No changes in KWh per day

[Sidewinder]

@Nadeem Ahmed,

I run a similar setup to yours. Truth be told, I've never even loaded or used Watchpower, as I don't have a specific setting I need to implement that I cannot do from the LCD screen. So I agree, "Single" is probably the default. Just leave at that. Mine would be parallel, as I run 2 x V's. The rest of the setting would be if you ran a full 3 ph or even 2ph setup.

BTW, I would be worried about having Battery Cutoff Value @ 42V. Batteries won't last the manufactures spec for cycles. I would change that to 47V.

[Youda]

Hi Plonkster,

I see in that screenshot that the guy is running in the offgrid mode. There's no feed-in to the grid, therefore no zeroing of phases, I would say.

AFAIK, power mixing can still occur in this mode. Same with the automatic bypass on the overload - it will work.

To me it looks like the guy is not using the batteries, running from the grid overnight and maybe even switching back to the grid several times a day.

Is that possible?

[___]

6 minutes ago, Youda said:

I see in that screenshot that the guy is running in the offgrid mode. There's no feed-in to the grid, therefore no zeroing of phases, I would say.

I don't know this inverter at all, but I know there is a way where you run disconnected from the grid (but frequency-locked) so that when you require more power than the inverter can provide it simply closes the relay and take the difference from the grid, and disconnect again soon after.

If it runs in this way, then it's going to zero just the phase that it is on, assuming a single-phase unit, or it is going to zero phases individually if it is a 3-phase setup. One would have to investigate this closer, but it may well be that if you have a single-phase inverter zeroing one phase, that the other two phases might still consume power that you get billed for.

I'm doing a lot of handwaving. I don't have the answer, just saying about places to look :-)

[Nadeem Ahmed]

4 hours ago, Youda said:

I see in that screenshot that the guy is running in the offgrid mode. There's no feed-in to the grid, therefore no zeroing of phases, I would say.

I have heard both @plonkster and you talking about zeroing of phases.  I have never heard about it. What do you mean by that?

[___]

9 minutes ago, Nadeem Ahmed said:

zeroing of phases

That's when you run grid connected with a grid limiting device. You typically fit a metering device where the feed enters the premises (or this might be built into the inverter), and then you continually adjust your power feed-in so that this metering device hovers around zero (neither drawing power from nor pushing it into the grid). Whenever there is a change in load, you will feed into- or draw from the grid for a short period of time until the inverter again adjusts.

Your system however runs in off-grid mode, which if I understand it correctly, means the grid is disconnected. This will by definition "zero" that phase, since it is disconnected.

So "zeroing the phases" is merely the process of adjusting your feed-in (where you're connected to the grid) so that all three phases are at zero.

The alternative is to run them so that the add up to zero, so some phases might not be at zero, but adding the three might get you to zero.

I have no idea what your equipment is capable of.

[Nadeem Ahmed]

5 minutes ago, plonkster said:

That's when you run grid connected with a grid limiting device. You typically fit a metering device where the feed enters the premises (or this might be built into the inverter), and then you continually adjust your power feed-in so that this metering device hovers around zero (neither drawing power from nor pushing it into the grid). Whenever there is a change in load, you will feed into- or draw from the grid for a short period of time until the inverter again adjusts.

Your system however runs in off-grid mode, which if I understand it correctly, means the grid is disconnected. This will by definition "zero" that phase, since it is disconnected.

So "zeroing the phases" is merely the process of adjusting your feed-in (where you're connected to the grid) so that all three phases are at zero.

The alternative is to run them so that the add up to zero, so some phases might not be at zero, but adding the three might get you to zero.

I have no idea what your equipment is capable of.

Thanks for explaining.  

Now I think I have a better understanding of my device.  It has another operating mode (which Axperts do not have) called SUB and I am currently using it also.  It can combine power from PV and Utility and if both are not available then it comes to Battery.  So probably this Inverter has a grid limiting device that tries to limit grid input (or perhaps put a brake on the grid supply) so that it can use PV power and whenever PV power is not enough it releases that brake to allow grid power to come it.

And the power factor issue I discussed earlier is also because of this limiting device built into this device.

One thing however is still a question, even if PV power is enough to power my load, it still use a small portion of grid too although the major chunk of power is coming from PV.  Maybe the internal circuitary  of this inverter still need to use some power from grid to operate.

[Youda]

Nadeem Ahmed,

Certain hybrid inverters are able to draw power from the grid in order to help you with starting the huge loads. So, when you're starting a motor for example, the inverter "sucks" the energy from the grid and then, after couple of seconds, when the motor is already running and the spike is over, the inverter will return the same amount of energy back to the grid. If the whole process is quick enough, you won't be billed for that energy. For example, in Europe, you have 15 seconds normally.

In the 3-phase system, there's another feature where you can continuously draw energy from 1st phase of the grid and the inverter will send the same amount of energy to 2nd + 3rd phase. In that case, the total sum will be zero, so you won't be billed. This will allow you to power a single-phase appliance that draws more power that your 3phase inverter is able to supply on a single phase.

The reality is, that your grid authority (and the meter) must support the above in order to work correctly. Otherwise, you may end-up in a situation where you will be billed twice - once for the comsumption from the grid and then for supplying to the grid. Sounds silly, but that's the life. So if you don't have a special contract, be careful when using this features.

Looking at your screenshot, it seems that you have 1-phase Inverter. So, forget anything about 3-phase.

--

SUB mode has a continuous draw somewhere around 50-100Watts. The real reason for this is to ensure that no energy will be pushed back to the grid when you turn-off an appliance and energy spike will occur. On some infini models, you can even calibrate this value. From my experience, if you want to use SUB or hybrid mode with any kind of inverter, it has to be calibrated precisely and your grid authority must support it. Otherwise, your meter will trip, you'll be billed twice or you'll get a fine from the authorities for unlawfull suply of energy to the grid.

--

I would advise to change the mode to Offgrid + SBU. This works the best, and the occasional spikes are sent to the battery. With SBU mode, you can even disconnect the inverter from the grid and then monitor the meter each day, in order to identify whether the power is being consumed or not. If the SBU mode will work correctly, then you can return back to SUB and start investigating deeper.

 

 

[Nadeem Ahmed]

4 minutes ago, Youda said:

I would advise to change the mode to Offgrid + SBU. This works the best, and the occasional spikes are sent to the battery. With SBU mode, you can even disconnect the inverter from the grid and then monitor the meter each day, in order to identify whether the power is being consumed or not. If the SBU mode will work correctly, then you can return back to SUB and start investigating deeper.

 

 

I am already off-grid.  I will try SBU for few days to see if that adds to my savings.  Someone else suggested to raise up the battery cut-off voltage to 47 instead of 42.  I will do that as well because I think it will work well in SBU mode and will not consume much on battery charge/discharge cycles.

[Youda]

Raising the battery cut-off voltage is a good move too, as it protects the battery from undercharging. AFAIK 42V is the default value for Infinisolar and translates to 10.5V per 12V battery piece.

1) Once you raise to 47V, just check whether the inverter is still able to supply your microwave or kettle. There might be a voltage drop while turning these appliances on, in which case the inverter will switch to bypass (draw from grid). If that will happen, just lower the battery cut-off voltage a bit - to 44V, for example.

2) What you have configured on the "My Power Management" screen? Do you have nightly AC charging enabled there?

If you do, your batteries will be topped up from the grid overnight, which will create additional consumption, thus increase your bill. Economically, it makes sense to charge the batteries from the PV only.

 

 

 

Edited September 17, 2018 by Youda

[Nadeem Ahmed]

19 hours ago, Youda said:

2) What you have configured on the "My Power Management" screen? Do you have nightly AC charging enabled there?

I am using SolarPower application that comes with Inverter.  When you run the application without have a USB cable connected to your inverter, "My Power Management" menu option shows up but when I connect the USB cable and this application detects it, the options goes away.

But to your question, if you look at the screen shot attached above, yes I am using nightly charging option.

Here is what my original thought was: -

1. I wanted to use my solar system to give me savings on electricity.  I do not have any plan right now to selling anything back to the power company.  So I am using off-grid mode.  In future I may plan to be on-grid.

2. I choose Infini V because that had SUB mode that allows mixing of Solar and Utility (obviously that can save me on electricity bills).  For SBU mode, I could have bought an Axpert VMII which was cheaper.  Infinisolar Plus was way too expensive.

3. Reason for not using SBU mode so far is to avoid unnecessary using battery cycles which will shorten battery life and whatever you are saving on electricity will eventually gets drained from your pocket while replacing batteries.

But my analysis so far is that I am unable to save what I was expecting reasonably when I use SUB mode (still haven't got the answer).  I will try switching to SBU mode with controlled battery parameters to get some savings without much compromise on battery life.

Edited September 18, 2018 by Nadeem Ahmed
Missed one point

[DDD]

On 2018/09/10 at 4:02 PM, Czauto said:

Stupid question. The infinisolar can be grid tied. Make sure you are not pushing electricity into the grid. If you do not have a Bi-directional meter installed your meter will measure units both ways. I had the problem with my first grid-tied setup. I was providing Eskom with electricity and paying them for it at the same time Make sure you have Zero feedback and check your usage again......

With zero feedback your panels will only generate electricity to cover your load, inverter idle consumption, etc. With feedback it will generate maximum possible and feed it back into the grid and your meter (only if bi-directional) will run backwards while doing so. Only when usage exceeds generation will it start using units again.....

Anyone who can explain it better? it's all in my head but cannot seem to get it out properly.

Put the switch on that activates the load limter

[Nadeem Ahmed]

17 minutes ago, Erastus said:

Put the switch on that activates the load limter

You mean that even if I am operating my Infini V in off-grid mode, it is still feeding back to grid? I understand what you are saying but I am ruling it out because I am off-grid.  Please clarify.