sunny string monitor - cabinet (ssm-c)the sunny string monitor cabinet (ssm-c) enables connection of...

Sunny String Monitor - Cabinet (SSM-C)Installation and use of the SSM-C

Technical Description Version 1.0 SSMC-TEN07231098-4000210

SMA Technologie AG

Technical Description SSMC-TEN072310 Seite 1

Index

1 Notes on this Manual. . . . . . . . . . . . . . . . . . . . . . 31.1 Validity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.2 Target Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.3 Explanation of the Symbols Used . . . . . . . . . . . . . . . 3

2 Description of the Sunny String Monitor Cabinet . 5

3 General Safety Instructions . . . . . . . . . . . . . . . . . 73.1 Appropriate Usage. . . . . . . . . . . . . . . . . . . . . . . . . 73.2 Personnel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73.3 About this Manual . . . . . . . . . . . . . . . . . . . . . . . . . 73.4 Checking the Delivery . . . . . . . . . . . . . . . . . . . . . . . 83.5 Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83.6 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83.7 Special Hazards of Photovoltaic Systems . . . . . . . . . 83.8 Special Hazards of Grounded PV Systems . . . . . . . . 93.9 Cabling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103.10 Electrical Connection . . . . . . . . . . . . . . . . . . . . . . 103.11 Disconnection. . . . . . . . . . . . . . . . . . . . . . . . . . . . 113.12 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133.13 Commissioning, Maintenance and Repair . . . . . . . . 133.14 General Information . . . . . . . . . . . . . . . . . . . . . . . 13

4 Parallel Connection of Strings . . . . . . . . . . . . . . 144.1 Maximum Number of Strings per Measurement Input 144.2 Reverse Current . . . . . . . . . . . . . . . . . . . . . . . . . . 14

5 Structure of the SSM-C . . . . . . . . . . . . . . . . . . . . 16

6 Installing the Floor-mounted Distribution Board . 18

SMA Technologie AG

Seite 2 SSMC-TEN072310 Technical Description

7 Connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217.1 Connection of the DC String Lines . . . . . . . . . . . . . 217.2 Connection of the DC Main Lines . . . . . . . . . . . . . . 227.3 Ground Connection . . . . . . . . . . . . . . . . . . . . . . . 237.4 RS485 and Power Supply Connections. . . . . . . . . . 247.4.1 Cable Type for the Data Line. . . . . . . . . . . . . . . . . . . . . . . . . .247.4.2 Shield Contact Connection . . . . . . . . . . . . . . . . . . . . . . . . . . .247.4.3 Data Line Connection in the SSM-C . . . . . . . . . . . . . . . . . . . . .257.4.4 SSM-C Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .267.4.5 Connection in the Sunny Central . . . . . . . . . . . . . . . . . . . . . . .28

8 Configuration of the Sunny Central . . . . . . . . . . 328.1 Sunny Data Control . . . . . . . . . . . . . . . . . . . . . . . 328.2 Serial Interface Settings . . . . . . . . . . . . . . . . . . . . . 328.3 Detection of SSM-Cs . . . . . . . . . . . . . . . . . . . . . . . 338.3.1 Registration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .338.3.2 Detection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .338.3.3 Setting the Device Address . . . . . . . . . . . . . . . . . . . . . . . . . . .35

8.4 Deleting Detected SSM-Cs. . . . . . . . . . . . . . . . . . . 37

9 String Current Monitoring Function . . . . . . . . . . 389.1 Activation of String Current Monitoring . . . . . . . . . . 389.2 Polling Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . 389.3 Error Sum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

10 Setting String Current Monitoring Parameters . . 4110.1 Triggering Time . . . . . . . . . . . . . . . . . . . . . . . . . . 4110.2 Tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4210.3 Configuring Groups . . . . . . . . . . . . . . . . . . . . . . . 4310.4 Setting the Number of Strings . . . . . . . . . . . . . . . . 4510.5 Time Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . 4710.6 Overnight Shutdown Setting . . . . . . . . . . . . . . . . . 50

SMA Technologie AG

Technical Description SSMC-TEN072310 Seite 3

10.7 Setting the Anti-Theft Protection. . . . . . . . . . . . . . . . 51

11 Values of the String Current Monitoring System 5311.1 Groups' Mean Values . . . . . . . . . . . . . . . . . . . . . . 5311.2 Measured Values of the Measuring Channels . . . . . 54

12 Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5512.1 Active Warnings. . . . . . . . . . . . . . . . . . . . . . . . . . 5512.2 Warnings History . . . . . . . . . . . . . . . . . . . . . . . . . 55

13 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . 5613.1 Problems when Detecting the SSMs . . . . . . . . . . . . 56

14 Contact. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

SMA Technologie AG Notes on this Manual

Technical Description SSM-TEN072310 Page 3

1 Notes on this Manual

1.1 ValidityThis documentation describes how to install and operate a Sunny String MonitorCabinet (SSM-C).

1.2 Target GroupThis documentation is intended for installers and operators of PV systems which arerealized with the SSM-C. It includes a description of how to install, operate andmaintain the SSM-C, as well as troubleshooting with the aid of the Sunny Data Controlsoftware and the data logger Sunny Central Control.

1.3 Explanation of the Symbols UsedIn this document, the following terms and symbols are used to describe different hazardlevels:

DANGER!

DANGER indicates a hazardous situation which, if not avoided, will result indeath or serious injury.

WARNING!

WARNING indicates a hazardous situation which, if not avoided, could resultin death or serious injury.

CAUTION!

CAUTION indicates a hazardous situation which, if not avoided, could resultin minor or moderate injury.

NOTICE!

NOTICE indicates a situation that can result in property damage if notavoided.

Notes on this Manual SMA Technologie AG

Page 4 SSM-TEN072310 Technical Description

Information

Information provides tips that are valuable for the optimal installation andoperation of your product.

Storage of handbooks

This operating manual, the installation guide, the data sheets, the operatingmanuals of installed components, and the wiring diagrams must be kept in theimmediate vicinity of the Sunny Central. They must be available to operatorsand maintenance staff at all times.

SMA Technologie AG Description of the Sunny String Monitor Cabinet


2 Description of the Sunny String Monitor CabinetThe Sunny String Monitor Cabinet (SSM-C) enables connection of several strings inparallel. If failures occur in individual modules, or in the string cabling, they can onlybe detected with great effort, or not at all. The SSM-C reliably detects failures, and thusprevents power losses and yield losses.In addition, the SSM-C enables monitoring of the internal overvoltage protectors. Theyare integrated into each SSM-C in order to protect the inverter from transientovervoltages. The upstream string fuses allow defective strings, e.g. with a short circuitin a module or the cabling, to be isolated from the entire PV array. If a string fuse istriggered, this is detected by the software, and a warning is generated in the SunnyCentral Control (SCC), which is situated within the Sunny Central (SC). In addition, theindividual string currents are analyzed and displayed in the SCC.For maintenance work and the connection of string lines, there are isolation terminalsin the SSM-C, which enable load-free disconnection of the individual connected strings,or all connected strings, from the PV generator. An optional load-disconnecting switchis available, which realizes disconnection from the inverter. See the block circuitdiagram of the SSM-C below.

Data transfer to the SCC occurs via an RS485 bus. The +55 V supply comes from theSunny Central.

Overvoltage protection

RS485 +55 V

Sunny String Monitor Cabinet

Stringcurrent monitoring

Sunny Central

SunnyCentral

Control via hub

Load disconnector

Description of the Sunny String Monitor Cabinet SMA Technologie AG


Essential differences to the previous Sunny String Monitor:• Measurement in the negative and positive lines by means of variant configuration• Only suitable for grounded systems• Suitable for 1000 V DC• Night operation possible for anti-theft protection• Star-shaped RS485 wiring, with a maximum individual length of 1000 m• Better troubleshooting and commissioning in the field due to star-shaped wiring• Improved communication quality due to maximum of 5 participants per bus• SSM-C power supply with safety extra-low voltage from the hub in the SC• Communication and power supply are incorporated in one cable

SMA Technologie AG General Safety Instructions


3 General Safety InstructionsFailures that affect or limit the safety of the device must be rectified immediately.Unauthorized modifications and the use of spare parts not recommended by SMATechnologie AG may cause fire, material damage and electrical shock. Unauthorizedpersonnel must not have access to the equipment.Warning signs must always be clearly readable and immediately replaced if damaged.

3.1 Appropriate UsageAppropriate use of the SSM-C means following all instructions in the manual relating toinstallation, electrical connection, and commissioning of the equipment.Any deviation from the instructions in this manual is regarded as inappropriate use ofthe equipment. SMA Technologie AG accepts no responsibility or liability for any andall damage resulting from inappropriate use of the equipment.Appropriate use of the equipment also entails the following:• Observation of the safety instructions listed here and in the following sections• Observation of the instructions in the Sunny Central installation guide and user

manual• Conformance to the device-dependent technical dataAdherence to the additional notes for Sunny Central M/P inverters for groundedoperation of the PV generator

3.2 PersonnelOnly qualified technical personnel may perform any and all work on the SSM-C."Qualified" means that the personnel must possess training relevant to the activityperformed and must be familiar with the content of this manual. The personnel musthave read and understood the safety section in this manual.

3.3 About this ManualThis manual was written with the greatest possible care. However, discrepancies cannotbe excluded. SMA Technologie AG accepts no responsibility or liability for injury topersons, or material damage caused by mistakes in this manual.

General Safety Instructions SMA Technologie AG


3.4 Checking the DeliveryOn receipt of the equipment, check the packaging and the device for any possibledamage and compare the contents of the delivery with the delivery documentation. Inthe case of damage to the device and/or unclear delivery contents, contact SMATechnologie AG immediately (contact address is in the appendix).

3.5 StorageThe SSM-C may only be stored in rooms protected from dust and moisture.

3.6 InstallationThe requirements relating to the installation location, the manner of installation and themounting position must be observed.In addition to this, the following points must be noted:

• The installation location must be easily accessible and offer a secure base forworking on the device.

• The connection cables must be connected to the internal strain-relief clamp in thebase in order to prevent exertion of mechanical strain on the housing.

• Interference testing occurred as per DIN EN 61000; accordingly, the installationlocation must be in an area where EMI fields are slight.

The SSM-C is built using the latest technology, and according to recognized safetystandards. Despite this, a fault resulting in arcing cannot be ruled out (see section 3.7"Special Hazards of Photovoltaic Systems", page 11).This can result in melting of the housing as well as fire and smoke, which represents ahazard to personnel or equipment. This must be taken into consideration uponinstallation.

• The equipment may not be installed near to inflammable materials. If this cannotbe avoided, preventative measures must be taken, which prevent fire and smokefrom spreading.

• The equipment may not be installed in critical areas, escape routes, living spacesor office spaces.

3.7 Special Hazards of Photovoltaic SystemsDANGER!Risk of lethal electric shock

An active power source is connected!



Photovoltaic systems have special characteristics representing special hazards that aredescribed here.An active power source is connected, which means that depending on the operatingmode there may be voltage present, from the photovoltaic generator and/or the SunnyCentral. This is especially important to note when disconnecting the Sunny StringMonitor's floor-mounted distribution board.Very high DC voltages are present (no zero-crossing) that, in the case of a fault orinappropriate use of fuses or plugs, may lead to arcing.The short-circuit current of the photovoltaic generator is only slightly higher than themaximum operating current and is also dependent on the level of solar radiation, whichmeans that if a short circuit occurs in the system, the existing circuit breakers are notguaranteed to switch off.A highly branched generator array may be difficult to disconnect if a fault develops(e.g. short circuit). We recommend the additional use of the optionally available DCcircuit breaker for disconnecting the inverter.

3.8 Special Hazards of Grounded PV SystemsThe positive or negative pole of the PV generator is grounded within the Sunny Centralvia a GFDI fuse (GFDI: ground fault detection interruption).

The grounding of the PV generator can be interrupted automatically by the GFDI at anytime.

NOTICE!

Additional grounding within the PV generator or floor-mounted distributionboard is not permissible!

NOTICE!

Refer to the additional notes for Sunny Central M/P inverters for groundedoperation of the PV generator.

CAUTION!

The GFDI does not ensure personal protection, but merely system protection!



3.9 CablingWith regard to the SSM-C cabling, it must be ensured that the data lines and the DCmain lines are laid separately. The distance between these two lines should be > 1 m.In the event of damage to the high voltage line, dangerous voltages can couple intothe cable shield.In addition, the data line's cable shield must be connected at both ends, i.e. in the SCand in the SSM-C.

3.10 Electrical ConnectionThe electrical connection must be performed according to this manual and the device'stechnical data.

DC Power Supply

Insertion of the string fuses and connection of the isolation terminals causes the DCvoltage of the connected strings to become available in the device.The string fuses may only be inserted when the following conditions are satisfied:• All connections are made according to this manual• The load-disconnecting switch is deactivated, and the isolation terminals are open• The DC main lines are connected to the inverter or DC distribution box and are

isolated (no reverse voltage is possible from the inverter).• The polarity of the DC voltages at the string inputs has been checked, and there is

no short circuit present• The strings have been checked with an insulation test to ensure that there is no

ground fault

NOTICE!

When cabling, ensure that the DC main lines and the data line are laidseparately.

WARNING!

The equipotential bonding must be connected!



3.11 Disconnection

The SSM-C must be disconnected for working at the SSM-C and at the SMU boards.The device must be disconnected on both sides, i.e. the DC main lines to the SC via theload-disconnecting switch, and the connected strings via the isolation terminals for PVplus and PV minus. If there is no DC circuit breaker on the floor-mounted distributionboard, the DC fuses in the Sunny Central must be pulled in order to avoid reversevoltage from the inverter.Work carried out on the SMU board which, for example, involves unplugging the plugconnectors or removing the string fuses, is strictly only permissible under voltage-freeconditions.

WARNING!

If the isolation terminals are closed, the lower fuse holders are also energizedwhen the string fuse is disconnected!The Plexiglas covers must always be mounted, to ensure protection againstaccidental touching!

WARNING!

Before inserting the string fuses, the correct polarity and ground fault protectionmust be ensured. The fuses may only be inserted or removed under load-freeconditions and using the appropriate personal protective equipment.

WARNING!

The isolation terminals may only be closed or opened under load-freeconditions.

WARNING!

Be careful of reverse voltage from the inverter!



Capacitor Discharge TimeThe device contains capacitors that discharge slowly when the device is disconnected.There are dangerous accidental-contact voltages present in the device immediatelyafter switching off. If there is a fault in the device, these voltages may also remainpresent for a longer period of time. For this reason, always check that the device isvoltage-free before working on it.

Information

We recommend the use of DC circuit breakers (optionally available) forisolating the inverter or the SSM-C. Even in the case of faults or fire, this allowssystem components to be isolated safely.

Information

Work on the SSM-C may be performed only after switching off the power tothe unit. The VDE regulations must be followed.• Disconnect the device• Protect against reenergizing• Test each unit to ensure that all voltages have been removed• If necessary, cover or protect against accidental contact with any voltage-

carrying components.

WARNING!

If the isolation terminals are closed, the lower fuse holders are also energizedwhen the string fuse is disconnected!

CAUTION!

The discharge time of the capacitors is longer than 5 minutes.



3.12 OperationApart from the optionally available DC circuit breaker, and the isolation terminals forPV plus and PV minus, there are no other control elements on the floor-mounteddistribution board. Setting of parameters and querying of measurements occurs over theRS485 serial interface. The device must only be opened for commissioning,maintenance and troubleshooting. Observe the following safety instructions for workingon the device.

3.13 Commissioning, Maintenance and RepairAll work on the SSM-C may only be performed when the device is safely disconnectedfrom the PV voltage, when the device is secured against accidental restarting, and whenthe device has been checked to be voltage-free. Only qualified technical personnel,who are familiar with the operation of the system, may undertake any such work.During maintenance, the ventilation plates on the housing must be checked annually fordirt. This is necessary so that pressure equalization in the housing can continue, and sothat moisture cannot accumulate in the housing.

3.14 General InformationBurnsImmediately after isolating the device, depending on the operating conditions, certaincomponents can be very hot (e.g. fuses).

CAUTION!

We recommend that safety gloves be worn during all work on the device.

Parallel Connection of Strings SMA Technologie AG


4 Parallel Connection of Strings

4.1 Maximum Number of Strings per Measurement InputWhile the SSM-C is able to connect several strings in parallel, the analysis in the SCCis, however, limited to a maximum of nine, with a tolerance setting of 10 %. Themaximum number of strings which can be connected in parallel in order to achievereliable analysis in the SCC depends on the adjustable tolerance, and can bedetermined as follows:

N = maximum number of strings which can be connected in parallel.The parameter "tolerance" can be adjusted in the SCC.

4.2 Reverse CurrentIn contrast to the "Sunny Boy" string inverters, in the PV generator of a system using theSunny Central, e.g. using thin-film modules, many strings are connected in parallel. Themaximum number of connected strings depends on the module type, and thus must berequested from the module manufacturer. Short circuits can cause wrongly directed module current, leading to a string beingsubjected to so-called reverse current, which may be considerably higher than thenormal maximum current (short circuit) of the string. Thus, the string fuses protect thefaulty string. The largest permissible string fuse depends on the module type, and mustbe selected in accordance with its defined curve.In principle, reverse current can only occur when modules are connected in paralleland the open circuit terminal voltage (Voc) of the individual parallel strings is different.In normal operation, this is avoided adequately when the strings are of the same length.Since shadowing of the modules has no significant effect on Uoc, even in this situationno significant reverse current occurs.In failure-free operation of a correctly dimensioned PV generator, no excessive reversecurrent can occur! Reverse current can only occur due to a fault in the solar generator (e.g. short circuit inone or more modules) that causes the open circuit terminal voltage of a module stringto be significantly lower than the open circuit terminal voltage of other parallel strings.

N = 0.9 / tolerance (%)

Information

The maximum number of strings which can be connected in parallel is limitedto nine, if the tolerance is set to 10 %.Thus, if the number of strings connected in parallel is larger than nine, failureof a string cannot be registered or identified in the SCC.

SMA Technologie AG Parallel Connection of Strings


In the worst case, the voltage on the faulty string may lie within the MPP voltage (UMPP)of the remaining generator elements. The internal diode structure of the solar cells thencauses reverse current to flow through the faulty generator string that, depending on theamount of current, may lead to excessive heating or destruction of the modules in thisstring!Among other symptoms, the following faults may lead to reduction of the open circuitterminal voltage of a generator string and subsequent reverse current in parallel-connected systems:

• Short circuit in one or more modules• Short circuit in one or more cells in a module• Double ground fault in a module and/or the cabling

Despite the fact that these faults are very unlikely, and extremely rare in practice,preventative measures must still be taken. After all, these types of faults carry a highpotential for damage and danger, since all modules in the affected string may bedamaged and the local heating may also cause secondary damage. Thus, it is nosurprise that these issues have long been taken into consideration by the UL(Underwriters Laboratories Inc.) certifiers in the USA and the reverse current ratings area standard specification in US data sheets for PV modules.On the basis of these potential problems, the SSM-C contains fuses that isolate thedefective strings from the rest of the PV array. When a string fuse is triggered due to afault in a module, the software detects this and a warning is generated.

-

+ L

N

Current in the faulty string – total current of the remaining strings

Structure of the SSM-C SMA Technologie AG


5 Structure of the SSM-CDepending on the chosen option, the SSM-C can be equipped with a load-disconnecting switch, and various numbers of string connections. The selection of SSM-C options or fittings can occur via the option code in the price list. This also defines thestructure and identification of the SSM-C.The following diagram gives a schematic overview of the various components andconnection points inside the Sunny String Monitor Cabinet with the cover removed:

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A B C A B C D E

F G H F I KJ ML

D

SMA Technologie AG Structure of the SSM-C


Depending on the selected fittings, the interior view of an SSM-C can differ from themaximum assembly options.For the connection of RS485 communication, and for the +55 V DC power supply,terminals are provided in the connection area. In addition, the connection areaprovides a contact for the data line's cable shield.The connection of string lines can be realized by means of the isolation terminals, toenable load-free disconnection of the individual strings, or all strings, from the solargenerator. String monitoring occurs via the SMU board in the SSM-C, on which a dataprocessing Piggy-Back (SMU8HV-DVPB) is integrated. The SMU8HV-DVPB realizes themanagement of string currents and the SMU board's parameter settings. For connectionof the DC main lines to the inverter, two bolt clamps are integrated within the SSM-C. The load-disconnecting switch provides the option of disconnecting the SSM-C on theinverter side. The busbar is necessary for grounded operation, in which the respectivePV pole (negative or positive) is grounded in the inverter. For protection from transientovervoltages caused by lightning strikes, overvoltage protectors are built into the SSM-C. A grounding terminal is provided for connection of the equipotential bonding.

A Communication Piggy-Back

B Jumper for communication

C Data processing Piggy-Back

D LEDs for display of operating mode

E DC switch

F DC fuses

G Communication socket

H DC string connections: + pole

I DC main line: + pole

J Ground connection

K Overvoltage protectors

L DC string connections: - pole

M DC main line: - pole

Installing the Floor-mounted Distribution Board SMA Technologie AG


6 Installing the Floor-mounted Distribution BoardThe SSM-C can be installed directly outdoors. Thus, the lengths of the DC string linescan be minimized reducing the losses on the DC side.

In the case of a rack-mounted solar generator, the SSM-Cs can ideally be positioneddirectly behind the generator in the shadow. Here, make sure that no rain flows overthe housing from the module surface.The connection cables must berouted into the housing's interior in asealed manner, in order to ensureprotection rating IP54.Thus, it is also imperative to couplethe connection cables to theintegrated strain-relief clamp in thebase so that the weight of thecables cannot exert any mechanicalstrain on the housing. This also isnecessary for the IP54 protectiondegree to be guaranteed.

NOTICE!

Ensure that no moisture is enclosed within the housing when installing the SSM-C. An installation in rain or high air humidity can result in a failure or evendamage of the electronics in later operation!

NOTICE!

Select the installation location so that the SSM-C is protected from direct solarradiation, and is freely accessible for maintenance work.

SMA Technologie AG Installing the Floor-mounted Distribution Board


The maximum burial depth for the base is 600 mm. To fill the base, one half (300 mm)must be filled with gravel or sand (grain size 2 - 4 mm), and the rest with so-called "basefiller" or coarse gravel (grain size 4 - 8 mm).

Information

When installing the SSM-C, observe the installation guide which is provided inthe base.

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Coarse gravel (base filler)4 - 8 mm

Gravel or sand2 - 4 mm

Installing the Floor-mounted Distribution Board SMA Technologie AG


When burying, ensure that 1/4 of the second front panel remains visible. The first frontpanel should be freely accessible as it must be possible to remove this for any retrofittingwork, or in the event of failure.

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SMA Technologie AG Connection


7 Connection

7.1 Connection of the DC String LinesThe connection of the string lines is realized by means of the isolation terminals on themounting plate. To this end, the individual string lines must be routed into the housing'sinterior in a sealed manner. To connect the string lines, a suitable screwdriver with a5.5 x 0.8 mm blade must be used so as not to damage the terminals. To ensure a secureconnection between the string lines and the spring-type terminals, 12 mm of insulationmust be stripped from the string lines before they are fed into the isolation terminals. Notstripping the required length can lead to poor connections that may damage the SSM-C.

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28

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U8

HV

-DV

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Ms60-DC8FS

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

+

Z2-X

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

DC string lines: + pole DC string lines: - pole

Connection SMA Technologie AG


7.2 Connection of the DC Main LinesConnection of the DC main lines is realized by means of cable lugs at the provided boltclamps. To this end, both DC main lines, like the string lines, must be routed into thehousing's interior in a sealed manner. Each connection to the two bolt clamps is to beclamped with a nut and appropriated cable lug.

NOTICE!

See that the terminal screws are tightened!

1 2 3 4 5 6

Z9-X

9

L+

L+

Z2-X

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

L-

L-

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L+

12

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L-

12

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L+F

A2

06

47

06

00

02

37

4V

ers

.: A1

485H

CV

BP

-01

11

31

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.:A

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/N1728

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B

Ms60-DC8FS

FA

20

64

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-01

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DC main line: + pole DC main line: - pole



7.3 Ground ConnectionIn order to guarantee the functioning of the integrated overvoltage protectors, it ismandatory to connect them to the external ground! To this end, a grounding cable (min.16 mm²) is connected to the grounding terminal (see below) and grounded in thevicinity of the SSM-C (ground rod or similar).

1 2 3 4 5 6

Z9-X

9

Z2-X

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L+

12

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L-

12

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L+

FA

2064706

0002374

Vers

.: A1

485H

CV

BP

-01

1131

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.:A

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SM

U8

HV

-DV

PB

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FA

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0002374

Vers

.: A1

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CV

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-01

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.:A

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/N1728

SM

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HV

-DV

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L+

L+

L-

L-

L+



7.4 RS485 and Power Supply Connections

7.4.1 Cable Type for the Data LineConnection of the RS485 bus and the +55 V DC power supply in the SSM-C is to berealized by means of a single cable. The corresponding cable type must contain eightwires as twisted pairs, and have a minimum cross-section of 0.5 mm² (4 x 2 x 0.5 mm²).This is necessary because the +55 V DC power supply requires four of the cable'sconductors, with two conductors used in parallel in each case, in order to guarantee acable cross-section of 1 mm². For communication, however, only two conductors arerequired: data + and data -. The remaining two wires are used as reserves.

7.4.2 Shield Contact ConnectionThe cable shield must be connected to the provided shield rails in the inverter and SSM-C. The shield clamps can accept cables up to a maximum diameter of 8 mm. Handlingof the shield clamps is pictured below. The shield clamps must only be hand-tightened.Never use a screwdriver. Screwing the shield clamps with a screwdriver can damagethe insulation.

Information

The cable type Li-2YCYv is recommended!

NOTICE!

Do not screw in the shield clamps with a screwdriver, hand-tighten only!



7.4.3 Data Line Connection in the SSM-C

Connection of the data line occurs at the connection terminals in the SSM-C. To this end,a suitable screwdriver with a 5.5 x 0.8 mm blade must be used so as not to damagethe terminals. To ensure a secure connection between the data line and the spring-typeterminal, 12 mm of insulation must be stripped from the data line before it is fed into theconnection terminals. Not stripping the required length can lead to a poor connectionthat may damage the SSM-C.The wiring between the individual SSM-Cs is realized in a bus, upon observation of theterminal assignments.

WARNING!

All SSM-Cs in the string must be disconnected via the load-disconnectingswitches and the isolation terminals before connecting the data line.If there is no circuit breaker in the SSM-C, the DC fuses in the SC must be pulledin order to avoid reverse voltage from the inverter.Only after this has taken place may cabling work be carried out on the SSM-C.

1 2 3 4 5 6

Z9-X

9

L+

L+

Z2-X

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

L-

L-

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L+

12

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L-

12

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L+

1 2 3 4 5 6

Z9-X

9

L+

L+

Z2-X

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

L-

L-

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L+

12

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L-

12

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L+

1 2 3 4 5 6

Z9-X

9

L+

L+

Z2-X

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

L-

L-

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L+

12

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L-

12

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L+



7.4.4 SSM-C TerminationWith RS485 cabling, the last SSM-C of each string must be terminated. Upon delivery,the SMU boards in the respective SSM-Cs are not terminated so that free configurationof the SSM-Cs can be performed on site. The SSM-Cs are connected to the SC in series,and depending on the number, flow into one or two hubs.

String MonitorPower Supply Unit / Hub

FUSE

LL

NN

NCPEPE

AC

+55VSSM Power

SCC

Data-Data+GNDGND+55V+55V

SSM

RS485OUT

RS485IN

U1-A6

www.SMA.de

SunnyCentral

Central

Sunny

ControlENTER

ESC


FUSE

LL

NN

NCPEPE

AC

+55VSSM Power

SCC


SSM

RS485OUT

RS485IN

U1-A6

www.SMA.de


FUSE

LL

NN

NCPEPE

AC

+55VSSM Power

SCC


SSM

RS485OUT

RS485IN

U1-A6

www.SMA.de

SunnyCentral

Central

Sunny

ControlENTER

ESC

Sunny Central

Sunny Central

SSM-C series

SSM-C series

Terminated

Not terminated

Terminated

Not terminated



The jumper must be mounted on one SMU board so that the termination is activated.

Termination is realized by means of:1. Mounting the jumper on an SMU board in the last SSM-C2. Removing the other jumpers on the SMU boards in the respective SSM-C3. Plugging the termination resistor into the RJ45 socket "485 Out" at the SMU8 hub

power supply unit (default configuration)

1 2 3 4 5 6

Z9-X

9

L+

L+

Z2-X

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

L-

L-

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L+

12

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L-

12

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L+

Jumper mountedJumper not mounted



Termination with Team ConfigurationIn a Team configuration, the termination resistor must be removed from the RJ45 socket"485 Out" at the SMU8 hub power supply unit in the SC, and replaced by the providedCAT5 cable. The cabling for a Team configuration is shown in the figure below.

7.4.5 Connection in the Sunny CentralConnection of the data line in the SC occurs at the X4 plug of the SMU8 hub powersupply unit. This power supply unit provides the +55 V DC supply voltage, and theconnection of the RS485 bus for the SSM-C.The maximum number of SSM-Cs which can be connected to an SMU8 hub powersupply unit is limited to 5.In each case, the cabling from the power supply unit is realized in a bus (see RS485and supply voltage wiring plan on the following page). For each SSM-C (except forthe last SSM-C), the two RS485 data lines and the four power supply lines are to beconnected in the connection area, in observation of the terminal assignments in theSSM-C.


FUSE

LL

NN

NCPEPE

AC

+55VSSM Power

SCC


SSM

RS485OUT

RS485IN

U1-A6

www.SMA.de


FUSE

LL

NN

NCPEPE

AC

+55VSSM Power

SCC


SSM

RS485OUT

RS485IN

U1-A6

www.SMA.de

SunnyCentral

Central

Sunny

ControlENTER

ESC

SunnyCentral

Central

Sunny

ControlENTER

ESC




FUSE

LL

NN

NCPEPE

AC

+55V

SSM

Power

SCC


SSM

RS485OUT

RS485IN

U1-A6

www.SMA.de

1 2 3 4 5 6

Z9-X

9

L+

L+

Z2-X

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

L-

L-

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L+

12

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L-

12

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L+

Sunny

Centra

l

CentralSunny

ControlENTERESC



Noting the Serial NumberAfter completion of installation work, and before connecting the DC voltage, youshould make a note of the serial numbers of the data processing Piggy-Back (DVPB-SMU8HV). This is important for settings made later at the SCC, and for the grouping ofthe individual SMU boards in the SSM-C.

NOTICE!

The serial number of the data processing Piggy-Back (SMU8HV-DVPB) mustnot be confused with the serial number on the white name plate situated on themounting plate.

1 2 3 4 5 6

Z9-X

9

L+

L+Z2

-X2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

L-

L-

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L+

12

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L-

12

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L+

FA

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64

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After connection of the power supply for the SSM-C, it is possible to check that thecabling is correct in that the LEDs on the SMU board glow as described below.

LED 1 (green)Overvoltage protector

Glows: overvoltage protector 1 ok

LED 2 (green)Digital input (optional anti-theft protection)

Glows: digital input / anti-theft protection ok

LED 3 (orange)Data transfer

glows if data transfer is active

LED 4 (red)Board fault

Glows: fault on the string current monitoring system'scontrol board

1 2 3 4 5 6

Z9-X

9

L+

L+

Z2-X

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

L-

L-

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L+

12

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L-

12

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L+

FA

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1 2 3 4

Configuration of the Sunny Central SMA Technologie AG


8 Configuration of the Sunny CentralPassword ProtectionIn order to configure the SSM-C in the SCC, it is necessary to enter the installerpassword!

8.1 Sunny Data ControlIn general, the SSM-C can be configured using a PC and Sunny Data Control (SDC).SDC can be downloaded at www.SMA.de for free. Details on the use of SDC are available in the technical description of SDC.

8.2 Serial Interface SettingsThe COM1 interface must be configured at the SCC. Select the menu "Device Set-up" and the corresponding submenu "Interfaces". The menu item"Communication" allows editing of the COM1 interface.

"Device Set-up...Interfaces...Communication...COM1 SMUs"

Settings:

Information

This installation guide describes direct configuration at the SCC by means ofthe control buttons. Configuration of the SCC using SDC is explained by meansof several examples.

[ COM1:SMUs ]

‡Medium...

...RS485

Baudrate... Š

...19200 Baud

Protocol...

...SMA-Net

Medium In general, for the SSM-Cs, RS485 is to be set as transfer medium betweenthe Sunny Central and the individual SSM-Cs.

Baudrate 19200 baud

Protocol SMA-Net

SMA Technologie AG Configuration of the Sunny Central


8.3 Detection of SSM-Cs"Device Set-up...SMUs...Devices"

All SSM-C settings can be made here.

Before detection, make sure that no SSM-Cs have yet been detected, by means of the"Registration" menu item.

8.3.1 Registration"Device Set-up...SMUs...Devices...Registration"

8.3.2 Detection"Device Set-up...SMUs...Devices...Detection"

When the "Detection" menu item is selected, the SCC automatically starts thedetection of new devices. After the devices have been detected, the new devices mustbe accepted and saved. Under the menu item "Registration", check whether all serial numbers of the dataprocessing Piggy-Backs (SMU8HV-DVPB) from the respective SSM-Cs' SMU boardsare registered correctly. Each serial number found must match the actual serial numberon the DVPBHV-SMU8 (see the section entitled "Noting the Serial Number", page 32).If it is not the case that all of the existing SMU boards are included in the registration,the detection process can be repeated.

[ SMU Devices ]

Registration

Detection

Parameters Š

Measured Values

Information

There must be no entries here. If entries are present, delete all detected devices(see also section 8.4 "Deleting Detected SSM-Cs", page 40)!

Information

If problems arise regarding detection of the SMU boards, read section 13!



If SDC is being used, the system must be detected again within SDC after the SCC hasdetected the SMU boards. This is necessary for the devices to be visible in SDC's onlinedisplay. Detection via SDC only functions correctly after the SCC has first detected allSMU boards.

Detection with Team ConfigurationIn a Team configuration, detection of the respective SSM-Cs' SMU boards must occurat the Team leader. In Team mode, the Team leader is responsible for all string currentmonitoring and analysis. Consequently, string current monitoring parameters are set atthe Team leader's SCC.



Checking the DetectionThe serial numbers found must match the actual serial numbers on the SMU8HV-DVPB(see figure below).

8.3.3 Setting the Device AddressFor identification of the individual SMU boards in the SSM-C, the device address "SSMIdentifier" must be set. The "SSM Identifier" is not the network address whichis automatically assigned upon detection.Every SMU board in the SSM-C must be allocated a unique identifier between 1 and40. This is necessary so that upon occurrence of a fault, the SMU board in the SSM-Ccan be located precisely, and analysis can occur in the SCC. This makestroubleshooting easier, for example, in the event of a string failure, or a deviating string.

Information

If no "SSM Identifier“ is set, it is not possible for the SCC to determinewhich of the SSM-C's SMU boards has the PV array fault.

NOTICE!

The maximum "SSM Identifier“ number which can be managed from theSCC is limited to 40. If "SSM Identifier“ is set > 40, analysis thereof is notpossible in the SCC.



The "SSM Identifier" setting is adjusted in the SSC's "Parameters" menu for therespective detected serial number."Device Set-up...SMUs...Devices...Parameters"

"SSM Identifier" can also be set directly in SDC's SMU parameters. This allows theindividual devices to be selectively allocated in sequence in the PV array.

[ Parameters]

SW version

.............2.03

SSM Identifier

............2



8.4 Deleting Detected SSM-CsIt is also possible to delete SMU8HV-DVPB serial numbers which have already beenregistered for each SMU board. This is done by changing the ID number to 99. The IDnumber can be changed via the "Registration" menu item."Device Set-up...SMUs...Devices...Registration"

Information

Select the serial number to be deleted in the menu and confirm by pressing the[Enter] button. Change the device ID to 99 and confirm the deletion of theserial number. After quitting the menu, confirm acceptance of the changes.

String Current Monitoring Function SMA Technologie AG


9 String Current Monitoring FunctionThe string currents are continually recorded by the respective data processing Piggy-Back (SMU8HV-DVPB) on the SMU board in the SSM-C, and averaged over a timeperiod of 30 seconds. A mean value for each measuring channel is transferred to theSSC at 5 minute intervals. In the SSC, a mean value is calculated for all queriedmeasuring channels which belong to a group. If a measuring channel deviates from themean value of the group by more than the (adjustable) tolerance setting, this deviationis added to a sum at 5 minute intervals. If the sum of the deviations exceeds theinternally calculated error sum, then a warning is displayed.The mean values of the measuring channels and groups can be recorded at the SSCfor documentation or information purposes.

9.1 Activation of String Current MonitoringIf power levels or string currents are very low, monitoring is impractical. Thus, stringcurrent monitoring only becomes active if the DC power exceeds 5 % of the SC'snominal AC power, and if the average string current of the individual groups is greaterthan or equal to 0.5 A.

9.2 Polling IntervalThe mean values of the measuring channels of each SMU board in the SSM-C arecyclically transferred to the SSC every 5 minutes. When setting parameters in the SSC,it can therefore happen that the function of newly set parameters is first applied afterabout 5 minutes. The communication between the SSM-Cs and the SSC is kept to anabsolute minimum to avoid interference in the communication occurring on the busbetween Team leader and Team member.

9.3 Error SumThe SSM-C is able to distinguish between temporary fluctuations in solar radiation andreal faults, and only indicates faults that have actually occurred (e.g. total failure of astring). The deviations of each measuring channel that are higher than the set tolerance aretotaled, measuring channel by measuring channel, at a polling interval of 5 minutes,and error sums are created for every individual measuring channel. The error sum iscalculated based on the set tolerance value and the triggering time.Calculation of the error sum:

An example will be used to illustrate the measuring process and the error sumcalculations in more detail.

Error sum (%) = Triggering time (min) x Tolerance (%) / 5 min

SMA Technologie AG String Current Monitoring Function


The dependence of the error sum on the tolerance setting and the triggering time isillustrated in the figure below.

When setting the parameters for the two values of triggering time and tolerance, youshould assume a static mean value. The main point to consider is after what time apredefined deviation of a measuring channel from the group mean value should berecognized.

Example:It is assumed that at t0 the mean value of a group is 5 A. All string currents are nowcompared to this mean value. If no string current lies outside the set tolerance of (e.g.)10 % (i.e. 5.5 A), totaling is not performed.If, however, a string shows a string current of 6 A, then the difference between theactual string current (6 A) and the tolerance limit (5.5 A) is added to the total. Thedifference is thus 0.5 A, which is a deviation of 10 % from the mean value. Thisdifference of 10 % is now added to the total until the error sum is reached. Assumingthat the string current lies at 6 A for a longer period of time, and the triggering time isset to 10 minutes, then the error sum can be calculated as follows:

Error sum (%) = Triggering time x Tolerance (%) / Polling interval

Error sum = 10 min x 10 % / 5 min = 20 %

50 10 15 20 25

5 A

Tolerance limit at 10 % = 5.5 A

Cycle time [min]

Mea

n cu

rren

t val

ue [A

]

Totaling begins since the tolerance limit has been

exceeded

The difference, which is totaled until the fault limit is reached

Actual string current = 6 A

String Current Monitoring Function SMA Technologie AG


Based on the calculation in this example, a value of 20 % is calculated for the errorsum. In this manner, the current difference of 0.5 A, which equates to a deviation of 10% of the mean value, is added to the total for each polling interval of 5 minutes, untilthe error sum of 20 % is reached. In this example, the error sum is reached after twopolling intervals, i.e. 10 minutes, which is the triggering time, and thus a warningmessage is displayed in the Sunny Central.The submenu "SMUs...Failure" shows which Sunny String Monitors and whichmeasuring channels deviate excessively from the group mean value. Upon confirmationat the SSC, the error sum is reset, and the warning disappears from the display.If a string fails completely, the current difference in the above example is 4.5 A, whichequates to a deviation of 90 % from the mean value. If the settings in the aboveexample remain the same, i.e. tolerance at 10 % and triggering time at 10 minutes, theerror sum of 20 % is already reached after the first Sunny Central polling interval (5minutes). The Sunny Central now displays the warning "SMU".On the basis of this example and the calculation formula, the sensitivity of the stringcurrent monitoring can now be set by using the two parameters triggering time andtolerance. If you have questions relating to the correct parameter settings for the Sunny StringMonitor, you can contact SMA directly on the Sunny Central Serviceline. The telephonenumber can be found in section 14 of this user manual.The adjustable parameters are described in the following sections.Activate the submenu "SMUs" from the menu "Device Set-up". All settingsregarding all of the connected SSM-Cs can be made here. The parameters concerningstring current monitoring can be set in the submenu "SMU Parameters".

SMA Technologie AG Setting String Current Monitoring Parameters


10 Setting String Current Monitoring Parameters

10.1 Triggering TimeThe triggering time is the time between the first occurrence of a failure at a measuringchannel (deviation of string current outside the tolerance) and the display of a warningat the SCC, with an assumed constant tolerance. The triggering time can also affect thesensitivity of the string current monitoring system as it is included in the calculation of theerror sum. The triggering time is an adjustable value in the SCC, with a default settingof 180 minutes.

"Device Set-up...SMUs...Parameters"

The triggering time can also be set directly in SDC as a parameter of the SCC.

[SMU Parameters]

Reg. SMUs

........3.SMUs

ErrorReportTime

........180 min Š

Setting String Current Monitoring Parameters SMA Technologie AG


10.2 ToleranceThe individual string currents are detected per group and compared with the meanvalue of the group. The string current may only deviate from the group mean value byup to a maximum of the set tolerance (in % of the group mean value). If the toleranceis exceeded, then the excess value is totaled. This occurs at every polling interval of 5minutes.A tolerance value between 10 and 100 % of the group’s mean value must be definedfor each group.

The tolerance value can be set via the menu item "tolerance grp 1 - 3" of the menu "SMUParameters".


Information

As essentially only a clear deviation of a measuring channel from a meanvalue is an indication of a faulty string, while minor deviations can beconsidered as to be normal, the tolerance value should be set accordingly high(e.g. 10 % or 20 %).

[SMU Parameters]

tolerance grp1

..........10 %

tolerance grp2

..........10 %



The tolerance of the individual groups can also be set directly in the Sunny Data ControlSCC parameters.

10.3 Configuring GroupsThe SCC is able to subdivide the individual measuring channels of the connected SMUsinto three groups to make it possible to compare just measuring channels which havethe same properties (orientation, radiation, shadowing). The groups are monitoredindependently of each other, and each individual measuring channel can be allocatedto a group in a freely selectable manner.

Information

An individual group must include at least four measuring channels.



The allocation of the individual measuring channels to the different groups is set directly,using the SMU parameters in the SCC:

"Device Set-up...SMUs...Devices...Parameters"

[ Parameters]

Group Channel 8

...1

Group all chan.

...2 Š

Information

Each individual measuring channel of an SMU can be allocated to a group ina freely selectable manner. Under "Group all chan.", all measuringchannels of the SMU are allocated to one group. This avoids having toallocate the individual measuring channels to a group as this then occursautomatically for all the individual measuring channels.

Information

If individual measuring channels of the SMU are not to be included in the stringcurrent monitoring system, then these should be allocated to group zero, sincestring current monitoring is deactivated for this group.



The allocation of the individual measuring channels to the different groups can also beset directly in SDC, using the SMU parameters.

Group Classification with Team ConfigurationWith the Team configuration, the SSM-C must be subdivided into at least two groups,and the SSM-Cs which are connected to the Team leader must be monitored in onegroup (e.g. group 1). The SSM-Cs which are connected to the Team member are alsomonitored in a separate group (e.g. group 2). This subdivision is necessary so that if afault arises at the Team member, no warnings appear at the Team leader's SCC.

10.4 Setting the Number of Strings

Information

The intended maximum number of strings assigned to a measuring channel istwo. However, depending on the system design, more strings can beconnected in parallel outside the SSM-C, and added to a measuring channel.To this end, see section 4 "Parallel Connection of Strings", page 17.



Under "Device Set-up...SMUs...Devices...Parameters", the number ofconnected strings per measuring channel used can be entered.


[ Parameters]

No.of Strings 1

......2

No.of Str. All

......1

Information

The number of strings per channel is freely selectable for the eight measuringchannels. The default setting is 1. The maximum number of strings is limited to4.

Information

Under "No.of Str. All", all channels of the SSM-C can be given a stringcount of one to four. This avoids having to set the number of strings for each ofthe individual channels, since this is automatically set for all the individualchannels.

Information

If no strings are attached to a measuring channel, this channel must beallocated to group zero, since the string current monitoring is deactivated forthis group. This is necessary to ensure that this measuring channel is notincluded in the averaging process.



The number of the individual strings per measuring channel can also be set directly inSunny Data Control by means of the SMU parameters.

10.5 Time WindowsIn order to filter out temporary effects (e.g. shadowing in the morning, etc) on anindividual string, it is possible to define a time window for every individual channel ofthe SSM-C. For each time window, the defined string will only be monitored after thetime defined in ("Monitoring On"). The time windows are defined in the "SMU Parameters" submenu:

[ Parameters]

Monitoring6 On

.......0.00

Monitoring6 Off

.......0.00

Monitoring On

.......0.00

Monitoring Off

.......0.00




Information

Exactly one time window can be defined per measuring channel.

On The time of day when monitoring of the respective measuring channel is to startis entered here.

Off The time of day when monitoring of the respective measuring channel is to stopis entered here.

Information

A specific time window for string current monitoring can be entered for everyindividual measuring channel of the SSM-C.

Information

Under "Monitoring On" / "Monitoring Off", a particular string currentmonitoring time window can be defined for the entire SSM-C.



The time windows of the individual strings for each measuring channel can also be setdirectly in Sunny Data Control by means of the SMU parameters.



10.6 Overnight Shutdown SettingDue to the +55 V power supply, the SCC provides the option of overnight shutdown.In the default settings, overnight shutdown is activated in the SC ("ON"). Thus, thepower supply to the SSM-Cs is deactivated in the SC as soon as the PV voltage hasbeen < 250 V for one hour. The power supply is activated as soon as the PV voltageof 250 V is reached.Upon deactivation of the overnight shutdown, the SSM-C continues to be supplied withpower during the night. This provides the option of activation and analysis of the anti-theft protection (see section 10.7 "Setting the Anti-Theft Protection", page 54).Under "Device Set-up…SMUs…Parameters", the overnight shutdown for the floor-mounted distribution boards can be activated and deactivated.


The overnight shutdown can also be set directly in Sunny Data Control via the SCCparameters.

[ Parameters]

Overnight

shutdown

....on

Anti-theft

protection

.....off

Information

Overnight shutdown, and the anti-theft protection described in the followingsection, are only available with SCC software version V6.07 and above.



10.7 Setting the Anti-Theft ProtectionThe SSC provides the option of activating the anti-theft protection. To this end, alarmcontact 2 on the SMU8HV must be incorporated into the monitoring circuit. The contactsat the solar modules are to be implemented as NC contacts, and connected to form asignal chain.

Information

The signal chain may not exceed a loop resistance of 300 Ohms so as toprevent alarm contact 2 from being overloaded.



In combination with overnight shutdown, the anti-theft protection can be performed dayand night. Upon interruption of the signal chain, an anti-theft warning appears in theSCC display, and an e-mail message is sent immediately.Under "Device Set-up SMUs Parameters", the anti-theft protection can beactivated and deactivated. By default, the anti-theft protection is deactivated (set to"off").

The anti-theft protection can also be set directly in Sunny Data Control via the SCCparameters.

[ Parameters]

Overnight

shutdown

....on

Anti-theft

protection

.....off

SMA Technologie AG Values of the String Current Monitoring System


11 Values of the String Current Monitoring System

11.1 Groups' Mean ValuesAt the SCC, activate the submenu "SMUs" from the menu "Device Set-up". In the"Measured Values" submenu, the mean values of the measuring channels aredisplayed for each group, and updated at 5 minute intervals.

"Device Set-up...SMUs...Measured Values"

The mean values of the individual groups can also be read out in Sunny Data Control(see figure below).

[SMU Meas. Val. ]

mean value grp1

........300 mA

mean value grp2Š

.........290 mA

Values of the String Current Monitoring System SMA Technologie AG


11.2 Measured Values of the Measuring Channels"Device Set-up...SMUs...Devices...Measured Values"

Under this menu path, the currents of the individual measuring channels of theconnected SMUs are displayed, and updated at 5 minute intervals.

"Device Set-up...SMUs...Devices...Measured Values"

The measured values of the individual strings can also be read in the SDC Spot Valuesscreen.

[Measured Values]

I Channel 1

........2.35A

I Channel 2

........2.29A

SMA Technologie AG Warnings


12 WarningsThe warnings currently present, and the warnings history, can be displayed via themenu item "Failure".

"Device Set-up...SMUs...Failure"

The individual meanings of the warnings and failures in the SCC can be found in theSunny Central user manual.Warnings generated during the day are automatically reset at midnight. Like thewarnings, the individual error sums of the measuring channels are also reset at this time.

12.1 Active WarningsWarnings present at the SSM-C are displayed here. In addition, it is possible to confirmthe warning in the SC, and thus to reset the error sum.

"Device Set-up...SMUs...Failure"

12.2 Warnings HistoryAll past failures are listed here according to date of occurrence.

"Device Set-up...SMUs...Failure...Hist. Failures"

[ SMU Failures]

actual Failures

Hist. Failures

[ Actual Faults]

SMU Error quit

...quit

no faults

[Fault-History ]

no faults

Troubleshooting SMA Technologie AG


13 Troubleshooting

13.1 Problems when Detecting the SSMsThere are different reasons for problems arising when detecting the SMU boards in theSSM-C. Thus, conduct the following checks:• Check the cabling between SC and SSM-C, as well as between the individual

SSM-Cs.• Check the +55 V power supply at the connection area of the respective SSM-C.• Check the LEDs on the SMU board in the SSM-C.

Danger to life

For work to be carried out within the SSM-C, this device must be disconnected(see safety instructions in section 3.13).

1 2 3 4 5 6

Z9-X

9

L+

L+

Z2-X

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L-

L-

L-

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L+

12

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8

L-

12

Z1-X

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

L+

FA

2064706

0002374

Vers

.: A1

48

5H

CV

BP

-0

1

11

31

11

/07

FA20646760068725Vers.:C2

2903

06/0

7

Vers

.:A

1S

/N1728

SM

U8

HV

-DV

PB

Ms60-DC8FS

FA

2064706

0002374

Vers

.: A1

48

5H

CV

BP

-0

1

11

31

11

/07

FA20646760068725Vers.:C2

2903

06/0

7

Vers

.:A

1S

/N1728

SM

U8

HV

-DV

PB

Ms60-DC8FS

1 2 3 4

SMA Technologie AG Troubleshooting


• Is the SMU board equipped with the RS485 Piggy-Back?• Check the termination in the last SSM-C. The jumper must be mounted on one SMU

board (see section 7.4.4 "SSM-C Termination", page 29).• Check that the other SMU boards' jumpers are not mounted in the individual SSM-

Cs.• Is the bridge (7 - 9) fitted on the side of the SCC?• Is COM1 at the SCC equipped with an RS485 Piggy-Back?• Is COM1 configured correctly in the SCC?

LED 1 (green)Overvoltage protector

Glows: overvoltage protector 1 ok

LED 2 (green)Digital input (optional anti-theft protection)

Glows: digital input / anti-theft protection ok

LED 3 (orange)Data transfer

Glows: data transfer active

LED 4 (red)Board fault

Glows: fault on the string current monitoring system'scontrol board

Contact SMA Technologie AG


14 ContactSunny Central on the Internet at: www.SMA.de

You will find the following information at this site:

• Latest information on the Sunny Central and the SSM-C• The latest version of the design tool for calculation of cable lengths• Also, the latest version of Sunny Data Control for download

Address: SMA Technologie AGHannoversche Strasse 1-534266 NiestetalGERMANY

Telephone: +49 5 61 95 22 - 0 (central office)+49 5 61 95 22 - 299 (Sunny Central Serviceline)

Fax: +49 5 61 95 22 - 100 (central office)+49 5 61 95 22 - 359 (Sunny Central Serviceline)

E-mail: [email protected]@SMA.de

Internet: www.SMA.de

Legal Restrictions SMA Technologie AG

4 SSMC-TEN072310 Technical description

The information contained in this document is the property of SMA Technologie AG. Publishing its content,either partially or in full, requires the written permision of SMA Technologie AG. Any internal company copyingof the document for the purposes of evaluating the product or its correct implementation is allowed and doesnot require permission.

Exclusion of liabilityThe general terms and conditions of delivery of SMA Technologie AG shall apply.The content of these documents is continually checked and amended, where necessary. However,discrepancies cannot be excluded. No guarantee is made for the completeness of these documents. The latestversion is available on the Internet at www.SMA.de or from the usual sales channels.Guarantee or liability claims for damages of any kind are exlcuded if they are caused by one or more of thefollowing:• Improper or inappropriate use of the product• Operating the product in an unintended environment• Operating the product whilst ignoring relevant, statutory safety regulations in the deployment location• Ignoring safety warnings and instructions contained in all documents relevant to the product• Operating the product under incorrect safety or protection conditions• Altering the product or supplied software without authority• The product malfunctions due to operating attached or neighboring devices beyond statutory limit values• In case of unforeseen calamity or force majeure

Software licensingThe use of supplied software produced by SMA Technologie AG is subject to the following conditions:This software may be copied for internal company purposes and may be installed on any number ofcomputers. Supplied source codes may be changed or adapted for internal company purposes on your ownresponsibility. Drivers may also be transferred to other operating systems. Source codes may only be publishedwith the written permission of SMA Technologie AG. Sub-licensing of software is not permissible.Limitation of liability: SMA Technologie AG rejects any liability for direct or indirect damages arising from theuse of software developed by SMA Technologie AG. This also applies to the provision or non-provision ofsupport activities.Supplied software not developed by SMA Technologie AG is subject to the respective licensing and liabilityagreements of the manufacturer.

TrademarksAll trademarks are recognized even if these are not marked separately. Missing designations do not mean thata product or brand is not a registered trademark. SMA Technologie AGHannoversche Straße 1-534266 NiestetalGermanyTel. +49 561 9522-0Fax +49 561 9522-100www.SMA.deE-mail: [email protected]© 2005 SMA Technologie AG. All rights reserved.

www.SMA.deSales Solar Technology

SMA Technologie AGHannoversche Strasse 1–534266 Niestetal, GermanyTel. : +49 561 9522 4000Fax: +49 561 9522 4040E-Mail: [email protected]: +800 SUNNYBOYFreecall: +800 78669269

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