Requirements for the AC Connection
AC cable requirements:
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Aluminum or copper cables must be used.
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The conductors must be round conductors or 90 ° sector-shaped conductors.
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The conductors must be solid, stranded or fine-stranded. When using fine-stranded wire, bootlace ferrules must be used.
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Cable cross-section for round conductors: 50 mm² to 150 mm²
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Cable cross-section for sector-shaped conductors: 120 mm² or 150 mm²
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External diameter: 27 mm to 48 mm
Residual-current monitoring unit (RCMU):
The inverter is equipped with an all-pole sensitive residual-current monitoring unit in accordance with IEC/EN 62109-2 and VDE 0126-1-1. The all-pole sensitive residual-current monitoring unit monitors residual AC and DC currents. It disconnects the inverter redundantly from the utility grid in the event of residual current jumps of > 30 mA. Even if the residual current monitoring unit malfunctions, the inverter is immediately disconnected from the utility grid at all poles. The inverter therefore does not require an external residual-current device for safe operation. If local regulations require the use of a residual-current device, the following must be observed:
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The inverter is compatible with type B residual-current devices. For SHP 100-JP-20 the rated residual current must be 1000 mA and for SHP 143-JP-20 the rated residual current must be 1500 mA or higher (for information on selecting a residual-current device, see Technical Information "Criteria for Selecting a Residual-Current Device" under www.SMA-Solar.com). Each inverter in the system must be connected to the utility grid via a separate residual-current device.
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When using residual-current device with a lower rated residual current, there is a risk of false tripping of the residual-current device, depending on the system design.
Overvoltage category:
The inverter can be used in grids of overvoltage category III or lower in accordance with IEC 60664-1. That means that the inverter can be permanently connected to the grid-connection point of a building. In case of installations with long outdoor cabling routes, additional measures to reduce overvoltage category IV to overvoltage category III are required (see the Technical Information "Overvoltage Protection" at www.SMA-Solar.com).