utility meter sensing.

[solga]

How to sense when utility power and solar power equal. This would help me to redirect my solar power. Ga. Power meter showed a dot reversal. But I need a electrical signal!

[inetdog]

How to sense when utility power and solar power equal. This would help me to redirect my solar power. Ga. Power meter showed a dot reversal. But I need a electrical signal!

No simple way that I know of. A camera and software watching the dots will do the job in a pinch.
A separate power direction detector (directional power relay) may be the way to go, but they are expensive.

[solga]

utility meter power sensing

No simple way that I know of. A camera and software watching the dots will do the job in a pinch.
A separate power direction detector (directional power relay) may be the way to go, but they are expensive.

I wonder how utility meter detects power direction? Could I use same procedure?

[SunEagle]

I wonder how utility meter detects power direction? Could I use same procedure?

Their meters probably have a "directional" sensor/control to determine if they are supplying or receiving power.

You have to understand a lot of engineering went into designing those smart meters including the software to run all of the diagnostic parameters.

[inetdog]

I wonder how utility meter detects power direction? Could I use same procedure?

The utility meter detects power direction and also figures out your energy usage, not just the amperes used by measuring both the voltage and the current (including direction) many times per cycle. It multiplies the voltage times the current at each measurement and then adds up the samples.

If the L1 terminal is positive with respect to ground and current is flowing toward your house, energy is going toward your house. When the L1 terminal is negative with respect to ground and current is flowing away from your house you are still buying energy from POCO.
If the current is opposite in direction to the polarity of the voltage, then you are selling energy to POCO.
It gets more complicated if you have motor loads or other inductive loads on your system because the energy will be flowing is opposite directions at different points in the cycle, and you (or the meter) have to figure out which flow is greater to determine the net transfer of energy.
Getting your own digital meter with an output which gives the sign and magnitude of the power may actually be the simplest way to do what you want. Take a look at TED, for example.

[foo]

metering

You get a new meter from the POCO specific for your solar installation?
If you didn't and still have your normal residential meter, those meters still accumulate forward kwh energy even when receiving energy. Reverse polarity will still get charged as kwh usage and some meters won't display that reverse flow as they are detented. They designed them that way to prevent people from being able to insert the meter upside down in hopes of reversing the meter via usage that would make the disc spin backwards. Something that was done with old electromechanical meters.
I believe meters in some areas for solar installations will have two units displayed on the meter. One for kwh to the customer and one for kwh back to the POCO.

[solga]

i do have a new utility meter SOCO MTR TYPE FOCUS AXR LANDIS+GYR SMART METER

I contacted utility co and got a definition of my new meter codes. POCO issued email acknowledging they are not paying me for my generated electrical KWH'S going to the utility. So this is why I am trying to redirect my KWH'S. I Would like to expand my PV Solar array but with excess going to POCO gives me a negative economic enforcement. I would like to expand to start supplementing my heating but without net metering it's a much Moore difficult thing to do. One suggesting is using a timer to redirect energy to heating elementsh during day when you know you are over generating, but this is watching the clouds.
I know I will solve this problem with the kind of feed back I am getting from some smart guys! THANKS A LOT!!!

[Sunking]

Couple of comments.

1. Solar production and usage is extremely dynamic changing every second. Virtually no way you could make or manufacture a device to switch loads off and off fast enough.

2. If you have no Net Metering, then why the heck do you have solar. You have no possible way to ever get a payback and is only a liability. Not to mention no one would buy your house with that ball and chain wrapped around it because it is a liability, not an asset.

[Johann]

I wonder how utility meter detects power direction? Could I use same procedure?

The older meter with the wheel in it is working exactly on same principle as a AC motor.

Just figure (for example) you have a Ac motor. You hook up one lead to the power net/one phase, then the 2nd lead you hook up to a power-user/device lets say a light bulb. Then you hook up a neutral from the light bulb to the neutral at the net. Everything is hooked up in series.
Now lets play a little.
If you use a 20 watt light bulb, the motor will spin since power has to go through the motor. If you use a 100 watt light bulb, the motor will spin faster since you increased the amperage by using a higher wattage light bulb.
If you use the motor with a light bulb in a 120 volt circuit it will spin, if you would use the motor in a voltage that is higher or lower then the motor would spin faster or slower depending on voltage.

All the power you use in your home etc etc, will go through the motor/ meter that will turn that wheel with dot and that wheel will turn the counter.

The coils inside the meter is the stator like in a electric motor. All the power you use will go through those coils that energizes and turns that wheel with the dot.
The rotor inside the meter is the disc with the dot on it, that will turn your counter on the meter also.

The higher voltage and the higher the amps you use , the faster the meter is turning.

And if you push power the other way then you motor/meter will run the other way or backwards.


How the electronic meters/smart meters work I do not really know.
But I think they are just measure the volt and the amps and then they multiply to get the wattage.
And I think that is why they do not turn their numbers backward, they just see amperage and voltage and it does not matter if the actually current is going backwards or forwards but they are able to display those numbers in forward mode only.

[Johann]

I wonder how utility meter detects power direction? Could I use same procedure?

The older meter with the wheel in it is working exactly on same principle as a AC motor.

Just figure (for example) you have a Ac motor. You hook up one lead to the power net/one phase, then the 2nd lead you hook up to a power-user/device lets say a light bulb. Then you hook up a neutral from the light bulb to the neutral at the net. Everything is hooked up in series.
Now lets play a little.
If you use a 20 watt light bulb, the motor will spin since power has to go through the motor. If you use a 100 watt light bulb, the motor will spin faster since you increased the amperage by using a higher wattage light bulb.
If you use the motor with a light bulb in a 120 volt circuit it will spin, if you would use the motor in a voltage that is higher or lower then the motor would spin faster or slower depending on voltage.

All the power you use in your home etc etc, will go through the motor/ meter that will turn that wheel with dot and that wheel will turn the counter.

The coils inside the meter is the stator like in a electric motor. All the power you use will go through those coils that energizes and turns that wheel with the dot.
The rotor inside the meter is the disc with the dot on it, that will turn your counter on the meter also.

The higher voltage and the higher the amps you use , the faster the meter is turning.


How the electronic meters/smart meters work I do not really know.
But I think they are just measure the volt and the amps and then they multiply to get the wattage.
And I think that is why they do not turn their numbers backward, they just see amperage and voltage and it does not matter if the actually current is going backwards or forwards but they are able to display those numbers in forward mode only.

[+3 Golfer]

....
How the electronic meters/smart meters work I do not really know.
But I think they are just measure the volt and the amps and then they multiply to get the wattage.
And I think that is why they do not turn their numbers backward, they just see amperage and voltage and it does not matter if the actually current is going backwards or forwards but they are able to display those numbers in forward mode only.

I would believe that smart meters can be programmed to only "read" power supplied by the utility. But when there is generation behind the meter and with net metering, the smart meter increments and decrements depending on the direction of power flow for various period depending on the rate tariff. So, when the meter is read, the meter readings can be higher (net power supplied by utility) or lower (net power delivered to the utility)than the previous months meter readings.

[foo]

metering

The digital meters that display only one reading will not help your bill. The net metering set up by your POCO will typically use either two meters or one meter with two values displaying, once cycling into view after the other. They have to use the two readings to track usage/billing and the amount of power generated by you.
The two values are needed to subtract from your bill.
If you have one meter with only one KWH value displayed while you are using a Grid-Tied system, you are most likely losing money as that one meter is accumulating both outgoing and incoming power as billable usage.
There might be some POCO's that do this differently, and if you're sure that they actually did put a newly programmed meter that is only suppose to display one value for both usage and generation, please reply. It would be interesting to know that.

Edit: I have been told by a utility worker who seemed to know more on the matter that the new wireless meters can be purchased with the ability to be programmed to perform net metering by subtracting generation from your usage. He said that they don't do that at his company because they need the generation info recorded as well for record keeping. So they will use a meter with both values displaying.
Ok, so it is possible but it will need to be specially ordered and installed. If that hasn't happened, or you haven't seen a new meter show up since your installation, you will want to take a closer look at what you have going on with your billing.

[taylor]

I have 2000 wat system. I will never generate more power than what my house uses. But It still decreases my bill. Do I need net metering?

[Sunking]

I have 2000 wat system. I will never generate more power than what my house uses. But It still decreases my bill. Do I need net metering?

Yes, otherwise you are screwing yourself. While it maybe true you will never more power than you use in a month, you still send power out on the grid at times. Without a net metering contract with the utility, the power you send out on the grid will be billed as power used by you. In otherwords you pay the POCO for what you generate and send out to them. With a valid contract and net metering the excess is a credit on your account.

For example if you generate 8 Kwh in a day during the day light hours, but only use 6 Kwh, that gives you a 2 Kwh credit to use at night after the sun goes down. With out a Net Metering contract you get billed for that 2 Kwh you sent them.

Power use is very dynamic and changes by the second. During the day there are going to be times you are not using any power or at least very little power. For example if you are only using say 500 watts, and the panels are generating 2000 watts, you are sending 1500 watts out on the grid and the power is being used by your neighbors.

[SunEagle]

I have 2000 wat system. I will never generate more power than what my house uses. But It still decreases my bill. Do I need net metering?

I am curious as to how you were able to connect your system to the Grid without getting some type of net metering contract with the POCO.

Although some POCO's may not have a Net metering contract and refuse to pay you for the energy you generate but they can't charge you for that power.