My solar system feeds back to the grid but I am concerned that my meter ( it’s a traditional type) is recording the units as usage as well. My electricity bill is still the same as before the solar was installed. I discovered this issue with a prepaid meter in my small cottage . I would appreciate any advice with this matter. Thanks 

What inverter have you got? Is it installed with a CT coil to control the export? What export-control settings are you using?

In principle you should not be exporting power unless you have an approved installation with a bi-directional meter.

3 hours ago, evegunns said:

My solar system feeds back to the grid but I am concerned that my meter ( it’s a traditional type) is recording the units as usage as well. My electricity bill is still the same as before the solar was installed. I discovered this issue with a prepaid meter in my small cottage . I would appreciate any advice with this matter. Thanks 

You can't just feed back and expect things to work. Most meters won't cope with this very well. The ways in which they don't cope vary according to the make and model of the meter. You'll need to sign up for a reseller's tariff, and this will require either a new meter or a change to your existing meter.

Elsewhere on the forum you mentioned that you had had a pre-paid meter installed. Most pre-paid meters won't distinguish between power coming from the grid and power going TO the grid.

Thanks for helping with advice. My current electrical system is 3 phase so we have 2 8kva Dye inverters with relevant batteries and panels etc. Our escom meter is a Polyphase Energy Meter Type 5219B. Our solar installer set our system up to export excess power to the grid and told us the meter would slow down or reverse? Well, I don’t think this is happening as our electricity bill is averaging slightly more than before we installed the solar. We are only using the escom as a backup during bad weather which isn’t very often. I live in Dullstroom.

 I would appreciate any advice on this matter. Thank you.

5 hours ago, evegunns said:

Thanks for helping with advice. My current electrical system is 3 phase so we have 2 8kva Dye inverters with relevant batteries and panels etc. Our escom meter is a Polyphase Energy Meter Type 5219B. Our solar installer set our system up to export excess power to the grid and told us the meter would slow down or reverse? Well, I don’t think this is happening as our electricity bill is averaging slightly more than before we installed the solar. We are only using the escom as a backup during bad weather which isn’t very often. I live in Dullstroom.

 I would appreciate any advice on this matter. Thank you.

Is this power meter a prepaid unit? 

This is not a prepaid meter 

6 minutes ago, evegunns said:

This is not a prepaid meter 

After installation were you shown that your meter does reverse with solar working and your load switched off? 

Some meters have a ratchet in place to prevent illegal sending power back to the grid. 

As mentioned by others one has to get a bi-directional meter from the grid supplier at a high cost for your account. That is why very few people go the route to export as it does not make sense in most cases to only get a few cents for exporting power. 

Don't export unless you have a contract to do so. If you don't, you will be billed for export. The only meters that will turn backwards by default is old mechanical meters without a ratchet, but even if you have one, exporting is still against the law.

On 2024/05/02 at 7:34 AM, evegunns said:

Thanks for helping with advice. My current electrical system is 3 phase so we have 2 8kva Dye inverters with relevant batteries and panels etc. Our escom meter is a Polyphase Energy Meter Type 5219B. Our solar installer set our system up to export excess power to the grid and told us the meter would slow down or reverse? Well, I don’t think this is happening as our electricity bill is averaging slightly more than before we installed the solar. We are only using the escom as a backup during bad weather which isn’t very often. I live in Dullstroom.

 I would appreciate any advice on this matter. Thank you.

On the inverter screen, find the setting for "System Work Mode" then tick the option for "Zero Export to CT."

Then also make sure that you do NOT have a tick against the box for "Solar Sell."

Monitor if it makes a difference in your usage as measured by the meter. If the CT coil was installed, then it should stop exporting to the grid, and just send power to your premises from solar.

Can't speak for the fact that you have only 2 inverters on a 3-phase supply. Could it be that the 3rd phase without an inverter is carrying more of your loads?

Lastly, your solar installer seems to have advised you to do something you probably shouldn't. Maybe have a friendly chat with him about that.

When PV production is > household use, just watch your electric meter, does it wind backwards, one can see the direction of travel if one looks closely and then check if your actual meter numbers also decrease...

Thank you Greenfields and other members for your advice. Our solar system was installed on a business premises during desperate times last year, by a local electrician that claimed to know all about solar installation! We are now learning about this system ourselves as we were certainly conned by his apparent knowledge. The guy also doesn’t take our calls now ! Is there a way to check if a CT coil was installed? We have unticked the boxes as you advised. We have 3 phase which is apparently split between the two inverters.

1 hour ago, evegunns said:

Thank you Greenfields and other members for your advice. Our solar system was installed on a business premises during desperate times last year, by a local electrician that claimed to know all about solar installation! We are now learning about this system ourselves as we were certainly conned by his apparent knowledge. The guy also doesn’t take our calls now ! Is there a way to check if a CT coil was installed? We have unticked the boxes as you advised. We have 3 phase which is apparently split between the two inverters.

On your System Flow chart the CT should be shown. Also during operation the Status Page will also show a value for the current going through the CT. 

Only 1 CT is used even for 3 ph systems IIRC. 

Being new to solar and learning, what and how does the CT work. 

Also how is the home disconnected from the grid and not pushing power back should someone be working on the grid? 

Thank you. 

9 hours ago, Herbie. said:

Being new to solar and learning, what and how does the CT work. 

Also how is the home disconnected from the grid and not pushing power back should someone be working on the grid? 

Thank you. 

The CT implies it is a current transformer as opposed to normal common voltage transformers. If the ratio is 100/1 it means for 100A through the core in the middle 1A will flow on the secondary which is small enough to be signaled to the inverter and the same ratio applied to give a reading on the display. 

The inverter would sense that the grid is down and by law it must then stop supplying power to the grid side. Thus the inverter has the switch to go to an off position during a grid failure to prevent people being shocked on the supply side. 

The CT's function is to measure power fed back to the grid if the inverter is set to do it and you do it legally. And also to measure what power is used from the grid. 

Thanks, I wasn't 100% sure because someone send me a Pic of his app showing he is pushing power back into the grid after he added more solar panels. I asked if they changed breakers or anything and fitted a current transformer and he said no they only changed the settings on the inverter. 

3 hours ago, Herbie. said:

Thanks, I wasn't 100% sure because someone send me a Pic of his app showing he is pushing power back into the grid after he added more solar panels. I asked if they changed breakers or anything and fitted a current transformer and he said no they only changed the settings on the inverter. 

It mostly is just settings. My system is set to not export, but I can change it. I just don't want to. Firstly because I don't think my meter is going to run backwards, so I'll end up paying for that power (or the meter will trip). Secondly because the reseller tariff available to me is unattractive, I will lose on the deal. 

I hope your friend is keeping an eye on his meter & his bill. 

Will ask him to keep an eye on his bill. 

Thank you

20 hours ago, Herbie. said:

Also how is the home disconnected from the grid and not pushing power back should someone be working on the grid? 

Any inverter connected to the grid shall be equipped with a SDU( safety disconnect unit) that adheres to the specific spesifications contained in NRS 097. Below extract from NRS 097.

12 hours ago, Herbie. said:

Thanks, I wasn't 100% sure because someone send me a Pic of his app showing he is pushing power back into the grid after he added more solar panels. I asked if they changed breakers or anything and fitted a current transformer and he said no they only changed the settings on the inverter. 

Not all real hybrid inverters can accept a CT. Those that can accept a CT and not fitted will thus export excess power to grid. In such a case the setting might have no idea of the level of export. Some you can adjust the export as a % of PV generated or else just disable the hybrid function if no export to happen in the settings. 

Those inverters that do use a CT will use it's reading to know when to throttle if one does not want to export and perhaps read power exported as power used or even worse to trip the prepaid as if it is in tamper mode.