inverter data refresh in my case is much slower than the battery (smart shunt).

What do you use to monitor your batteries?

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I just monitor the batts via Solar Assistant/Home Assistant

Texican said:

I just monitor the batts via Solar Assistant/Home Assistant

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So are you using the emulated BMS in SA?

I have battery type as USER
and comms as USB Narada RS485
is that what you meant ?

should I switch batt type to eg4, I dont think that was an option when I set this up ?

Texican said:

I have battery type as USER
and comms as USB Narada RS485
is that what you meant ?

should I switch batt type to eg4, I dont think that was an option when I set this up ?

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I mean in Solar Assistant. Under the Config tab -> battery section. What do you have selected?

w8dev said:

I mean in Solar Assistant. Under the Config tab -> battery section. What do you have selected?

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Ok, so I see that USB Narada RS485 is an option in SA. What batteries do you have?

6 x eg4 lifepower

Texican said:

6 x eg4 lifepower

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I guess you could switch the inverter to EG4 and plug your batteries into the inverter, then change SA to “use inverter values” as you would have coms set up between the batteries and inverter.

After looking at the SA site for the direct EG4 battery connections, your using the right protocol, so I would assume there might just be a slow refresh rate (or bad communication between SA and the batteries).

Solar Assistant is the Norton Anti-virus of the solar world. Delete it and your life gets better immediately.

PreppenWolf said:

Solar Assistant is the Norton Anti-virus of the solar world. Delete it and your life gets better immediately.

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WatchPower yes, but not Solar Assistant. It’s a great tool to give you much better insight into your system than the tiny little displays on your inverters where you can’t even see multiple data points on a single screen.

In fact, when I tried to install WatchPower on my windows computer (using the CD that came with the inverter), my AV wouldn’t let me install it because it said the file contained a Trojan.

timselectric said:

If it's reporting correctly with the Victron shunt.
The problem was with the BMS.
SOH is a useless number anyway. It's a best guess from something that is terrible at guessing.

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Tim, you're missing the point. I checked the BMS's with the BMS Test software and everything was fine. There is no erroneous data coming out of the BMS's. When the batteries were hooked up directly to Solar Assistant, Solar Assistant was taking the individual results of SOC and SOH from each battery and averaging them(with its own internal calculations) to give a total SOC which was always wrong, with the missing SOH percentage points showing up as an overcharge in SOC percentage points. Batteries Don't charge to a percentage greater than 100% but Solar Assistant sure thinks they do. It is a flaw in the mathematics and I did report it to Pierre. I wouldn't trust any of the battery metrics from Solar Assistant until this is corrected as it makes it impossible believe what it's reporting. The Smart Shunt now reports the correct SOC to Solar Assistant and I can tell you that it's far different than what Solar Assistant was calculating and reporting.

"The Smart Shunt now reports the correct SOC to Solar Assistant" I would like to set this up, how is it done?.

shopman said:

Tim, you're missing the point. I checked the BMS's with the BMS Test software and everything was fine. There is no erroneous data coming out of the BMS's. When the batteries were hooked up directly to Solar Assistant, Solar Assistant was taking the individual results of SOC and SOH from each battery and averaging them(with its own internal calculations) to give a total SOC which was always wrong, with the missing SOH percentage points showing up as an overcharge in SOC percentage points. Batteries Don't charge to a percentage greater than 100% but Solar Assistant sure thinks they do. It is a flaw in the mathematics and I did report it to Pierre. I wouldn't trust any of the battery metrics from Solar Assistant until this is corrected as it makes it impossible believe what it's reporting. The Smart Shunt now reports the correct SOC to Solar Assistant and I can tell you that it's far different than what Solar Assistant was calculating and reporting.

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That's definitely a problem. SOH has nothing to do with SOC. Not sure why it would be included in any calculations. Not even sure why there would be any calculations needed. Unless it's using the Emulated BMS. But I wouldn't trust a BMS for either, anyway.
I also use the Smart Shunt. As it's the most accurate way to track SOC. And works perfectly with Solar Assistant. Which is why I purchased it.

bones1 said:

"The Smart Shunt now reports the correct SOC to Solar Assistant" I would like to set this up, how is it done?.

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VE direct to USB cable and select "USB VE. Direct" in Solar Assistant battery settings.

I checked my grid draw this evening and I'm pulling 84W per unit. I'm running SBU mode. It's raining here the next 24hrs but I'll check the draw in the morning and then again Sunday when the sun is back out to see what it does.

Because of all these AC-in inconsistency reports in the forum, I've installed contactors in my AC-in phase wires which I can control with WiFi smart relays (tasmota flashed). I publish all the data via SolarAssistants MQTT gateway to my smart home system (OpenHAB) anyway, so I can control via an OpenHAB rule if and when I would like to close the AC-in contactors (only if batteries are below 10% SOC and still no solar charging). With this implementation I have complete control about AC-in usage (as a side effect, it was relatively easy to implement a complete solar emergency shutdown which taken the AC-in also into account)

Off topic: Here are some details about the whole solar emergency circuit, in case anyone is interested:
Beside the AC-in contactors, I've installed two 600A battery relays to disconnect the battery racks and also disconnect the PV strings via already exisitng Tigo TS4-A-2F modules (PVRSS) in case of an emergency. Emergency will happen if either one of two emergency buttons (inside and outside) were hit or one of the smoke detectors (https://www.amazon.com/gp/product/B00PC5SNIE) located over the inverters are signaling alarm via smoke detector realy (https://www.amazon.com/gp/product/B00HQNPOHI)). Because all 3 possible energy sources (AC-in, batt, PV) will be disconnected in case of an emergency, all the inverters will completely shutdown.

The additional invest is not as bad as it sounds, the cost for a 3-pole AC 110A contactor is about $55 (https://www.amazon.com/gp/product/B09F5Z9D2H), and a 600A 60VDC contactor is about $65 (https://www.amazon.com/gp/product/B0969GJGPC). The Tigo PVRSS system is able to remote disconnect the PV on a module level base (every PV panel will be disconnected form any other) and this is the priciest part of the emergency shutdown system. For every 2 PV panels, one Tigo TS4-A-2F is required which is mounted on the PV panel (about $50). To control all installed TS4-A-2F modules, one Tigo transmitter unit is required. It communicates via PLC (Power Line Communication, contactless via current transformer), so no additional wiring beside the existing PV+ and PV- is required. The controller can handle up to 10 strings with a max. of 100Amps per CT (2 CT's are possible for one controller). Some states/counties already require module level rapid shutdown system (PVRSS) anyway to get a solar building permission! The controller is about $180 for the two CT version.

I'm aware that this sounds a bit over-engineered but this let me sleep much better...

Again, set to OSO in option 16, solar charging only bringing in 1300 watts, and in SUB mode with no loads attached I am pulling 450-500 watts from the utility. Why is it pulling 500w from the utility when charging the batteries from solar only and zero loads are running?.
I switched to SBU mode and the grid draw disappeared, everything was normal.

bones1 said:

Again, set to OSO in option 16, solar charging only bringing in 1300 watts, and in SUB mode with no loads attached I am pulling 450-500 watts from the utility. Why is it pulling 500w from the utility when charging the batteries from solar only and zero loads are running?.
I switched to SBU mode and the grid draw disappeared, everything was normal.

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This is normal for SUB mode.
It guarantees no export. Usually 300 to 500 watts.
This is a buffer to give the inverter and SCC time to react to changing loads.

Thanks for the reply, Tim. So best to not use SUB mode if you are trying to reduce your electric bill I suppose. Good to know the equipment is functioning normally.

timselectric said:

This is normal for SUB mode.
It guarantees no export. Usually 300 to 500 watts.
This is a buffer to give the inverter and SCC time to react to changing loads.

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That's an very interesting statement about "export".

For my understanding, the EG4-6500EX-48 is a pure off-grid inverter which is not able to export anyway. From the electrical theory point of view, an exporting inverter is a current-source which does NOT create it's own sine wave, instead it just pushing current to the grid which will result in automatically create the sine wave (follow the grid provided waveform). An off-grid inverter is a voltage-source which generates it's sine wave by itself. So these are two completely different use cases (maybe achieved with the same inverter hardware with intelligent logic to switch between these two modes - some call it hybrid).

I found the similar inverter (a different re-branded Voltronic) from a company called Phocos (PSW-H series). I found the following statements in the manual (https://www.solar-electric.com/lib/wind-sun/Phocos_PSW-H_Series_manual.pdf).

page 2: "Grid injection of excess energy possible where it is legal, with or without a connected battery. Accidental injection is prevented by requirement of a PIN code for activation"

page 4: "The Grid Injection functionality allows feeding any excess power into the grid. If there is excess PV power beyond what is utilized by the load and for battery charging, this power can be fed into the public grid to take advantage of net metering or feed-in tariffs. In this way all the PV power can be used even if the battery is full, and the loads do not require all the available PV power. Feeding into the grid may be prohibited in some areas so this function is locked by a PIN code to avoid accidental grid injection."

page 28: There is a program 08 (which does not exists in the EG4) which is called "Solar power feed-in into grid" with default "Disabled".


So I assume, that the EG4 inverter would be also technically able to feed energy back to the grid and it's just disabled in the EG4 firmware. That's maybe the reason why you've written "It guarantees no export when consuming between 300-500 Watts"?

bones1 said:

Thanks for the reply, Tim. So best to not use SUB mode if you are trying to reduce your electric bill I suppose. Good to know the equipment is functioning normally.

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In my opinion
SUB mode is only good for a person who doesn't want a big enough battery. It's great for lowering your electric bill during the day. But it's not a very efficient mode.
Which is why I stopped using it once my battery arrived.

fmeili1 said:

That's an very interesting statement about "export".

For my understanding, the EG4-6500EX-48 is a pure off-grid inverter which is not able to export anyway. From the electrical theory point of view, an exporting inverter is a current-source which does NOT create it's own sine wave, instead it just pushing current to the grid which will result in automatically create the sine wave (follow the grid provided waveform). An off-grid inverter is a voltage-source which generates it's sine wave by itself. So these are two completely different use cases (maybe achieved with the same inverter hardware with intelligent logic to switch between these two modes - some call it hybrid).

I found the similar inverter (a different re-branded Voltronic) from a company called Phocos (PSW-H series). I found the following statements in the manual (https://www.solar-electric.com/lib/wind-sun/Phocos_PSW-H_Series_manual.pdf).

page 2: "Grid injection of excess energy possible where it is legal, with or without a connected battery. Accidental injection is prevented by requirement of a PIN code for activation"

page 4: "The Grid Injection functionality allows feeding any excess power into the grid. If there is excess PV power beyond what is utilized by the load and for battery charging, this power can be fed into the public grid to take advantage of net metering or feed-in tariffs. In this way all the PV power can be used even if the battery is full, and the loads do not require all the available PV power. Feeding into the grid may be prohibited in some areas so this function is locked by a PIN code to avoid accidental grid injection."

page 28: There is a program 08 (which does not exists in the EG4) which is called "Solar power feed-in into grid" with default "Disabled".
View attachment 142920

So I assume, that the EG4 inverter would be also technically able to feed energy back to the grid and it's just disabled in the EG4 firmware. That's maybe the reason why you've written "It guarantees no export when consuming between 300-500 Watts"?

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I wasn't aware of that being an option on other versions of these models. But it makes sense.
My statement was based on how my Growatts (also made by Voltronics) work, in SUB mode.
In the simplest terms, it's coupled to the grid. Just like a grid-tied inverter.