Neurio for new breakers

[Shygar]

I had my powerwall and solar installed in Sept, but now I want to install a Tesla wall connector in my remaining breaker at my main panel (1 breaker for entire house, 1 breaker for AC unit, 1 breaker not used but will use for wall connector).

I read somewhere that it uses Neurio to monitor the power usage and send it to the app. I haven't opened up my panel but theoretically will I need another Neurio unit to monitor that last breaker? Or should it be installed in such a way that everything is monitored?

 

[Shygar]

I may have answered my own question. After watching this video, it looks like the sensors go over the main wires coming into the house, not on individual breakers.

 

[GenSao]

Just to be sure, confirm where your installer placed the sensors. Ideally it is at the main wires coming into the house, but they may be placed elsewhere. Such as in the Tesla Gateway or somewhere in between.

 

[Parzival]

You will not need to do anything special with that Neurio when you add circuits.

 

[Shygar]

So I opened my main panel today and I see that they put the sensors over the breaker to the main house, not the wires coming into the entire enclosure from the meter. But one interesting thing is I do see my energy spike when the AC kicks on but I'm not sure why now since the sensors appear to not be covering the AC breaker.

 

[Ampster]

So which load do you want to measure? I assume from what you are saying, the main house is on a subpanel? You can put them anywhere you like depending on the load you want to measure.

 

[ctslc]

So I opened my main panel today and I see that they put the sensors over the breaker to the main house, not the wires coming into the entire enclosure from the meter. But one interesting thing is I do see my energy spike when the AC kicks on but I'm not sure why now since the sensors appear to not be covering the AC breaker.
View attachment 270056

 

[ctslc]

So I opened my main panel today and I see that they put the sensors over the breaker to the main house, not the wires coming into the entire enclosure from the meter. But one interesting thing is I do see my energy spike when the AC kicks on but I'm not sure why now since the sensors appear to not be covering the AC breaker.
View attachment 270056

The Neurio that you show in the picture is probably the one used to monitor the production of the PV system - I see what looks like shiny, new hardware on the conduit fitting of the wires on which the Neurio was placed and I'd guess that the
circuit breaker is labeled as being for the PV.

There is a Neurio in the Gateway itself that monitors the power flow to/from the power grid, so you would not see it unless you happened to open that panel.

Only two Neurio monitoring points are required - the one on the grid and the on on the PV system - as the Powerwalls themselves can monitor their power inflow/outflow internally. Only these three pieces of info are all that are needed for management of the power flow.

CT

 

[Shygar]

So which load do you want to measure? I assume from what you are saying, the main house is on a subpanel? You can put them anywhere you like depending on the load you want to measure.

I want to also measure the bottom left breaker as I'm about to have my Tesla wall connector installed on that one. Yes everything in the house is on a subpanel except the AC (bottom right breaker) and soon to be wall connector (bottom left).

 

[Shygar]

The Neurio that you show in the picture is probably the one used to monitor the production of the PV system - I see what looks like shiny, new hardware on the conduit fitting of the wires on which the Neurio was placed and I'd guess that the
circuit breaker is labeled as being for the PV.

There is a Neurio in the Gateway itself that monitors the power flow to/from the power grid, so you would not see it unless you happened to open that panel.

Only two Neurio monitoring points are required - the one on the grid and the on on the PV system - as the Powerwalls themselves can monitor their power inflow/outflow internally. Only these three pieces of info are all that are needed for management of the power flow.

CT

Actually I opened up my backup gateway and saw the solar piece of it. So the previous picture is definitely the load of the house. I just don't get how it is able to measure the AC, or maybe it is really not measuring it.

 

[mongo]

I want to also measure the bottom left breaker as I'm about to have my Tesla wall connector installed on that one. Yes everything in the house is on a subpanel except the AC (bottom right breaker) and soon to be wall connector (bottom left).

Are you sure on those breaker positions?
It looks to me like the bottom right breaker is the main feed to the gateway (formerly fed the house, but now spliced to new wires to the gateway) and then the house.
Lower left unused.
Upper left is separately measured, is that the AC?

Additional question: do you see the running load of the AC or only the initial turn on spike?

 

[Shygar]

Are you sure on those breaker positions?
It looks to me like the bottom right breaker is the main feed to the gateway (formerly fed the house, but now spliced to new wires to the gateway) and then the house.
Lower left unused.
Upper left is separately measured, is that the AC?

Additional question: do you see the running load of the AC or only the initial turn on spike?

You know, that's a good question. That's what the Tesla guys explained to me but now that you mention it it does seem that the breaker at the top may not be used how I thought.

Regarding the AC, I know I saw the initial spike but I'm not 100% sure that you could see it for the duration of running. I'm pretty sure you could but not 100%. I know the AC is not backed up by my one powerwall but everything else is.

 

[mongo]

You know, that's a good question. That's what the Tesla guys explained to me but now that you mention it it does seem that the breaker at the top may not be used how I thought.

Regarding the AC, I know I saw the initial spike but I'm not 100% sure that you could see it for the duration of running. I'm pretty sure you could but not 100%. I know the AC is not backed up by my one powerwall but everything else is.

Well, based on the two pictures and wire runs, it definitely looks to me like the upper left is sensed by the gateway via the remote clamps and the bottom right is the main feed sensed by the gateway itself.

There does not seem to be additional inputs for another set of current probes.
One option would be to run both loads cables through one set of clamps (observing phasing and load/source direction), that would give you total load from both circuits.
A less likely option (requires software support) would be to use one clamp for each circuit (since they are 240V loads).

 

[Shygar]

Well, based on the two pictures and wire runs, it definitely looks to me like the upper left is sensed by the gateway via the remote clamps and the bottom right is the main feed sensed by the gateway itself.

There does not seem to be additional inputs for another set of current probes.
One option would be to run both loads cables through one set of clamps (observing phasing and load/source direction), that would give you total load from both circuits.
A less likely option (requires software support) would be to use one clamp for each circuit (since they are 240V loads).

My install is this Thursday for the wall connector so I'm hoping they know enough about this to explain what I can do and if it will monitor everything. I don't have my model 3 quite yet so I can't actually test it unfortunately.

 

[ctslc]

My install is this Thursday for the wall connector so I'm hoping they know enough about this to explain what I can do and if it will monitor everything. I don't have my model 3 quite yet so I can't actually test it unfortunately.

The Neurio measures both AC voltage and current. If you look closely you'll see that the Neurio monitoring your solar is powered from a breaker somewhere: On my PV system, they installed an entirely new breaker in the sub-panel for that - it not only allows voltage measurement, but power for the unit as well.

In the gateway the Neurio is clearly powered elsewhere - but I didn't really check to see where its mains was connected. Since this Neurio needs only monitor grid power and current (on the "grid" side of the disconnect relay) it is entirely possible that it goes offline if the grid power fails - but this would be unimportant when operating in island/stand-alone mode as the load of the house could be calculated in that instance by subtracting the power produced from the PV system from the load/charging of the Powerwalls as determined by the Powerwalls' built-in voltage/current monitoring.

It's worth noting that the Powerwalls themselves power the BUG (Back-up gateway - the computer part in the gateway), apparently in a "diode-OR" manner if you have more than one Powerwall (e.g. any single power wall will supply DC power to it). (Note: This also means that even if you completely "power down" the Powerwalls by opening breakers/switches and turning them "off", the BUG still remains powered at all times as long as there is at least a small amount of power in a battery.) It is possible that the Neurio is powered from the same DC source as the BUG in addition to/instead of the AC mains (on the "grid" side of the disconnect relay) just in case they (Tesla) want to the grid-monitoring Neuro to remain powered even during a grid failure.

Because the Neurios seem to be connected either wirelessly or via a multi-drop RS-485 serial interface, it probably wouldn't matter if the "grid Neurio" was offline during a grid failure - but keeping it powered up would allow the system to differentiate between a grid failure and loss of communications to that "grid Neurio".

* * *

I suppose that the ultimate answer to you original question is: No, you do not need to change anything related to your Neurios at all to add additional house load(s).

In my system, my house wiring is now connected to a sub-panel of the original breaker panel to accommodate the fact that it was impossible to wire the isolation relay into the original combination breaker panel+meter. Because of circuit relocation, here are now many open slots in the original panel and I could add circuits to this panel - but they would be "unprotected", that is, not backed up by the Powerwall system. Because the original panel is "outside" the domain of the Powerwall (e.g. not backed-up) there is absolutely no need for the Powerwalls to even know about those loads, so no need to change the Neurio in that case, either.

Now, if you add more solar, you would simply route the wires from the new PV system/breaker inside the same two CTs (current transducers), paying careful attention to phasing so that the two currents would add to each other rather than subtract - and that's how my two inverter systems are monitored. One would need to add another Neurio only if the wiring of the "new" PV system were not in the same panel as the original and could not be routed through the existing CTs. By using a single Neurio the Powerwall system can only detect the total power from the PV system and not from each inverter, but it only needs to know the total. (For monitoring each inverter? I have an app for that!)

CT

 

[ctslc]

You know, that's a good question. That's what the Tesla guys explained to me but now that you mention it it does seem that the breaker at the top may not be used how I thought.

Regarding the AC, I know I saw the initial spike but I'm not 100% sure that you could see it for the duration of running. I'm pretty sure you could but not 100%. I know the AC is not backed up by my one powerwall but everything else is.

I was going to comment on the spike: Remember that the sample rate of the current monitoring is fairly slow. It is because of this that the system - at least when connected to the grid - cannot respond instantaneously to changes in power, so there are inevitably brief "spikes" when the load changes - and it is possible that there could be spikes caused by the mains voltage sagging slightly, such as when an A/C connected to the "non-protected" (grid) side of the Powerwall starts up and power from the Powerwall/PV system can't track instantly as described below.

When the system is grid-connected and in "self powered" mode it has to do a delicate balance between charging and supplying power to/from the house while keeping the overall grid power "zeroed out". Because it cannot respond instantly, you end up with that 0.1kW/day or so grid usage even when "self powered" (but grid-connected) because of the monitoring lag and also do to the normal fluctuations in the power grid. This may also explain why, when there is a grid failure, it can take between 0.2-0.75 seconds for the Powerwall to completely restore the power to the house, hence the continued need to have at least a small UPS on some critical loads - such as computers - that may not be able to "ride through" such a transition.

In "Backup-only" mode there is still that lag when it is charging, trying to precisely match the PV output with the battery charging rate while keeping the grid usage and house power consumption equal.

The Powerwalls themselves appear to be able to respond instantly with respect to their own, internal monitoring, so that is why - when one is off-grid - it can handle sudden changes in power - in both charging and supplying power. When off-grid it doesn't need to worry about trying to zero-out the power to/from the grid or trying to match the power from the PV - both of which rely on rather slow, external monitoring - but, at least in the short term it can monitor and adjust its own in/out power flow instantaneously without any external consequences.

CT

 

[Shygar]

Thanks for the detailed information! I did also wonder why I was always seeing that 0.1kW from the grid and you could see the little bumps throughout the day from the grid.

 

[Shygar]

Hi everyone, so I had the Tesla Wall Connector installed on Jan 4th in that bottom left breaker with a new 60 amp breaker. This past weekend I rented a Model X for a roadtrip and finally got to test my wall connector. With the setup from how Tesla configured my Neurio CT clips (being on the AC only), it did not detect any drain from the wall connector. So I moved the CT clips to be on the main power coming into my panel after the meter (see post #5's picture above, left side shows the two large cables coming into these 3 breakers). After moving it there, it did correctly measure a load while charging the X.

The problem I have now is, after moving it, it seems my numbers are way off. It's showing things like the solar producing 10.4kW (even though I have a max of 6.6kW) and it also shows the solar feeding directly to the grid and nothing to the battery or the house. If I move the CT clips back it seems to go back to normal, but then it's not measuring the load from the wall connector. Since having this discussion I've installed another non-Tesla Neurio in another house so I'm much more familiar with the admin page and such. Do you think my issue is that a configuration change needs to happen to account for moving the CT clips to the main lines rather than on one of these other ones? I've sent an email to [email protected] but nothing yet.

Another thing that has occurred that I was not expecting is that when charging the car overnight, it did draw power from my battery. I didn't think this was possible because the only breaker that is backed up is my house subpanel and not the breaker for the AC or the wall connector. I just didn't think that would happen, but I guess it will feed energy to my entire house even though my whole house isn't theoretically backed up (or so I thought).

 

[wwhitney]

If you could draw and post a graph showing your service, feeders, panels, and major loads, and the location of the all the CTs, that would interesting to see. Hopefully we can figure out why you are seeing the behavior you described with respect to moving the CTs (presumably some usage is getting double counted). We may also be able to determine if there is a place to put the CTs that would get the reporting and behavior you desire; however it is possible that it can only be done with a reconfiguration of how the Powerwalls do the energy accounting using the data from the CTs.

Cheers, Wayne

 

[Shygar]

If you could draw and post a graph showing your service, feeders, panels, and major loads, and the location of the all the CTs, that would interesting to see. Hopefully we can figure out why you are seeing the behavior you described with respect to moving the CTs (presumably some usage is getting double counted). We may also be able to determine if there is a place to put the CTs that would get the reporting and behavior you desire; however it is possible that it can only be done with a reconfiguration of how the Powerwalls do the energy accounting using the data from the CTs.

Cheers, Wayne

Thanks Wayne, yea let me just take a picture of both panels uncovered and highlight where everything is so it's more clear.