Does the Grid-Tie system power the entire house or only the individual circuit?

[JohnnyDangerDude]

Does the Grid-Tie system power the entire house or only the individual circuit?

I'm talking about the type of grid-tie in which you plug in a standard computer cable type plug into a standard electrical socket and its suppose to push the electric back into the house from that plug.

Does that plug basically back feed electric for the whole house or only things on that same circuit?

Sort of a side note, years ago we tried a power line networking device which was suppose to link your entire house using the power lines instead of having to run CAT6 cables for older houses.

The networking equipment was unable to link all the rooms via the electrical plugs maybe because they are expecting a different type of configuration. So I am wondering fi the grid-tie might have this same issue.

Thanks.

 

[DIYrich]

Circuit is tied to the grid. If you push power into the circuit, you are by physics, pushing to the grid.

The powerline ethernet is limited by signal strength, and having to travel to the main panel to come back out another circuit.

 

[JohnnyDangerDude]

Circuit is tied to the grid. If you push power into the circuit, you are by physics, pushing to the grid.

The powerline ethernet is limited by signal strength, and having to travel to the main panel to come back out another circuit.

When I say the grid, I mean the utility company's lines outside of my house/meter.

I am wondering if the grid-tie inverter will naturally try to help power the entire house or if only effects the local circuit its connected to.

Like if you overload your electrical socket by plugging in a toaster and an air frier, it may trip the circuit breaker for those outlets in the kitchen but not the entire house.

If you had a grid tie inverter plugged into that circuit, would it try to help other devices not plugged directly into that circuit such as the freezer, air conditioner, etc... ?

 

[rpdom]

I believe in the US you tend to have a split phase supply with some outlets running off one 120V Live circuit, some off the other 120V Live and some using 240V from both Lives.

The inverter will backfeed to your panel and from there into all house circuits on the same 120V Live feed. It won't feed circuits on the other 120V Live.

Any excess will go out to the utility company's grid, which they can get rather peeved about if you haven't got an agreement with them.

 

[Q-Dog]

If you backfeed 1000 watts into a branch circuit, but the loads on that circuit only need 500 watts, the other 500 watts will go through the breaker panel and into other circuits. If no other circuit needs power, it will backfeed onto the grid.

 

[juliawhites]

Does the Grid-Tie system power the entire house or only the individual circuit?

I'm talking about the type of grid-tie in which you plug in a standard computer cable type plug into a standard electrical socket and its suppose to push the electric back into the house from that plug.

Does that plug basically back feed electric for the whole house or only things on that same circuit?

Sort of a side note, years ago we tried a power line networking device which was suppose to link your entire house using the power lines instead of having to run CAT6 cables for older houses.

The networking equipment was unable to link all the rooms via the electrical plugs maybe because they are expecting a different type of configuration. So I am wondering fi the grid-tie might have this same issue.

A grid-tie system plugged into a standard socket typically only powers the circuit it's connected to, not the entire house. Issues with power line networking could indeed affect grid-tie systems similarly, especially if the electrical configuration is not ideal.

 

[RCinFLA]

I'm talking about the type of grid-tie in which you plug in a standard computer cable type plug into a standard electrical socket and its suppose to push the electric back into the house from that plug.

They feed into a given house breaker branch which goes back to main breaker panel where it can feed into other house branches or back feed to grid.

These units are illegal to connect to house and dangerous. If it produces more than your house consumes at any given moment, a smart utility meter may alarm utility to uncertified back feeding occurring.

If you unplug the cord male plug from house outlet, the exposed male plug prongs can stay live for 10-15 seconds before shutting down inverter.

 

[Mattb4]

Grid tie parallels with grid in order to export. It is a fiction to say you are powering only your own loads since once in parallel all loads are felt by all supplies. The 600w it picks up is reduced off the grid generators. Your house load becomes less. No it does not just power one circuit nor one side of a split phase setup. Even the so called zero export units that use CT's to monitor current flow do not prevent all export.

 

[Lawrence_SoCal]

Does the Grid-Tie system power the entire house or only the individual circuit?

Hoping I'm not over-simplifying this

A common grid-tied (inverter) system can be configured to power an entire home, or a portion (down to single circuit). it depends on your situation. Though, one's entire house tends to be grid tied by definition (ie power from power company, thru meter to main load center (breaker panel)

Grid-Tied vs off-grid in this forum tends to refer to the inverters used with solar and/batteries. In that context,
- for a home where electrical load is within spec range of the inverter, then a common configuration is

Power Company (PoCo) meter to Inverter to Main Load Center (main panel with breakers). ie the entire home (all circuits) are powered​

- for some folks, whole house electrical load is greater than single typical hybrid inverter can handle (or is more than solar/batteries can support), so a critical loads sub-set of circuits is created (typically a sub-panel). so the setup is

PoCo meter to Main Load Center (main panel with breakers) to Inverter to a sub-panel ('critical loads').​

As for data networking, Powerline networking crossing circuit breakers is its own whole issue/topic, unrelated to typical gird-tied hybrid inverter. Though a grid-tied inverter covering only a portion of a house, and trying to do powerline networking across that inverter.... yea... not something I'd even try (then again, I won't touch powerline to begin with... I ran Ethernet to most places (6ft long drill bits and patience do wonders when bringing Ethernet cable down from attic through fireblocks into rooms), and used WiFi (which I don't trust) to the rest. I did get creative on one Ethernet run from 2nd story attic down to garage into main living room (running under lip of chimney mantle for 10+ft). I only have 1 room downstairs not reached by ethernet (next to kitchen, with natural gas line in shared inside wall... will wire once I get an appropriate borescope.. probably Ethernet wire at same time as run of 240V wires if/when replacing natural gas stove and oven with electrical models ... naturally with more than 12" of separation between power and data wiring)

 

[RCinFLA]

Only a current sensor with power flow calculations can manage back fed power. This means voltage and current phase relationship is measured to determine direction of power flow.

CT sensors have accuracy tolerance so some reserve margin must be held to avoid accidental back feed. Inverters have feedback control response delay so there can be short periods of back feeding when a load within the allowed power draw domain is shut off and the inverter output must be reduced to prevent grid back feeding.

Poor power factor adds to complexity in determining power flow direction requiring cycle period averaging. This further delays the response time for inverter output management in order to avoid back feed. An induction AC motor usually has an inductive power factor less than 1. It will back feed power for some portion of the AC cycle but the average for a full AC cycle will be a consumption load.

A battery powered hybrid inverter with subpanel only restricts what loads can be backed up by a battery powered inverter when grid is lost. Subpanel has nothing to do with back feeding. It is up to CT sensor hooked to hybrid inverter AC input, either internally on AC input port or remote external CT sensor at some upstream AC input path, out to grid service entrance wires. The point the CT sensor is placed determines the zero back feed reference point. If external remote CT sensors are placed on grid service entrance wires from utility, that point becomes zero back feed reference point. Hybrid inverter can back feed power to supplement grid power for main breaker panel loads and prevent back feeding to grid. There may be short squirts of grid back feed as hybrid inverter feedback control adjust inverter back feed amount to only supply a maximum of main breaker panel subcircuit loads. Smart meters will not react to this as they already have to accept short period back feeds from AC motors.

There are battery-less PV grid-tie inverters with external remote CT sensors that can prevent grid back feeding.