Investigation on off-grid solar energy system

 

 

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Recently, some customers have talk to us about how to use IAMMETER system in off-grid solar system. We want to do an investigate such issue below,

  1. How many customers are using off-grid solar system in IAMMETER.(if you are using off-grid solar system, please help us to click the "like" in this post. )
  2. What is the most expected feature when you monitor the off-grid solar system(such as whether there is feedin power export to grid? How to evaluate the solar/battery effect?).


we will consider do some upgrading for off-grid solar application .

What will be in upgrading depends on the replies here. Looking forward to your feedback, thanks.

 

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Hello, it would be nice if you could create an interface for the easun hybrid inverter. you can use my data for testing. please send me an email and I will send you the link to power-datacenter.com 

greetings

christoph

Hi Christoph:

You can send to this email below .(please replace # to @)

support#devicebit.com

Thanks 

Hello, it would be nice if you could create an interface for the easun hybrid inverter. you can use my data for testing. please send me an email and I will send you the link to power-datacenter.com greetingschristoph

Dear Team,

In off grid system users need to know daily solar generation that  push to the off grid battery system (DC side) & the amount of energy that comes out from battery to house. Daily, Weekly, Monthly, Yearly energy generation/consumption in house. 

I prefer the energy monitoring of the DC side because most of the off grid inverters are comes with all in one that mean one input is connected to your grid & DC side connected to battery for off grid mode(Same as above mentioned diagram).  

But the issue is when the battery is low; off grid inverter will switch over to grid then CT2 that we used to capture off grid consumption will capture grid consumption (CT1) as well. There is no way to hook this (CT2) inside the off grid inverter.

If it is DC energy monitoring with Both in & out will be really helpful.


Thanks 

  Recently, some customers have talk to us about how to use IAMMETER system in off-grid solar system.
We want to do an investigate such issue below,How many customers are using off-grid solar system in IAMMETER.(if you are using off-grid solar system, please help us to click the "like" in this post. ) What is the most expected feature when you monitor the off-grid solar system(such as whether there is feedin power export to grid? How to evaluate the solar/battery effect?).we will cons

Hi dahampathi

Thanks for your information.

Maybe we will consider introduce some DC monitor solution in IAMMETER in near future.
Then ,if you have interested in it, we will invite you as the earlier user.(we will send you the DC meter to you for free and looking forward to your further feedback)

BR

Dear Team,In off grid system users need to know daily solar generation that  push to the off grid battery system (DC side) & the amount of energy that comes out from battery to house. Daily, Weekly, Monthly, Yearly energy generation/consumption in house. I prefer the energy monitoring of the DC side because most of the off grid inverters are comes with all in one that mean one input is connected to your grid & DC side connected to battery for off grid mode(Same as above mention

Hello LaoLiu,

I'm installing PV installations for clients at Spain. Recently an avalanche of cheap inmature hybrid inverters arrived to the market.

See for example: Voltronic Axpert VMII, King, or MAX models. The same models are being sold as re-branded, like for example the "MPP solar" pip series, but the hardware of all of them is the same. 

Since they are cheap, they are being sold like candies... They have become very popular... But then the clients have a lot of problems with them, because:

-Since they are cheap, they have not AC in current sensors. So they cannot monitor the amount of energy that is beong taken from the grid. Since they have inmature firmwares, the inverters usually do weird things or keeps blocked, so the inverter start taking energy from the grid when it should not. There has been cases in which it has been found them injecting energy into the grid as well!, when in theory this kind of inverters are not designed for that. So withoiut the AC in sensor, they cannot monitor if the system is working "as expected".

-they have an horrendous monitoring software, in which is not possible even to overlap multiple plots, so we cannot correlate what is happening and when from a single view.

-The wifi app is a joke. 

-No web interface, to analyze the plots in detail.


Your meter could fit very well in these cases of unhappy clients, and in general for inverters that doesn't have a good enough monitoring enviroment. Your meter has very interesting features that may help with:

-Analysis of the energy taken from the grid, and in the case of using the 3 phase meter, the other two sensors could be used to monitor the produced AC out power, plus one extra load that we could want to have monitored.

-Hability to control sonoff devices based in the desired logic control. It is really helpful, if we configure it properly, we could spread the non essential loads along the day, so that we could reduce the contracted power, or take advantage of the hours with more sun to warm water for example, if there are no other loads on.

-Every inverter usually have its own monitoring system. But it is usual to see installations with a mix of different brand inverters (for example one hybrid plus another ongrid connected to the AC out of the hybrid with a few extra modules). It happens often when the client want to update an old PV installation. These installations are difficult to integrate in one app. So your system could be helpful as the main monitoring device for the total consumed AC power taken from the grid, and total produced AC power of the group of inverters.


With respect the DC sensors, would be marvelous to be able to monitor the PV production and the Battery usage. But for that we would need not only DC sensors, we would need also to measure the PV array voltage, and the Battery Voltage...(to calc watts, and watts-hour). It would be needed a more complex device, with more inputs, and a few shunts. If this device is going to be developed, then I would suggest also to leave one extra rs232 port available, to be able to control the inverters working mode based in the measured data.

I'm automation engineer, and I have access to multiple offgrid installations that would be more than happy to test your devices if needed.

Best regards.











Alternatively, I think that 2xAC sensors + a com port would be enough: we could query all the DC part asking to the inverter though rs232. Most of the inverters are able to be queried, to get PV voltage and current, and battery voltage and current.


im currently running the wem3080t in a single phase PV system. my CT sensors were as follow:

CT1-"grid" it measures import and export enegry from grid.

CT2-"load" - measures my load of the house

CT3- "inverter" - measures power generated by my PV inverter.

it will be nice if PV generation and Batt charge and discharge will be integrated to our iammeter product.


my setup:

5.5kwp mono PV

5.5kw infinisolar hybrid inverter (netmetered)


glad to know more how we can integrate more products to our iammeter.. thanks LaoLiu for the support!

Thanks abujared and danitegue

we will consider your suggestion above.

it will be nice if PV generation and Batt charge and discharge will be integrated to our iammeter product.


im currently running the wem3080t in a single phase PV system. my CT sensors were as follow:CT1-"grid" it measures import and export enegry from grid.CT2-"load" - measures my load of the houseCT3- "inverter" - measures power generated by my PV inverter.it will be nice if PV generation and Batt charge and discharge will be integrated to our iammeter product.my setup:5.5kwp mono PV5.5kw infinisolar hybrid inverter (netmetered)glad to know more how we can integrate more products to our iammete

DC monitor will be great use as I think with that we can directly monitor the solar generation from solar input side and battery charge and discharge current.. however when it's not available you can at least create some interface with 2 CT one to the grid input side and one is to load side and show how much is being used from solar + battery in a day. Here u only need to detect the grid CT use that day and minus it from the output side.. 

Hi dahampathiThanks for your information.Maybe we will consider introduce some DC monitor solution in IAMMETER in near future.Then ,if you have interested in it, we will invite you as the earlier user.(we will send you the DC meter to you for free and looking forward to your further feedback)BR

Yes, we decide to add an option in the meter type of "inverter" (off-grid or grid-tied)


Then we will use different logic to calculate the solar yield data.
If it is a gird-tied inverter,
the solar yield is the meter`s reading directly(with meter type of "inverter").
If it is an off-grid inverter,
the solar yield is the meter`s reading(meter type "inverter") minus the reading of the meter installed on the grid side.

DC monitor will be great use as I think with that we can directly monitor the solar generation from solar input side and battery charge and discharge current.. however when it's not available you can at least create some interface with 2 CT one to the grid input side and one is to load side and show how much is being used from solar + battery in a day. Here u only need to detect the grid CT use that day and minus it from the output side.. 
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