Grid Tie Inverters and the Connections to Solar Panels?

How do solar panels attach to grid tie inverters? I cannot seem to find this information anywhere, and it is rather frustrating. Can anyone help me? Thank you!!

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  • 7 years ago
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    If you're trying to tie into the grid and don't already know to try looking at the inverter's datasheet from the manufacturer, you should consider getting someone else to wire it up for you.

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  • 7 years ago

    There are basically two kinds of inverters. Traditional, which have a string of many panels attached, and Micro, which have only one panel attached.

    Microinverters are simple to attach, and the panels may already have them underneath. The total solution tends to cost more, though.

    Traditional inverters rely on having many panels in series to develop a high voltage - perhaps between 200 and 500 volts in the US. There are positive and negative input terminals inside the inverter, and the wires carrying the voltage are screwed down to these. If there is not a cutoff switch included in the inverter, then an external one is wired in before the inverter.

    There are output terminals on the inverter, too. These are wired to a dedicated circuit breaker on the electrical service panel. Sometimes there is a cutoff switch wired between the inverter and service panel.

    If you're actually thinking of doing this yourself, do remember that house wiring is nothing to be trifled with. Get building permits and have inspections scheduled to insure you are conforming to the National Electrical Code.

    Source(s): Here is what we did http://pididu.com/solar/photovoltaic.html
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  • Anonymous
    7 years ago

    The generally attach either through the output connectors on the panel for micro-inverters, or through a series of panels wired together in series (often 8 to 12 panels). They use normal electrical wiring if they are not mounted together. The installation manual of an inverter will provide instructions on exactly where to connect in the inverter. Our company has installed well over 100 commercial and residential Solar Arrays.

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  • 4 years ago

    You have got to have the utilities permission to do so. They have to recognize that the inverter will synchronize to the utility's frequency and that after they shut energy off to the grid, might be to participate in protection, that your approach will not feed energy into the grid. In addition they ought to verify that the equipment and the workmanship meets their specifications. Simply purchasing off the self gear plugging it into your mains will get you into an international of main issue and liability. The sunlight panel most effective generates electrical energy when the sum is shining and this will not be if you end up utilising electricity. If it have been, then you possibly can be drawing less from the grid but usually, you must sell electrical power to the grid and buy it again from the grid and that means you must have a internet metering contract with them. In case you have an older analog power meter that might run backwards ( no longer all if them do ), you may be capable to get away with an unofficial hookup so long as your web usage when the meter is read does not lift any suspicions.

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  • Ecko
    Lv 7
    7 years ago

    Usually the inverter has a specification for voltage and current range. The panels need to produce voiltage and current in this range. The example panel below is intended for this purpose so each produces voltages from 60 volts with no load and 50 volts with maximum power output, so a maximum current is around 5 amps.

    Other ratings are for the maximum voltage (insulation) possibly 800V or more which limits the number of panels that can be in series (maxmum voltage) even if the inverter can use this voltage. A desireable feature is bypass diodes that improve behaviour with shading. Several series strings can be connected in parallel to increase the current according to overall piwer needs.

    As inverters may need several hundred volts it is normal to connnect several panels in series to obtain this voltage. The total power is the sum of the power from individual panels. The power is probably around 80% of the specification with full sun, mostly due to heating. Operating temperature is likely 50-60°C. Power is reduced further by the angle to the sun.

    Because the current and voltage levels produced by these panels are hazardous, several hundred volts at several amps, the installation should follow some recognized code of practice, and there may be regulations to comply with too. The panel outputs need special circuit breakers and isolators rated for DC like this, and outputs are often not grounded, but the frames and support structure should be bonded to ground for safety. There should be warning signs, and of course weather conditions like high wind must be catered for. Cable from panels to inverter needs to support the maximum voltage and current, being rated for outdoors in the sun and weather, and also provide some specified maximum voltage drop (to moderate losses). Generally all panels should be the same size and real efforts made to eliminate shading which can even damage panels. Ligttning protection could be an issue, and proper ventilation (behind the panels) is essential if they are to work in a suitable temperature range.

    The inverter manual in the second link (quoting the smaller model) shows that the voltage range for this unit should not exceed 600V, so an absolute maximum of 10 of the example panels in series. However the working range is 195 to 550V so minimum of 4 or maybe 5 panels and a maximum of 10 panels still holds. The maximum current is 15.4 amps, so up to 3 series strings can be connected in parallel. The maximum AC output to the grid is 2800W, which requires a suitable combination of voltage and current from the panels that exceeds thismm allowing for losses. This shows up as recommended 3070W to produce 2800W, implying efficiency at full power is 91%. With 2 series strings producing up to 10A total, the voltage determining the number of panels to get full output of the inverter is 3070W/10A = 307V. This represents just over 6 panels, so 7 panels per string would be better. This would allow for some additional losses. The inverter can probably deal with more power than is specified, so long as maximum voltage and current limits are not exceeded. Current drawn from panels by the inverter will be adjusted to suit.

    These are just off the cuff explanations to help with understanding.

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  • 3 years ago

    1

    Source(s): Guide To Solar Power : http://SolarPower.duebq.com/?ApM
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  • Rick
    Lv 7
    7 years ago

    If you don't know, you have no business doing it. The voltage and power levels involved are lethal.

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