SMA SUNNY ISLAND 3.0M User manual

QuickReferenceGuide
Off-Grid Systems with
SUNNYISLAND 3.0M / 4.4M / 6.0H / 8.0H
Off-Grid-IS-en-33 | Version 3.3ENGLISH

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Tel. [phone]
Fax [phone]
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Table of Contents
1 Information on this Document ..................................................................................................... 5
1.1 Validity .............................................................................................................................................................. 5
1.2 Content and Structure of this Document.......................................................................................................... 5
1.3 Target group ..................................................................................................................................................... 5
1.4 Additional Information...................................................................................................................................... 5
1.5 Symbols............................................................................................................................................................. 6
1.6 Typographies.................................................................................................................................................... 6
1.7 Nomenclature................................................................................................................................................... 6
2 Safety............................................................................................................................................. 7
2.1 Intended Use..................................................................................................................................................... 7
2.2 Safety Information ............................................................................................................................................ 7
3 Information and System Description........................................................................................... 11
3.1 Off-Grid System Functions................................................................................................................................ 11
3.2 Modular Design................................................................................................................................................ 12
3.2.1 Single System ................................................................................................................................................... 12
3.2.2 Single-Cluster System (Single-Phase) .............................................................................................................. 12
3.2.3 Single-Cluster System (Three-Phase)................................................................................................................ 13
3.2.4 Multicluster System........................................................................................................................................... 13
3.3 Information on Off-Grid Systems..................................................................................................................... 14
3.4 Optional Devices and Functions...................................................................................................................... 16
4 Single System................................................................................................................................ 18
4.1 Circuitry Overview............................................................................................................................................ 18
4.2 Connecting the Sunny Island Inverter.............................................................................................................. 19
4.3 Basic Configuration of the Sunny Island......................................................................................................... 21
5 Single-Cluster System ................................................................................................................... 24
5.1 Circuitry Overview Single-Phase Single-Cluster System................................................................................. 24
5.2 Circuitry Overview Three-Phase Single-Cluster System .................................................................................. 26
5.3 Connecting Sunny Island Inverters .................................................................................................................. 27
5.3.1 Connecting the Master .................................................................................................................................... 27
5.3.2 Connecting the Slaves ..................................................................................................................................... 29
5.4 Performing Basic Configuration of the Sunny Island...................................................................................... 30
6 Multicluster System....................................................................................................................... 34
6.1 Circuitry Overview and Connection of the Sunny Island Inverters................................................................ 34
6.2 Performing Basic Configuration of the Sunny Island in the Multicluster System........................................... 34
7 Commissioning.............................................................................................................................. 38
7.1 Switching to Installer Mode or Expert Mode ................................................................................................. 38
7.2 Commissioning the Multifunction Relays......................................................................................................... 38
7.3 Starting the System........................................................................................................................................... 38
7.4 Testing the Battery Current Sensor .................................................................................................................. 39
7.5 Testing the Generator....................................................................................................................................... 39
7.6 Testing the Load Shedding............................................................................................................................... 40
7.7 Commissioning the PV System ......................................................................................................................... 40
7.8 Testing Communication in the Multicluster System......................................................................................... 41
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7.9 Complete Commissioning. ............................................................................................................................... 41
8 Contact........................................................................................................................................... 42
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1 Information on this Document
1.1 Validity
This document is valid for off-grid systems with the following device types:
• SI3.0M-11 (SunnyIsland3.0M) with firmware version 3.2
• SI4.4M-11 (SunnyIsland4.4M) with firmware version 3.2
• SI6.0H-11 (SunnyIsland6.0H) with firmware version 3.1
• SI8.0H-11 (SunnyIsland8.0H) with firmware version 3.1
• MC-Box-6.3-11 (Multicluster-Box 6)
• MC-Box-12.3 (Multicluster-Box 12)
• MC-Box-36.3-11 (Multicluster-Box 36)
1.2 Content and Structure of this Document
This document summarizes the specific information on off-grid systems with SunnyIsland inverters. Circuitry overviews
of selected off-grid systems provide the basis as to how an off-grid system can be designed. The structure of the
document specifies the chronological sequence for configuration and commissioning. This document does not replace
the documentation of the individual products. You will find details and help in the event of difficulties in the
documentation of the respective product.
1.3 Target group
The tasks described in this document must only be performed by qualified persons. Qualified persons must have the
following skills:
• Training in how to deal with the dangers and risks associated with installing and using electrical devices and
batteries
• Training in the installation and commissioning of electrical devices
• Knowledge of and adherence to the local standards and directives
• Knowledge of and compliance with the documentation of the SunnyIsland inverter with all safety information
1.4 Additional Information
Links to additional information can be found at www.SMA-Solar.com:
Document title and content Document type
"SUNNY ISLAND System Guide - System Solutions for your Off-Grid Electricity
Supply"
Brochure
"Off-Grid Systems" Planning Guidelines
"PV Inverters in Off-Grid Systems" Technical Information
"Sunny Island Generator - Whitepaper" Technical File
"External Energy Sources" Technical Information
"Multicluster Systems with Stand-Alone Grid or Increased Self-Consumption and
Battery-Backup Function"
Installation Quick Reference
Guide
"Grounding in Off-Grid Systems" Technical Information
1 Information on this Document
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1.5 Symbols
Symbol Explanation
Indicates a hazardous situation which, if not avoided, will result in death or serious injury
Indicates a hazardous situation which, if not avoided, can result in death or serious injury
Indicates a hazardous situation which, if not avoided, can result in minor or moderate injury
Indicates a situation which, if not avoided, can result in property damage
Information that is important for a specific topic or goal, but is not safety-relevant
Indicates a requirement for meeting a specific goal
Desired result
A problem that might occur
1.6 Typographies
Typography Use Example
bold • Display messages
• Parameter
• Terminals
• Slots
• Elements to be selected
• Elements to be entered
• Connect the grounding
conductor to AC2Gen/
Grid.
• Select the parameter
235.01 GnAutoEna and
set to Off.
>• Several elements that are to be selected • Select 600# Direct Access
> Select Number.
[Button]
[Key]
• Button that is to be selected or clicked on • Select [Enter].
1.7 Nomenclature
Complete designation Designation in this document
SunnyBoy, SunnyMiniCentral, SunnyTripower PV inverter
Battery charge controllers not supplied by SMA Solar Technology AG Charge controllers from a third-
party supplier
Grid-forming generators such as electric generators or utility grids External energy sources
SunnyExplorer, SunnyPortal, SunnyHomeManager Communication product
The term "parameter" includes parameters with configurable values as well as parameters for displaying values.
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2 Safety
2.1 Intended Use
Off-grid systems with SunnyIsland inverters are self-sufficient utility grids that are being fed with energy from several
AC sources in the stand-alone grid (e.g., PV inverter), from a generator, and/or with DC charge controllers (e.g.,
SunnyIslandCharger). The SunnyIsland forms the stand-alone grid as a voltage source. The SunnyIsland regulates
the balance between the energy fed-in and energy used and has a management system with battery and generator
management and load control.
Off-grid systems with SunnyIsland are single-phase or three-phase AC distribution grids. The local standards and
provisions must be observed. Loads in off-grid systems are not protected against power failure.
The SunnyIsland is not suitable for supplying life-sustaining medical devices. A power outage must not lead to
personal injury.
Several SunnyIsland inverters can be operated in an off-grid system. Three SunnyIsland inverters are connected in
parallel on the DC side and form a cluster. The circuitry of the SunnyIsland inverters forming a cluster and the circuitry
of several clusters in a system must be carried out in accordance with this documentation (see Section3 "Information
and System Description", page11).
The SunnyIsland can synchronize with a generator and connect directly, if necessary. When the stand-alone grid is
connected to the generator, the voltage in the stand-alone grid is regulated by the generator.
The output power of the AC sources in the stand-alone grid is controlled via the frequency and voltage of the stand-
alone grid. The AC sources must be suitable for stand-alone mode with SunnyIsland (see technical information "PV
Inverters in Off-Grid Systems" at www.SMA-Solar.com). The maximum output power of the AC sources in a stand-
alone grid must be observed (see the SunnyIsland inverter installation manual).
The SunnyIsland uses batteries for energy storage. The nominal voltage of the battery must correspond to the input
voltage on the DC connection. A fuse switch-disconnector (e.g., BatFuse) must be installed between the battery and the
SunnyIsland. With lead-acid batteries, the battery room must be ventilated in accordance with the requirements of the
battery manufacturer and with the locally applicable standards and directives (see documentation of the battery
manufacturer).
If connecting a lithium-ion battery, the following must be observed:
• The lithium-ion battery must comply with the locally applicable standards and directives and be intrinsically safe.
• The battery management of the lithium-ion battery is compatible with the SunnyIsland (see the technical
information at "List of Approved Lithium-Ion Batteries").
In off-grid systems with lead-acid batteries only, a maximum of four SunnyIslandCharger charge controllers can be
connected per cluster. The battery management must record the DC current when charging and discharging the
battery. A battery current sensor may be installed to allow precise measurement of the battery current. The
SunnyIsland is not suitable for establishing a DC distribution grid.
Use this product only in accordance with the information provided in the enclosed documentation and with the locally
applicable standards and directives. Any other application may cause personal injury or property damage.
Alterations to the product, e.g. changes or modifications, are only permitted with the express written permission of
SMA Solar Technology AG. Unauthorized alterations will void guarantee and warranty claims and in most cases
terminate the operating license. SMA Solar Technology AG shall not be held liable for any damage caused by such
changes.
Any use of the product other than that described in the Intended Use section does not qualify as appropriate.
The enclosed documentation is an integral part of this product. Keep the documentation in a convenient place for
future reference and observe all instructions contained therein.
2.2 Safety Information
This section contains safety information that must be observed at all times when working on or with the product.
2 Safety
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To prevent personal injury and property damage and to ensure long-term operation of the product, read this section
carefully and observe all safety information at all times.
Danger to life from electric shock due to live voltage
High voltages are present in the off-grid system. When covers (e.g., an enclosure lid) are removed, live components
can be touched, which can result in death or serious injury due to electric shock.
• When carrying out any work on the electrical installation, wear suitable personal protective equipment.
• Switch off or disconnect the following components in the following order:
– Loads
– Generator
– SunnyIsland
– In the distribution board, the circuit breakers of the SunnyIsland inverter and of the generator.
– Load-break switch of the battery
• Ensure that the off-grid system cannot be reconnected.
• Open the enclosure lid on the SunnyIsland inverter and ensure that no voltage is present in the device.
• Ground and short-circuit the AC conductors outside the SunnyIsland inverter.
• Cover or isolate any adjacent live components.
Danger to life from electric shock due to damaged components
Operating a damaged component can lead to hazardous situations that can result in death or serious injuries due to
electric shock.
• Only use the off-grid system when it is technically faultless and in an operationally safe state.
• Regularly check the off-grid system for visible damages.
• Ensure that all safety equipment is freely accessible at all times.
• Make sure that all safety equipment is in good working order.
Danger to life from electric shock due to circuit breakers that cannot be tripped
In the stand-alone grid/battery-backup grid, only the circuit breakers that can be tripped by the SunnyIsland can be
tripped in the event of a grid failure. Circuit breakers with a higher operating current cannot be tripped. Under fault
conditions, a voltage that poses a danger to life may be present on accessible parts for several seconds. This can
result in death or serious injury.
• Check if a circuit breaker has a higher trip characteristic than the following circuit breakers which can be
tripped:
– SI3.0M-11 and SI4.4M-11: circuit breaker with trip characteristic B6 (B6A)
– SI6.0H-11 and SI8.0H-11: circuit breaker with trip characteristic B16 (B16A) or circuit breaker with trip
characteristic C6 (C6A)
• If a circuit breaker has a higher trip characteristic than the specified circuit breaker that can be tripped, you
should also install a residual-current device of type A.
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Danger to life due to incompatible lithium-ion battery
An incompatible lithium-ion battery can lead to a fire or an explosion. With incompatible lithium-ion batteries, it is not
ensured that battery management is intrinsically safe and will protect the battery.
• Verify that the battery complies with locally applicable standards and directives and is intrinsically safe.
• Ensure that the lithium-ion batteries are approved for use with the SunnyIsland (see technical information "List of
Approved Lithium-Ion Batteries" at www.SMA-Solar.com).
• If no lithium-ion batteries approved for the SunnyIsland can be used, lead-acid batteries can be used.
Danger to life due to explosive gases
Explosive gases may escape from the battery and cause an explosion. This can result in death or serious injury.
• Protect the battery environment from open flames, embers and sparks.
• Install, operate and maintain the battery in accordance with the manufacturer’s specifications.
• Do not heat the battery above the temperature permitted or burn the battery.
• Ensure that the battery room is sufficiently ventilated.
Chemical burns and poisoning due to battery electrolyte
If handled inappropriately, battery electrolyte can cause irritation to the eyes, respiratory system and skin, and it can
be toxic. This may result in blindness or serious chemical burns.
• Protect the battery enclosure against destruction.
• Do not open or deform the battery.
• Whenever working on the battery, wear suitable personal protective equipment such as rubber gloves, apron,
rubber boots and goggles.
• Rinse acid splashes thoroughly for a long time with clear water, and consult a doctor.
• If acid fumes have been inhaled, consult a doctor.
• Install, operate, maintain and dispose of the battery according to the manufacturer’s specifications.
Risk of injury due to short-circuit currents
Short-circuit currents in the battery can cause heat build-up and electric arcs. Burns or eye injuries due to flashes may
result.
• Remove watches, rings and other metal objects.
• Use insulated tools.
• Do not place tools or metal parts on the battery.
2 Safety
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Risk of crushing injuries due to moving PV array parts
Moving parts in the PV array can crush or sever body parts. A generator can be started automatically by the
SunnyIsland.
• Operate the generator only with the safety equipment.
• Carry out work on the generator in accordance with the manufacturer's specifications.
Risk of burns due to short-circuit currents on the disconnected SunnyIsland
The capacitors in the DC connection input area store energy. After the battery is isolated from the SunnyIsland,
battery voltage is still temporarily present at the DC connection. A short circuit at the DC terminal can lead to burns
and may damage the SunnyIsland inverter.
• Wait 15minutes before performing any work at the DC terminal or on the DC cables. This allows the capacitors
to discharge.
Damage to the battery due to incorrect settings
The set battery parameters influence the charging behavior of the SunnyIsland inverter. The battery can be
damaged by incorrect settings of the battery type, nominal voltage and capacity parameters.
• Ensure that the values recommended by the manufacturer are set for the battery (refer to the technical data of
the battery in the manufacturer documentation). Note that the battery charging behavior names used by
SMASolarTechnologyAG and the battery manufacturer may, in some cases, differ in meaning (for the battery
charging behavior of the SunnyIsland inverter, see technical information "List of Approved Lithium-Ion Batteries"
).
• Set the battery capacity for a ten-hour electric discharge (C10). The battery manufacturer specifies the battery
capacity in relation to discharge time.
Damage of components due to electrostatic discharges
If enclosure parts are removed, the devices (e.g. SunnyIsland or PV inverter) can be damaged or destroyed if
electronic components or terminals are touched.
• Do not touch any electronic components in open devices.
• Ground yourself before touching any terminals.
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3 Information and System Description
3.1 Off-Grid System Functions
Multicluster systems set up as off-grid systems can form self-sufficient utility grids fed with energy from multiple AC
sources in the stand-alone grid (e.g. PV inverter), from a grid-forming PV array and/or with DC charge controllers (e.g.
Sunny Island Charger). As a voltage source, the SunnyIsland inverter forms the stand-alone grid. The SunnyIsland
inverter regulates the balance between the energy that is fed in and the energy that is used and features a battery, PV
array and load management system.
Battery Management
Battery management of the SunnyIsland inverter is based on precise determination of the state of charge. By
combining the three most common methods for recording the state of charge, the SunnyIsland reaches a measuring
accuracy of more than 95%. This way, battery overcharge and deep discharge are avoided.
Another feature of battery management is the extremely gentle charging control. It automatically selects the optimum
charging strategy for the battery type and the situation in which it is used. This means that overcharging can be reliably
prevented and that the battery can be fully charged regularly. The available charge energy is used optimally at all
times (see technical information "Battery Management" at www.SMA-Solar.com).
Generator Management
The SunnyIsland can synchronize with a generator and connect directly, if necessary. When the stand-alone grid is
connected to the PV array, the voltage and frequency in the stand-alone grid are regulated by the PV array.
The SunnyIsland inverter generator management allows for uninterruptible connection of the stand-alone grid to the
generator and uninterruptible isolation from the generator. The generator management controls the generator via a
start and stop signal. A generator current control ensures that the generator always remains at the optimum operating
point. The generator management allows the use of generators that have a low output power in proportion to the
nominal load (see technical document "Sunny Island Generator - Whitepaper" at www.SMA-Solar.com)
Load Control
The load control enables control of the AC sources in stand-alone grids, control of a generator, and the specific
disconnection of loads.
The AC sources in the stand-alone grid are limited in their power output by the stand-alone grid frequency. In case of
excess energy, the load control system increases the power frequency. This limits the output power of the PV inverters,
for example.
If there is not enough energy available for all loads or the battery is to be preserved, load control can request energy
from a generator by means of the generator management. The generator management starts the generator and the off-
grid system is supplied with sufficient energy.
If no generator is present in the off-grid system or the energy is not sufficient despite the generator being available,
load control turns the loads off using load shedding. All loads are shed simultaneously with one-stage load shedding.
A load shedding contactor sheds the noncritical loads during the first stage with two-stage load shedding. The
remaining loads are shed during the second stage only when the state of charge declines further. This can further
increase the availability of the off-grid system for critical loads.
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3.2 Modular Design
3.2.1 Single System
Figure 1: Principle of a single system
In a single system, one SunnyIsland forms a single-phase stand-alone grid.
3.2.2 Single-Cluster System (Single-Phase)
Required device types for single-phase single-cluster systems
In single-phase single-cluster systems, the SunnyIsland inverters must be of device type SI6.0H-11 or SI8.0H-11.
Figure 2: Principle of a single-phase single-cluster system
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In a single-phase single-cluster system up to three Sunny Island inverters are connected to one battery forming a cluster.
The Sunny Island inverters are connected on the AC side to the same line conductor. If the device types within the
cluster are different, the master must be an SI8.0H-11.
3.2.3 Single-Cluster System (Three-Phase)
Figure 3: Block circuit diagram
In a three-phase single-cluster system up to three Sunny Island inverters are connected to one battery forming a cluster.
The Sunny Island inverters are connected on the AC side to three different line conductors.
A cluster that consists of different device types is only supported by SI6.0H-11 and SI8.0H-11. If the device types
within the cluster are different, the master must be an SI8.0H-11 (see Section3.3 "Information on Off-Grid Systems",
page14).
3.2.4 Multicluster System
Required device types for multicluster systems
In multicluster systems for stand-alone grids, the following device types must be used:
• SI6.0H-11 (SunnyIsland 6.0H)
• SI8.0H-11 (SunnyIsland 8.0H)
• MC-BOX-6.3-11 (Multicluster-Box 6)
• MC-BOX-12.3-20 (Multicluster-Box 12)
• MC-Box-36.3-11 (Multicluster-Box 36)
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Figure 4: Principle of a Multicluster-Box
Multicluster systems consist of several three-phase clusters. The individual clusters must be connected to a Multicluster-
Box. The Multicluster-Box is an SMA multicluster technology device for off-grid systems, battery-backup systems and
systems for increased self-consumption.
The Multicluster-Box is a main AC distribution board to which you can connect up to four clusters. Each three-phase
cluster is made up of three DC-side, parallel-switched SunnyIsland.
Only SunnyIsland inverters of the same device type may be installed in a cluster: SI6.0H-11 or SI8.0H-11.
3.3 Information on Off-Grid Systems
Information on Batteries
Lithium-ion batteries in off-grid systems
In order to meet the requirements of off-grid systems, the SunnyIsland has a high overload capacity. This overload
capacity is subject to the battery being able to supply sufficient current. With lithium-ion batteries, this ampacity cannot
be taken for granted.
• Check with the battery manufacturer whether the battery is suitable for off-grid systems with SunnyIsland inverters.
Pay special attention to the ampacity.
Recommendations for battery capacity
SMA Solar Technology AG recommends the following minimum battery capacities.
• Minimum battery capacity per SunnyIsland inverter:
– SI3.0M-11: 100Ah
– SI4.4M-11: 150Ah
– SI6.0H-11: 190Ah
– SI8.0H-11: 250Ah
• Minimum battery capacity per 1000Wp power of the PV system: 100Ah
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The sum of the individual battery capacities is the total minimum battery capacity and applies to a ten-hour electric
discharge (C10). The minimum battery capacity must be observed to ensure stable operation of the system.
Information on Clusters
Clusters in multicluster systems
Device type Potential device types
within a cluster
Explanation
SI3.0M-11 In all multicluster systems, the Sunny Island inverters must be device type SI6.0H-11 or SI8.0H-11.
SI4.4M-11
SI6.0H-11 SI6.0H-11 or SI8.0H-11 Only SunnyIsland inverters of the same device type may be installed
in a cluster: SI6.0H-11 or SI8.0H-11.
SI8.0H-11 SI6.0H-11 or SI8.0H-11
Clusters in three-phase single-cluster systems
Device type Potential device types
within a cluster
Explanation
SI3.0M-11 SI3.0M-11 A cluster must consist of the same device types.
SI4.4M-11 SI4.4M-11
SI6.0H-11 SI6.0H-11 or SI8.0H-11 A cluster can consist of one or both device types. If both device types
within the cluster are used, the master must be of device type
SI8.0H-11.
SI8.0H-11 SI6.0H-11 or SI8.0H-11
Clusters in single-phase single-cluster systems
Device type Potential device types
within a cluster
Explanation
SI3.0M-11 In single-phase single-cluster systems, the SunnyIsland inverters must be of device type SI6.0H-11
or SI8.0H-11.
SI4.4M-11
SI6.0H-11 SI6.0H-11 or SI8.0H-11 A cluster can consist of one or both device types. If both device types
within the cluster are used, the master must be of device type
SI8.0H-11.
SI8.0H-11 SI6.0H-11 or SI8.0H-11
Connecting the SunnyIsland inverters in single-phase single-cluster systems
In a single-phase single cluster system, the following cable lengths and conductor cross-sections must be designed the
same way:
• From the generator to each SunnyIsland
• From each SunnyIsland to the AC distribution board
• From the BatFuse to each SunnyIsland
The same design is a requirement for stable and symmetrical operation of the off-grid system.
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Information on the PV System
Maximum PV system power
In off-grid systems, the maximum PV system power depends on the total power of the Sunny Island inverters.
• Maximum output power of the PV system per SI3.0M-11: 4600W
• Maximum output power of the PV system per SI4.4M-11: 4600W
• Maximum output power of the PV system per SI6.0H-11: 9200W
• Maximum output power of the PV system per SI8.0H-11: 12000W
The maximum output power of the PV system must be observed to ensure stable operation of the off-grid system.
3.4 Optional Devices and Functions
The following devices can be used optionally in an off-grid system:
Component Description
Load-shedding contactor Contactor controlled by the SunnyIsland for isolation of loads
SunnyWebBox Remote monitoring and system configuration of the off-grid system
SunnyIslandCharger 50 Charge controller for off-grid systems with lead-acid batteries
A maximum of four SunnyIslandCharger charge controllers can be connected
to a cluster. In multicluster systems, four SunnyIslandCharger charge controllers
can be connected to each cluster. If lithium-ion batteries are used, no charge con-
trollers can be connected.
Battery current sensor Shunt for measuring the battery current
A battery current sensor is required in off-grid systems with DC loads or with
charge controllers from third-party suppliers (see Section2.1 "Intended Use",
page7).
SunnyIsland offers the following functions for off-grid systems via two multifunction relays (see the SunnyIsland
inverter installation manual):
Function Description
Controlling PV arrays A multifunction relay activates if a PV array request is received from the SunnyIs-
land inverter's generator management system. With the multifunction relay, you
can control PV arrays with an electrical remote-start function or connect a signal
generator for PV arrays with no autostart function.
Controlling load-shedding con-
tactors
A multifunction relay is activated depending on the state of charge of the battery.
Depending on the configuration, you can install a one-level load shedding with
one multifunction relay or a two-level load shedding with two multifunction relays.
You can also adjust the thresholds for the state of charge of the battery depend-
ing on the time of day.
Time control for external pro-
cesses
External processes can be time-controlled with a multifunction relay.
3 Information and System Description SMA Solar Technology AG
Quick Reference GuideOff-Grid-IS-en-3316

Function Description
Display of operating states and
warning messages
You can connect message devices to the multifunction relays to allow operating
states and warning messages from the SunnyIsland inverter to be output. One of
the following operating states and warning messages can be displayed for each
multifunction relay:
• The PV array is running and is connected.
• A SunnyIsland displays an error message of level 2 or higher. Only the
error messages within a cluster are evaluated here.
• A SunnyIsland displays a warning. Only the warnings within a cluster are
evaluated here.
• The SunnyIsland is in operation in a single system.
• The respective cluster is in operation in a cluster system.
• The SunnyIsland is in derating in a single system.
• The respective cluster is in derating in a cluster system.
Control of a battery-room fan The multifunction relay is activated when the charging current causes the battery
to emit gasses. A connected battery room fan is switched on for at least one
hour.
Control of an electrolyte pump Depending on the nominal energy throughput, the multifunction relay is activated
at least once a day.
Use of excess energy During the constant voltage phase, a multifunction relay is activated and thus
controls additional loads that can put any excess energy of AC sources in the
stand-alone grid (e.g., of a PV system) to good use.
3 Information and System Description
SMA Solar Technology AG
Quick Reference Guide 17Off-Grid-IS-en-33

4 Single System
4.1 Circuitry Overview
RCD2)
SUNNY
REMOTE CONTROL
SUNNY ISLAND CHARGER 50
BATFUSE-B.03
**
**
BatTmp +_
DC
N
AC1
Display
ComSyncOut
L
AC2 NPE LPE
ComSyncIn
SysCanIn
BackupVtgCur
Relay 2
Relay 1
NTT
ExtVtg BatVtgOut
DigIn
SysCanOut
L
N
_
+
ComETH
SUNNY PORTAL
SMA
CLUSTER
CONTROLLER
3)
3)
SWITCH/
HUB
PV ARRAY
AC LOADS
AC distribution board
PV INVERTER WITH
SPEEDWIRE INTERFACE
DC distribution board
optional
with SIC-PB communication interface
(up to 2 devices in parallel)
BATTERY
GENERATOR
1) If the SMA Cluster Controller shall be connected to Sunny Portal, a switch/hub must be added.
2) Whether a residual-current device (RCD) is required or not depends on the stand-alone grid
configuration and the grid-forming voltage sources (see technical information
“Grounding in Off-Grid Systems”).
3) DC-supplied contactor
ROUTER
optional1)
Figure 5: Single System
4 Single System SMA Solar Technology AG
Quick Reference GuideOff-Grid-IS-en-3318

4.2 Connecting the SunnyIsland Inverter
Figure 6: Connecting the SunnyIsland inverter
Position Designation Description / information
A AC power cable of the stand-alone
grid
SunnyIsland: connection to AC1Loads/SunnyBoys
terminals L, N, and grounding conductor
Conductor cross-section: maximum 16mm2
B AC power cable of the generator SunnyIsland: connection to AC2Gen/Grid terminals L,
N and grounding conductor
Conductor cross-section: maximum 16mm2
The SunnyIsland must be connected via a grounding
conductor on the terminal AC1 or AC2 to the ground po-
tential. The conductor cross-section of the grounding con-
ductor must be at least 10mm2. If the conductor cross-
section is smaller, an additional grounding conductor on
the enclosure with the conductor cross-section of the AC
power cable must connect the SunnyIsland with the
ground potential.
4 Single System
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Quick Reference Guide 19Off-Grid-IS-en-33

Position Designation Description / information
C DC+ cable Battery connection
Conductor cross-section: from 50mm2 to 95mm2
Cable diameters: 14mm to 25mm
Torque: 12Nm
D DC- cable
E Control cable, generator SunnyIsland: terminals Relay1NO and Relay1C
Conductor cross-section: from 0.2mm2 to 2.5mm2
F Measuring cable of the battery temper-
ature sensor
SunnyIsland: connection BatTmp
You only have to connect a battery temperature sensor if
lead-acid batteries are used.
Mount the battery temperature sensor in the middle of the
battery-storage system, in the upper third of the battery
cell.
G Control cable, load shedding SunnyIsland: connect the control cable to terminals Re-
lay2NO and BatVtgOut -.
Inside the SunnyIsland inverter, connect terminals Re-
lay2C and BatVtgOut+.
Conductor cross-section: from 0.2mm2 to 2.5mm2
H Speedwire network cable Terminal ComETH
In order to connect the router/network switch, the Speed-
wire data module SunnyIsland must be mounted in the
SunnyIsland (see SunnyIsland Speedwire data module
installation manual). The connection ComETH is on the
data module.
I Data cable to SunnyRemoteControl
display
SunnyIsland: terminal Display
K Data cable to SunnyIslandCharger SunnyIsland: terminal ComSyncIn
An additional data cable must be connected from the ter-
minal ComSyncOut to the battery only when lithium-ion
batteries are used. The communication bus must be
equipped with a terminator on both ends.
– Data cable to lithium-ion battery Only with lithium-ion batteries: additional data cable on
terminal ComSyncIn
4 Single System SMA Solar Technology AG
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