Increased power consumption following Solar PV installation

MWT

https://forums.moneysavingexpert.com/discussion/comment/82051666#Comment_82051666

or the power used to power the smart meter.

No, that comes from the grid side, but I agree that the very low figures are either a calculation error or just slight lap in the battery inverter covering the house load, and too low to be an issue anyway.

Heedtheadvice

Don't wish to digress too much on the comment about those 3W. However for clarity my understanding of itm2's statement is that the inverter app is reporting 3W from the grid. Yes that meter self consumption is, by design of the meter, not measured by the meter and not billed.

The inverter grid measurement comes from the clamp Current Transformer and from the picture provided it seems to me to be on the phase line upstream of the smart meter ( grid side not load side) and as such would measure that meter self power consumption. It is a poor position and if it is actually incorrectly positioned it should be moved to the house load side of the smart meter.

As we would all agree, a fairly minor affect but worth moving as it is exceedingly simple to do DIY. Just one less error to take account of and avoid a bit of confusion.

squirrelpie

As we would all agree, a fairly minor affect but worth moving as it is
exceedingly simple to do DIY. Just one less error to take account of and
avoid a bit of confusion.

Moving a CT generally involves opening the CT to take it from where it is and put it wherever it should now be. That can be dangerous if there is still current in the wire it is clamped on, which there generally will be if it is before the meter. So no, it's not a DIY job unless you know exactly what you're doing.

MWT

No matter how much you try there will always be a small amount of 'leakage' in both directions as the inverters response to the load changing requiring a finite amount of time.

itm2

If the problem is indeed with the positioning or accuracy of the CT clamp reading, how much of an issue is this for me, from the perspective of the efficient functioning of the inverter? Will these skewed readings affect the inverter's ability to make the correct decisions re. when to charge/discharge the battery, for example?

The support guy from Fox-ESS just got back to me, asking me to send a photo of the meter as well as a screenshot from the Fox app, taken at the same time. I'm not sure how much use that will be to them, as the meter doesn't show actual load, AFAIK (only a cumulative consumption figure since the meter was installed).

MWT

https://forums.moneysavingexpert.com/discussion/comment/82052937#Comment_82052937

Insignificant.

As long as the CT clamp is performing within normal limits of accuracy, it is not going to make a noticeable difference if it is measuring before or after the meter.

Heedtheadvice

Quite. As mentioned before 3W is insignificant and not the cause of your original concern.

https://forums.moneysavingexpert.com/discussion/comment/82052872#Comment_82052872

@Squirrelpie. That is an interesting perspective on CT safety. I am all for safety and would not wish to suggest something that is unsafe. Can you give specific information as to why you have the opinion that moving one would be dangerous?

itm2

The guy from Fox-ESS support has just got back to me to say that as far as they can see the system is "correct and operational", even with the before and after data that I have provided them.

I hope this doesn't get difficult with the installers….

squirrelpie

Can you give specific information as to why you have the opinion that moving one would be dangerous?

When the primary is live, opening a CT can cause voltage spikes of several thousand volts in the worst case. That can destroy the sensor's input circuit at best.

squirrelpie

What are the sources of the before and after consumption data you posted at 6:18 pm?