CARLO GAVAZZI ISMG 315 User manual

User Manual
ISMG 315 / ISMG 320
Three-Phase Solar Inverter

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© 2010 Carlo Gavazzi Automation All rights reserved V 1.3 July 2010

Safety
KEE THESE INSTRUCTIONS FOR FUTURE REFERENCE – This manual contains
important instructions for Models ISMG 315 and ISMG 320 that shall be followed
during installation and future maintenance of the ISMG inverter.
Safety Precautions/Safety Notes
Only trained skilled and qualified electrical personnel shall carry out e electrical
installation, wiring, opening of the ISMG inverters. Even when no external voltage
is present, or the device is disconnected, the ISMG inverters can still store high
voltages and cause of electric shocks.
The temperature of the external heat sinks of the device can reach over 70°C
(158°F) in normal operation (Ambient temperature rating: 45°C / 113°F). There is
high risk of burn injury if these parts are touched.
The following general safety precautions must be observed during all operation
phases, service and installation of this device. Failure to comply with these safaty
precautions or specific warnings, elsewhere in this manual, violates safety
standards of design, manufacture, and intended use of the device. The
manufacturer assumes no liability for the customer’s failure to comply with these
requirements.

Safety Sy bols
To reduce the risk of injury and to ensure the continued safe operation of this
product, the safety related information, contained in this manual are marked with
the below listed signs.
Warning, risk of electric shock
These
safety infor ation prevent serious injuries or death to users
and/or installers.
Earth ground sy bol
!
Caution
These infor ation prevent da age to the product.
Intended Use
ISMG3 Series inverters shall be installed according to the specific norms and
regulations of your local building and safety department to meet the following
qualifications:
 Electrical installation must be carried out correctly to meet the applicable
regulations and standards;
 ISMG3 Series inverters shall be installed in a well ventilated environment and
protected against rain, condensation, moisture and dust;
 ISMG3 Series inverters shall be installed in a permanent location according to
the instructions stated in this manual;
 ISMG3 Series inverters shall operate according to the technical specifications
stated in this manual.

General Safety Precautions
 Remove all conductive jewelry or personal accessories prior to installation or
service of the device, parts, connectors, and/or wirings.
 Only trained and qualified personnel is authorised to mount, reconfigure or
repair this device.
 Only licensed electricians are entitled to install permanently wired
equipments.
 Make sure of standing on an insulated surface when working on the
operating device (i.e: avoid grounding of the person).
 Instructions and information on cautions contained in this manual must be
carefully read and followed.
 Use proper lifting techniques whenever handling enclosure, equipment or
parts.
 The ISMG3 inverter must be provided with an equipment-grounding
conductor connected according to local norms and regulations.
 The AC Neutral connection is only for voltage sensing and shall be neither
used to carry currents nor connected to ground inside the inverter.
 The list does not contain all measures pertinent to the safe operation of the
device. If special problems arise which are not described in sufficient detail
for the purposes of the buyer, contact your local Carlo Gavazzi National Sales
company or specialized dealer or technician.

Safe Installation and Operation
 Installation of the device must be in accordance with the relevant national or
local regulations. Correct grounding and short circuit protection must be
provided to ensure operational safety.
 Read all instructions and caution remarks in the manual before installation.
 Switch off the circuit breakers before installation and wirings. Avoid standing
on wet surfaces when working on the inverter.
 V arrays will be energized when exposed to light. Cover the arrays with
opaque (dark) material during installation and wiring. Always make sure the
DC switch is on the OFF position.
 Check both of the AC and DC connections with a digital volt meter prior to
any installation or removal procedures.
 Close the cover properly before switching on the circuit breakers.
 Not to install the inverter exposed to direct sunlight
 When no external voltage is present; the ISMG3 inverter can still contain high
voltages. There is still risk of electrical shocks.
 Allow at least 5 minutes for the inverter to discharge completely after
disconnecting the AC and DC sources from the inverter.
 External heat sinks can reach a relatively high temperature in normal
operation and cause skin burn injury if touched. ay attention to it.
 To prevent the risk of fire hazard, do not cover or obstruct the heat sink.
 Any modification to the electrical system shall be carried out only by qualified
electricians.

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Wiring the inverter
WARNING!
All electrical installation and the wiring ethods shall be done in
accordance with the relevant national or local electrical regulations
and should follow the i portant safety instructions in this anual.
WARNING!
Make sure that you use suitable connecting cables for both the AC
and DC wirings. The cables ust be adequately di ensioned and
suitably inert to te perature fluctuation, UV radiation and other
possible hazards.
WARNING!
Reconfir that all connections have been perfor ed properly and
all screws are properly tightened.
Connection of the DC cable
For DC Input Ter inals, use wire size 10 to 16 2 (#8 to #6 AWG), 90°C
(194°F) Copper Wire.
CAUTION!
Identify the different polarity of DC voltage on each PV string and
connect respectively to the input ter inals. Make sure the DC
voltage that PV arrays generate is equal or less than 850 VDC in any
case.
WARNING!
Route the DC connection cables to the ISMG3 inverters away fro
any possible hazards that could da age the cables.
WARNING!
Hazardous voltage is still present on the device after disconnection
of all PV DC inputs. Allow 5 inutes for the inverter to discharge
the energy co pletely.
WARNING!
PV arrays will be energized when exposed to light. Cover the arrays
with opaque aterials during installation and wiring.

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!
!
!
Connection of the AC cable
For AC Output Ter inals, use wire size 6 to 10 2 (#10 to #8 AWG), 90°C
(194°F) Copper Wire.
WARNING!
Make sure that the circuit breaker of utility ains is switched OFF
before connecting the power cables fro the breaker to the AC
connector.
Interaction with the Utility Grid
CAUTION!
The default interface protection has been verified according to the
valid low-voltage national grid connection standards. Only the
authorized installers can change the tripping-li it settings under
the approval of the distribution network operator (DNO).
CAUTION!
Confir the grid connection standard is selected correctly before
tied with the grid (Std. DK5940 for Italy, VDE0126-1-1 for Ger any
or RD1663 for Spain). Please refer to the Section 3.3.5 Setting
Operation for the selection of the grid connection standards.
CAUTION!
The default interface protection is saved per anently in the
EEPROM and won’t be erased even if the inverter shuts down.
Repair and Maintenance
The inverter contains no user serviceable parts inside, except for the fans.
Only CARLO GAVAZZI LOGISTICS SpA trained staff is authorized to repair the
unit. lease return the equipment for further examination if the faults are not
caused by fans.
WARNING!
Not to ake alterations or ta per asse bly in the inverter unless
expressly specified elsewhere in this Manual. Doing so ay result
in injury, electric shock, or fire and of corse void the warranty.

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Contents
1. INTRODUCTION 3
1.1 G ENERAL 3
1.2 S ECIFICATIONS 5
1.3 F EATURES 11
1.4 A CCESSORIES 11
2. INSTALLATION 12
2.1 LACEMENT 12
2.2 M OUNTING 14
2.3 W IRING THE INVERTER 20
2.3.1 Connection of the AC cable................................................................27
2.3.2 Connection of the DC cable ...............................................................29
2.3.3 Connection of the Communication cable .........................................32
2.4 W IRING INVERTER IN ARALLEL 35
3. OPERATION 36
3.1 O VERVIEW 36
3.2 O ERATION F EATURES 39
3.3 LCD D IS LAY 40
3.3.1 LCD Backlight Indication ....................................................................41
3.3.2 Display messages flow.......................................................................43
3.3.3 roduced ower Graphs.......................................................................52
3.3.4 Error Messages...................................................................................54
3.3.5 Setting Operation...............................................................................55
3.4 A UTO T EST (O NLY FOR ISMG315IT AND ISMGT320IT) 57
3.4.1 Auto test C Software ........................................................................58
3.4.2 Use Self-testing...................................................................................62

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3.5 E RROR M ESSAGES DESCRI TION 64
3.6 T ROUBLESHOOTING 68
4. TECHNICAL DOCUMENTATION 73
4.1 O UTLINE D RAWING 73
4.2 E FFICIENCY 74
4.3 D E - RATING O ERATION 75
4.4 M E FFICIENCY 78
5. WARRANTY INFORMATION 80

List of Figures
Fig1.1.1 Grid Connected Solar System Overview................................................... 4
Fig 2.1.1 Clearances required for ISMG3 inverter installation ..........................13
Fig 2.2.2 Inverter mounting bracket ...................................................................15
Fig 2.2.3 Fasten the mounting bracket ...............................................................16
Fig 2.2.4 Hook the Inverter on the mounting bracket and then fasten the screw
19
Fig 2.3.1 Turn the DC disconnect switch OFF......................................................20
Fig 2.3.2 Loosen the screws .................................................................................21
Fig 2.3.3 Open the front lid of the wiring box.....................................................22
Fig 2.3.4 Removal of the covers for the cable through holes ............................23
Fig 2.3.5 Wiring box front view ...........................................................................24
Fig 2.3.6 Utility Grid Configuration .....................................................................26
Fig 2.3.1.1 AC Terminal Block for AC cable connections ..................................27
Fig 2.3.2.1 ISMG3 Inverter supports two (2) independent V strings....................29
Fig 2.3.2.2 V Inverter Connections ..................................................................30
Fig 2.3.2.3 V Strings in arallel ........................................................................30
Fig 2.3.3.1 ositions of the communication ports and termination switch....32
Fig 2.3.3.2 RJ-45 ins and Signals......................................................................33
Fig 2.3.3.3 RS-232 connection (ISMG-45S0918) ...............................................34
Fig 2.3.3.4 RS-485 connection ...........................................................................34
Fig 3.3.1 Front panel of the ISMG3 inverter .......................................................40
Fig 3.3.1.1 3 colours LCD backlight....................................................................41
Fig 3.4.1.1 Search for inverters..........................................................................58
Fig 3.4.1.3 Auto-test process ..............................................................................61
Fig 4.1.1 Outline Drawing of ISMG3....................................................................73
Fig 4.2.1 Efficiency of the ISMG320 = 96.0% ......................................................74
Fig 4.2.2 Efficiency of the ISMG315 = 95.5% ......................................................74

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Fig 4.3.1 Temperature de-rating curve of the ISMG320....................................75
Fig 4.3.2 DC ower curve of the independent V string of the ISMG320.....76
Fig 4.3.3 Output ower v.s. Grid voltage of the ISMG320 ..................................77
Fig 4.4.1 M Efficiency of the two V strings in parallel .................................78
Fig 4.4.2 M Efficiency of the two V strings in individual..............................78

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1. Introduction
1.1 General
The Carlo Gavazzi ISMG3 product family is a series of grid-connected photovoltaic
inverters which are designed to convert DC power generated by photovoltaic
arrays to AC power that is delivered into the utility grid. The ISMG315 and
ISMG320 are devices of the family with three (3) phases AC outputs for the
European market. The overview of the grid-tied solar energy system is shown in
Fig 1.1.1. ISMG3 inverters utilize the state-of-the-art technology to achieve the
purpose of high reliability and ease of use. In addition, ISMG315 and ISMG320
comply with the requirements of VDE0126-1-1, RD1663/RD661 and DK5940
Standards. Furthermore the 3-phase ISMG3 inverters are certified to comply with
the Standard EN50178 and EN55022 EMC Regulations with Class A device.
The ISMG3 inverter is designed to operate automatically once it is installed and
commissioned correctly according to the technical specifications. When the DC
input voltage generated by the photovoltaic arrays raises above the minimum
M T voltage setting, the embedded controller starts and goes into the system
initialization mode. If the DC input voltage goes above the V Start voltage point,
the inverter will go into Checking mode (Riso check) and monitor all parameters
needed for grid connection. During this time, the ISMG3 inverter is not generating
AC power yet. Once all conditions necessary for grid connection are satisfied, the
ISMG3 inverter goes into the Grid/M mode and begins feeding the AC power
into the grid. When the input DC voltage falls below the pre-set threshold voltage
setting, the ISMG3 inverter will then shut off the output AC power. And the
inverter will shut down itself when the DC input voltage is under the minimum

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M T voltage setting. The ISMG3 inverter will be awakened again automatically
when the input DC voltage rises above the minimum M T voltage point.
We appreciated your choice of Carlo Gavazzi ISMG3 inverters for your power
conversion devices in your solar power system. This document contains the
information you need for the installation and settings of the ISMG3 inverters.
Therefore, it is strongly recommended to read this manual carefully before the
ISMG3 inverter installation and settings.
Fig1.1.1 Grid Connected Solar System Overview

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1.2 Specifications
Specifications for ISMG315 and ISMG320
Na e-Part nu ber ISMG 315 ISMG 320
Grid output (AC)
Grid voltage, nominal 400VAC 3 H/N/ E
Grid voltage, operating range 320 ~ 460VAC
Grid frequency, nominal 50 Hz
Grid frequency, operating
range
48~52.5 Hz (adjustable)*
Nominal Output ower 15,000 W 20,000 W (19,990W**)
Maximum output power 16,500 W 22,000 W
Nominal Output Current
21.8 A 29.0 A
Maximum Output Current
28.2 A 31.9 A (31.88A**)
Waveform True sine
ower factor > 0.99 @ nominal power
Total Harmonic Distortion < 5 %
DC Component < 0.5 %
hase Three hase
Solar input (DC)
Maximum DC ower
17,300 W 23,100 W
Maximum input voltage 850 VDC
Input voltage range 300 ~ 850 VDC
M voltage range 400 ~ 850 VDC
V start voltage 400 VDC (adjustable)
Nominal voltage 630 VDC
Nominal input current 2x19.7A (39.4 A) 2x26.3A (52.5 A)

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Maximum input current 2x21.6A (43.3 A) 2x28.9A (57.8 A)
General
Na e-Part nu ber ISMG 315 ISMG 320
Maximum efficiency 96.7 % 97.0 %
CEC efficiency 95.5 % 96.0 %
Night consumption < 1W
Environ ental
Operating temperature range -25° ~ +60°C (-13° ~ +140°F)
Storage temperature range -25° ~ +70°C (-13° ~ +158°F)
Maximum full power operating
ambient 50°C (122°F) 45°C (113°F)
Relative humidity Max. 95 %
Mechanical
Outdoor enclosure I 55, ref. IEC 60529(2001)
Cooling Intelligent control fan
Input & Output terminals
DC input - Accept wire size of 10 to 16 mm2
(#8 to #6 AWG)
AC output - Accept wire size of 6 to 10 mm2
(#10 to #8 AWG)
Weight/Shipping weight 75 kg / 85kg (165.3 lb / 187.3 lb )
Dimensions (HxWxD) 890.5×751×245.5 mm (35.1×29.6×9.7 inches)
Shipping dimensions (HxWxD) 1130×900×700 mm (44.6×35.5×27.6 inches)
Interface
Communication RS232 and RS485
Display 128 * 64 graphic display
Certifications
Electromagnet Compatibility
Directive 2004/108/EC
EN 55022(1998) : IEC/CIS R22
EN 61000-6-2(2005)
EN 61000-6-4(2007)
EN 61000-3-11(2000)

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EN 61000-3-12(2004)
Low-Voltage Regulation Directive 2006/95/EC
EN 50178(1997), covered by IEC 62103(2003)
Network Monitoring
VDE 0126-1-1(2006), RD 1663(2000) / RD 661
(2007), DK 5940(2007) / Enel Connections Guide
(2008), Section F
RoHS Directive 2002/95/EC
* Some factory settings can be re-
configured with the approval of the local utility
provider. This inverter is provided with adjustable
trip limits and may be
aggregated over 200kW on a single oint of Common Coupling.
** The output power capacity is limited to 19.99 kW
on the ISMG315IT and on the
ISMG320IT according to the DK5940 for the Italian market only.

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Adjustable voltage, Frequency and Reconnection Settings (1)
DK5940 VDE0126-1-1
Setting Range Default Range Default
Over-frequency (Hz) 50.05~50.95 50.25 50.05~50.15 50.15
Over-frequency
disconnection time (cycle) 1~3 3 1~8 8
Under-frequency (Hz) 49.05~49.95 49.75 47.55~49.95 47.55
Under-frequency
disconnection time (cycle) 1~4 4 1~8 8
Over-voltage (Vac) 235~270 270 235~260 260
Over-voltage
disconnection time (cycle) 1~4 4 1~8 8
Under-voltage (Vac) 188~225 188 188~225 188
Under-voltage
disconnection time (cycle) 1~8 8 1~8 8
Dc injection tripping
current (A) 0.10~0.60 0.60 0.10~0.80 0.80
Dc injection
disconnection time (cycle) 1~4 4 1~8 8
Insulation resistance trip
setting (MOhm) 0.5~10 1.0 0.5~10 1.0
V start voltage (Vdc) 400~800 400 400~800 400
Reconnect delay* (s) 20~300 20 30~300 30
* Once a grid failure occurred, the ISMG3 inverter waits 20~600 seconds before
the next connection to the grid. The default setting is 20 seconds for DK5940
(Italy), 30 seconds VDE0126 (Germany) and 180 seconds for RD1663 (Spain).

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Adjustable voltage, Frequency and Reconnection Settings (2)
RD1663 User
Setting Range Default Range Default
Over-frequency (Hz) 50.05~50.95 50.95 50.05~54.50 50.95
Over-frequency
disconnection time (cycle) 1~8 8 1~250 4
Under-frequency (Hz) 48.05~49.95 48.05 45.50~49.95 49.05
Under-frequency
disconnection time (cycle) 1~8 8 1~250 4
Over-voltage (Vac) 235~249 249 235~276 264
Over-voltage
disconnection time (cycle) 1~8 8 1~150 4
Under-voltage (Vac) 199~225 199 160~225 196
Under-voltage
disconnection time (cycle) 1~8 8 1~150 4
Dc injection tripping
current (A) 0.10~0.80 0.80 0.10~0.80 0.80
Dc injection
disconnection time (cycle) 1~150 8 1~150 8
Insulation resistance trip
setting (MOhm) 0.5~10 1.0 0.5~10 1.0
V start voltage (Vdc) 400~800 400 400~800 400
Reconnect delay* (s) 180~300 180 20~600 20
* Once a grid failure occurred, the ISMG3 inverter waits 20~600 seconds before
the next connection to the grid. The default setting is 20 seconds for DK5940
(Italy), 30 seconds VDE0126 (Germany) and 180 seconds for RD1663 (Spain).

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Measure ent precision
Resolution
Range
Display Measure ent
Accuracy
Input voltage (VDC) 0~900V 0.1V 0.3V ±2V
Input Current (IDC) 0~50000mA 100mA 15mA ±500mA
Grid voltage (VAC) 0~300V 0.1V 0.3V ±1V
Grid current (IAC) 0~60000mA 100mA 30mA ±500mA
Grid frequency (Hz) 45~65Hz 0.01Hz 0.001Hz ±0.02Hz
Output power (W) 0~22000W 1W 1W ±50W
Energy yield (kWh) 0~65535×103kWh 0.1kWh 2.2×10-6kWh 1%