Question on the 2000W Sun Grid Tie Inverter with Limiter with 240V output

Assuming you are in North America (Alberta, Canada?), you have 120/240 VAC split phase power.

Your utility meter will take care of accounting for the kWH being used/sent back to the utility. It works with Hot to Neutral loads (and backfeeding of current) and Hot to Hot loads (and backfeeding).

kWH is calculated as:

• Energy = kWH = Volts * Current * Time (Hours) * 1kWH/1,000 WH (divide by 1,000 to get "kilo")

Not an expert, but many (most) split phase utility meters for North America have "four clamps" for electrical connections. Two for L1/L2 in, and another two for L1/L2 to the home/main panel.

The meter measures the voltage (can only measure 240 VAC, Line to Neutral is assumed to be 240VAC/2=120 VAC nominal). And the meter measures the current in L1 and L2.

If you have 10 amps on L1 and 10 amps on L2 and zero current on the Neutral, that assumes that you have 10 Amps @ 240 VAC or 2,400 Watts (2.4kWatts).

If you have 5 amps on L1 and 10 amps on L2, then it is assumed that 5 amps is flowing on Neutral. So, you have 5 amps @ 240 vAC (1,200 Watts) and 5 amps on 120 VAC (600 Watts).

And similar, if you have 5 amps on L1 and 0 amps on L2, assume 5 amps on Neutral (Neutral is always the "difference between L1 and L2"), then you have 5 amps @ 120 VAC = 600 Watt.

The meter "knows" which direction the energy is flowing based on the phase between Voltage and Current...

Think of like peddling a tricycle... You push on the "forward pedal", you go forward. You push on the back pedal, and you slow down/go backwards.

The GT inverter "knows nothing" about your connected loads and if 120 or 240 VAC... It is just feeding energy back into your main panel. And Utility supplies the 120/240 VAC and "accepts" backfeed energy (like recharging a giant 240 VAC battery bank), or supplies energy when you are using more than you generate (discharging the giant 120/240 VAC utility battery).

And if you are wondering where the 120/240 Voltage/Current "magic" takes place, it is just the transformer on the pole outside your home. It has L1/Neutral/L2 connections and naturally "balances" current flow based on the loads (and your GT inverter output). The "input" to the transformer is something like 2,000 to 12,000 volts on two terminals for the other set of windings (left side of drawing below).

And there is always the question--Do you have an GT agreement with your utility and the proper meter installed?

The question is... Of course, the utility has the right to allow or refuse GT Inverter connections. They may ignore you, or "do something about it" (I have not heard of very many utilities that have pushed against "guerrilla GT inverter installs"--So I cannot tell you what may or may not happen).

Then there is the issue of using a "non-approved" GT Inverter installation....

In the very old days, the old mechanical meters would go "forward" if you bought power from the utility. And would go "backwards" if you generate power and feed it back to the utility.

These days, GT systems are not rare, and utilities are always looking for "flags" that help them identify people stealing electricity. And one of the common methods was to install the meter "upside down" for 1/2 the billing cycle to run the meter backwards to get "free power".

The modern electronic utility meters are programmed by the utility to behave they way they want/need/per PUC regulations. Old mechanical meters can have a "one way" clutch or ratchet installed. So... The meter may:

• Run forward when you buy power, run backwards when you sell power (and may flag the utility if power is being sold and not GT Plan). Of course, they have the option of different "registers" (one for buying kWH, another for selling kWH -- If different rates).
• Run forward when you buy power, not move when selling power.
• Run forward when you buy power, run forward when you sell power.
• Various other registers and functions are possible, and out there (my meter phones home once per hour so utility can charge me different rates for morning/afternoon/evenings/weekends--Time of Use TOU metering).

If you do not have a GT inverter rate plan/approved meter--You have to watch that you do not generate more power than you are using at any time... It is possible that your meter may charge you for feeding back into the utility (third bullet).

I do not know which GT Inverter you have, and you say it has a "limiter"... One of the most desired options wanted is a GT inverter that measures power usage by the home, and cranks back on the GT Inverter power output so that the energy never feeds back energy to the utility (for places were GT Inverters are not allowed--Common request).

-Bill

Bryan,

I have no experience, but hopefully somebody(ies) here has.

-Bill