SUNNY ISLAND 3324 / 4248 - Errata for installation guidefiles.sma.de/dl/5613/SI3324_4248-E-IEN094410.pdf · 2018-05-03 · This document replaces parts of Chapter 5 “Electrical

Installation Guide 1/16 SI3324_4248-E-IEN094410

Notes on this ManualThis document replaces parts of Chapter 5 “Electrical connection” of the Sunny Island 3324/4248 installation guide (document number: SI3324/4248-14:SE2406). Replace pages 31 to 44 and use this document as the installation guide.

1 Electrical Connection1.1 Safety Instructions

DANGER!Risk of lethal electric shock due to wrong connection.

• Only qualified personnel are permitted to install the electrical connections of the devices.

• All safety precautions listed here must be observed.

NOTICE!Electrostatic discharges can damage the Sunny Island.

Internal components of the Sunny Island can be irreparably damaged by electrostatic discharge.

• Ground yourself before touching a component.

SUNNY ISLAND 3324 / 4248Errata for installation guide

Version: 1.0 Mat. no.: 98-2013910

SMA Solar Technology AG Electrical Connection


1.2 Overview of the Connection Area

1.2.1 Interior ViewThe following figure provides an overview of all connections of the Sunny Island:

Enclosure openings on the Sunny IslandAll cables are fed through the enclosure openings on the bottom side of the Sunny Island and connected to the appropriate connection terminals on the inside.

Object DescriptionA Grounding (DC and AC)B DC connection (negative)C DC connection (positive)D AC output (stand-alone grid)E AC input (generator or grid)F additional connection terminals (e.g. communication, control relays)G Interface slot for Piggy-Back



1.2.2 Exterior ViewAll cables are fed through the enclosure openings on the bottom side of the Sunny Island and connected to the appropriate connection terminals on the inside.

Metric-thread Cable Screw ConnectionUse the metric-thread cable screw connections and fasten the AC cables inside the Sunny Island enclosure in a manner conforming to the appropriate standards. The metric-thread cable screw connections guarantee a dust-free and waterproof installation of the cables in the enclosure and also provide strain relief for the cable connection.If properly installed, the terminals and cable feed-through seals guarantee IP30 protection.

Object DescriptionA DC connection (negative)B DC connection (positive)C AC output (stand-alone grid)D AC output (generator or grid)E GroundingF additional connection terminals (e.g. communication, control relays)G Battery Current Sensor



1.3 DC connection

1.3.1 Check Connection RequirementsConnecting the BatteryConnect a suitable battery to the DC side. The DC connection must be established in observance of all applicable regulations (e.g., DIN EN 50272-2, "Safety Requirements for Batteries and Battery Systems - Part 2: Stationary Batteries").

Cable Protection

WARNING!Risk of burns or even death due to arcing and short-circuiting when connecting the battery.

• Follow all safety and maintenance instructions provided by the battery manufacturer.• Use special (insulated) tools to mount and install the battery.• Make sure the cross-section of the cables is adequate and the polarity of the cables

leading to the battery is correct.

WARNING!Risk of lethal electric shock.

The internal DC circuit breaker of the Sunny Island 3324/4248 is designed such that it can interrupt currents of up to 10 kA.If no external cable protection (load-disconnecting switch) exists, then the DC cables must be protected against ground faults and short circuits.

• In addition to the DC circuit breaker, install a BatFuse (external DC fuse) between the Sunny Island 3324/4248 and the battery as a cable protection and load disconnection unit.

• Mount the fuse in accordance with the information provided in the installation guide for the BatFuse and in accordance with the cable cross-sections used.

NOTICE!Function impairment of devices on the DC side

The Sunny Island is NOT suitable for use with DC supply grids.Function impairment can occur on devices installed on the DC side of a Sunny Island with cables exceeding 30 meters and with a flexible connection.

• Only use fixed installations.• Do not use cables of lengths greater than 30 meters between the Sunny Island and

the battery and/or DC device.



SMA Solar Technology offers the following external DC fuses:

1.3.2 Grounding

Calculating the Required Grounding Cable Cross-sectionSMA Solar Technology cannot state generally valid values for the cross-section of the cable required for the external grounding of the battery. The cable dimensions depend on the type and size of the battery connected, the external fuse (DC side) and the material used in the grounding cable.

The required cross-section of a (copper) grounding cable can be calculated using the following formula. Trigger times for short-circuit currents of between 2,000 A and 10,000 A are typically about 25 ms.

A grounding cable of 16 mm² cross-section is thus adequate for short-circuit currents up to 10,000 A.

BATFUSE-B.01-2 Battery connection box for a Sunny Island 4248 with fuse switch disconnector (NH01 200 A)

BATFUSE-B.01-3 Battery connection box for a Sunny Island 3324 with fuse switch disconnector (NH01 250 A)

DC cablesThe DC cables should be as short as possible (always < 30 m). Since high currents flow through the battery cables, they can become very warm. Long cables and insufficient cable cross-sections reduce the system efficiency as well as the overload capabilities.

• Do not lay the battery cable under plaster or in armored plastic pipes. • Use both DC negative and both DC positive connection terminals for the DC

connection.

External grounding• External grounding of the negative pole of the batteries is possible, because the

batteries and the grid side are galvanically isolated within the Sunny Island. In this case, make sure that the high currents that may occur under fault conditions can be adequately discharged.

• If a ground connection is necessary, it must be established separately by an installer outside of the Sunny Island.

• When grounding the battery, the Sunny Island's enclosure must be additionally grounded, also in the DC area.

Determining the cross-sectionExact calculation of the grounding cable cross-section must take account of the regionally applicable standards and guidelines.

t = interruption time in secondsISC = maximum battery current (short-circuit current) in AS = cable cross-section in mm2



Grounding Sunny Island

1. Assemble metric-thread cable screw connection M20 on enclosure opening E (see diagram on page 3).

2. Provide protective conductor with suitable cable end sleeve.3. Thread the protective conductor through the cable screw connection in the enclosure.4. Insert the protective conductor with cable end sleeve into the ground connection terminal and

tighten the screw firmly (torque 4.0 Nm to 5.7 Nm).5. Tighten metric-thread cable screw connection.☑ Sunny Island is grounded.



1.3.3 Connecting the Sunny Island on the DC SideCable SizingMount a DC cable that at least corresponds to the battery charging nominal current of the Sunny Island:

SMA Solar Technology recommends mounting a cable in accordance with the following:

ConnectionIn the Sunny Island there are two "DC–" and two "DC+" connections for the battery cable for cable end sleeves of 35 mm2 each.

Sunny Island Battery charging nominal current Cable SizingSI 3324 160 A at least 2 x 16 mm2

SI 4248 100 A at least 1 x 35 mm2

Sunny Island Cable Permissible up to...SI 3324 2 x 25 mm2 200 ASI 4248 1 x 35 mm2 125 A



Allow for the fact that the connection terminals for the 2 "DC –" cables are arranged above each other and slightly concealed. Procedure for the connection:1. Assemble metric-thread cable screw connections

on enclosure opening A and B (see diagram on page 3).

2. Provide DC cables with suitable cable end sleeves.

3. Thread 2 "DC –" cables through the cable screw connections A (see diagram on page 3) into the enclosure.

4. Thread 2 "DC +" cables through the cable screw connections B (see diagram on page 3) into the enclosure.

5. Insert first "DC –" cable with cable end sleeve into the lower "DC –" connection terminal (1) and tighten the screw firmly (torque 4.0 Nm to 5.7 Nm).

6. Insert second "DC –" cable with cable end sleeve into the upper "DC –" connection terminal (2) and tighten the screw firmly (torque 4.0 Nm to 5.7 Nm).

7. Then insert the "DC +" cables with cable end sleeves into the "DC +" connection terminals and tighten the screws firmly (torque 4.0 Nm to 5.7 Nm).

8. Tighten the counter nut of the metric-thread cable screw connection.

☑ The DC connection of the Sunny Island is installed.

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DConly

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DConly

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DCductors only

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1.4 AC ConnectionConnect the Sunny Island through a sub-distribution to the stand-alone grid (loads, PV generator (Sunny Boy), wind turbine system (Windy Boy) and to any other external sources (generator, grid)).

1.4.1 Check Connection RequirementsGrounding

Provide the protective conductor with with suitable cable end sleeves and connect to the PE terminals in the AC connection area of the Sunny Island.Fusing of the Sub-distribution

Use cables with a maximum cross-section of 16 mm² for the AC installation The AC nominal current is 14 A for the Sunny Island 3324 and 18 A for the Sunny Island 4248.

TN systemWhen working with public grids, the Sunny Island may only be installed as a TN system.In stand-alone configurations, the (protective) ground of the Sunny Island and its individual components must be wired as a TN system only. All valid standards and guidelines must be taken into account.

CAUTION!Risk of injury due to high discharge currents against PE.

The N cable of the Sunny Island has NOT been connected with PE by default. • Ground the stand-alone grid system on the AC side before commissioning outside of

the Sunny Island.• For safety reasons (discharge currents exceeding 3.5 mA), use either two protective

conductors (redundant grounding) or a protective conductor of at least 10 mm².

DANGER!Danger to life due to residual currents.

• Protect all users with a residual current breaker (RCD) or, for the Sunny Island 4248, protect with a 16 A circuit breaker with B tripping characteristic.

No all-pole isolatorThe Sunny Island is not disconnected on all poles: the neutral conductor (N conductor) is looped through the device and the N connection terminals of "AC output" and "AC input" are connected inside the device.



1.4.2 Connecting the AC Output

Connect, with three wires via the sub-distribution, for example, loads, PV generators (Sunny Boy) and wind turbine systems (Windy Boy), to the Sunny Island's AC output (C) connection.

1. Assemble metric-thread cable screw connections on enclosure opening C (see diagram on page 3).

2. Thread the three-wire AC cable through the terminal.3. Provide the three wires of the AC cable with suitable cable end sleeves.4. Connect PE, N and L cables according to the labeling in the AC output terminal (torque 2.0 Nm

to 4.0 Nm). L and N must not be swapped.

5. Tighten the counter nut of the metric-thread cable screw connection.☑ The AC output of the Sunny Island is installed.

Cable ProtectionSMA Solar Technology recommends the use of a line circuit breaker (B type, max. 16 A). This has the following advantages:

• The cable cross-section is dimensioned based on the value of 1 x nominal current.• For maintenance work, the Sunny Island can be switched off via the line circuit

breaker on the stand-alone grid side.

Position DescriptionC AC output (stand-alone grid) – labeling of the terminal: "AC OUTPUT"D AC input (generator/grid) – labeling of the terminal: "AC INPUT"



1.4.3 Connecting the AC InputConnect, with three wires via the distribution, the generator or the public grid to the Sunny Island's AC input (D).

Wire the AC input as described in section 1.4.2 "Connecting the AC Output" (page 10).

DANGER!Danger to life due to residual currents and ungrounded neutral conductor.

• Ground the grid-side PEN conductor within the system (before or at the point of separation into N and PE conductors e.g., the connection from the house's junction box to the equipotential bonding rail).

NOTICE!Device damage due to high currents.

A maximum of 56 A should flow through the Sunny Island's AC input. • Install a line circuit breaker on the grid side to protect the Sunny Island against

overcurrents. • For maintenance work, the Sunny Island can be switched off via the line circuit

breaker on the grid side.Transfer relay in the Sunny IslandThe transfer relay in the Sunny Island connects the phase L-AC input with the L-AC output. The transfer relay is interconnected for a switched off device and attached grid voltage. It functions like a break contact.No RCD circuit breaker with 30 mA in grid-side supplyDo not install an RCD circuit breaker with 30 mA in the grid-side supply, as this could erroneously trip the supply due to the discharge currents of the Sunny Island against earth.



1.5 Additional ConnectionsFor installing the connections described below (battery temperature sensor, control relays, communication, etc), either one cable with an external diameter between 7 mm and 14 mm, or two cables with an external diameter of 6 mm each, may be used for each enclosure opening on the underside of the enclosure.The following diagram provides an overview of the connection terminals. The two terminal strips for the connections are arranged offset above each other.

Position DescriptionA Control relays: "Start generator" (G_Req)B Control relays: "Load shedding" (Load_S)C Response signal: "Generator has been started" (G_Run)D Battery temperature sensor (TBat)E Device fans (FAN)F Communication: RS232 or RS485



1.5.1 Connecting Device FansThe Sunny Island 3324/4248 has fans allowing the device to constantly feed heavy loads even at high ambient temperatures. The fans are located in the rear of the enclosure (not illustrated) and are already connected on delivery.







Documents

SUNNY ISLAND 3324 / 4248 - Errata for installation guidefiles.sma.de/dl/5613/SI3324_4248-E-IEN094410.pdf · 2018-05-03 · This document replaces parts of Chapter 5 “Electrical