About this instruction manual This instruction manual contains a description of the SolarMax MT series string inverters. It furthermore tells you how to install, commission, and operate the inverters. Familiarise yourself with the inverter functions and characteristics before you begin the installation work.
Safety instructions The MT series solar inverters have been designed and tested according to the latest tech- nological advances and the currently valid product safety standards. However, ignoring the safety instructions contained in this instruction manual may endanger the user, a third party, or property.
Symbols on the inverter Symbol Description Protective conductor connection DC disconnector Q1 position OFF - In this position the DC discon- nector Q1 is off (open) DC disconnector Q1 position ON - In this position the DC disconnec- tor Q1 is on (closed) Risk of death through high voltages! Only qualified electricians may perform work on the inverter.
Description The SolarMax MT series string inverters convert the direct current (DC) of a photovoltaic generator into grid-compliant alternating current (AC). In this, the current is inverted by a two-phase, transformerless circuit type. The connection and synchronous feed of the inverted current into the public power grid are permanently three-phase.
Views of the unit Front view Graphics display with status LED and three buttons Side view left Fan cover (air intake) Name plate DC disconnector Q1 Connection option for external protective conductor Side view right Fan cover (air outlet)
Block circuit diagram AC output AC measurement Ethernet / RS485 RS485 Status signalling contact Monitoring external input Inverter control Booster control DC input DC input DC input Tracker 1 Tracker 2 Tracker 3 *...
The installation substrate must have sufficient structural strength. ■ ■ CAUTION The casing of the SolarMax MT series inverter complies with protection class ■ ■ IP65. Thus, it can be installed outdoors, but the stated IP protection is only ensured if the included AC connector, an appropriate DC connector (MultiContact series 4) and the recommended RJ45 communications connectors are used.
CAUTION The inverter must be installed in a location protected from rain and snow. ■ ■ When installing several inverters next to each other, you must observe a distance ■ ■ of 0.5 metres between the inverters. This distance prevents the mutual thermal influence due to the hot exhaust air of the ventilation systems.
Scope of delivery Inverter ■ ■ AC connector ■ ■ Installation plate for wall installation ■ ■ Instruction manual and quick guide ■ ■ Accessory kit (installation material for wall installation and earth connection) ■ ■ Installation The inverter can be installed easily using the included installation plate and installation material on a level installation base.
Installation plate [mm] For the other measurements see Section 3.2. Holes for padlock (against theft) Recesses for lock with splint Electrical connection The MT series inverters have the following connection options:...
461 Integrated overvoltage protection The MT series inverters have integrated surge arresters (varistors) on both the DC and AC ends. On the DC end, each MPP tracker has a surge arrester from the plus and minus pole ■...
462 AC connection CAUTION The MT series inverters must be connected to a mains connection point meeting ■ ■ at least the requirements of overvoltage category 3. Mains fuses and cable cross-sections The following table contains information about the recommended mains fuses and the...
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The AC connector must be connected using a flexible cable as described in ■ ■ EN 60309-2/VDE 0623. The permissible cable diameter is 11 to 20mm. ■ ■ Cable strands with a maximum cross-section of 6mm² can be connected. ■ ■ Procedure 1.
463 DC connection The inverters are quipped with 2 (SolarMax 6MT2 / 8MT2 /10MT2 / 13MT2 / 15MT2) resp. 3 (SolarMax 13MT3 / 15MT3) MPP trackers. Each tracker has two plus and minus poles for the connection of two strings per tracker input. A string can be connected at tracker 2 of each of the inverters SM6MT2 and SM8MT2.
Only use MC4 connectors by MultiContact or connectors compatible with these ■ ■ for the connection of the DC supply lines. Due to the transformerless circuit type of the MT series inverters, the plus or ■ ■ minus pole of the PV generator must not be earthed under any circumstances.
Section 4.6. A suitable M12 mating connector to connect to the status signalling contact can be ordered from the SolarMax Service Centre. Remote retrieval of the operating status can be configured, see Section 6.8.2. Connecting conditions 250V / 30V ■ ■...
Not used Neutral conductor N 466 Communications sockets The SolarMax MT series inverters have two RJ45 sockets for data communication within a MaxComm network: The left-hand RJ45 socket is only an RS485 interface. The RS485 interface is used ■ ■...
468 External residual-current device (RCD) The SolarMax MT series inverters have an integrated AC/DC sensitive fault current sensor. This sensor is able to distinguish between the operational capacitive stray cur- rents (caused by capacities of the PV modules to the earth) and fault currents (caused by touching a pole of the PV generator).
Commissioning Switching on and off All SolarMax inverters work completely automatically. When the PV generator supplies enough power, the inverter switches on and then starts mains feed operation. At night, or when the DC end is shut down, the inverter is disconnected from the grid. Operating the inverter and the ability to communicate via the interfaces are only possible when the inverter is switched on.
■ ■ time. Thoroughly read the manual before starting initial start-up. Contact your grid ope- ■ ■ rator or the SolarMax Service Centre if you have any doubt regarding the settings you must select. 522 Procedure 1. Switch on the inverter as described in section 5.1.1. The “Initial setup” menu will be displayed: 2.
4. Select the correct country setting. – Press to confirm your entry. – Depending on the country setting selected, additional menus may be displayed (see Section 5.2.3). – The “Monit. ext. input” menu is then displayed. 5. If appropriate, activate the function: Menu Setting Description...
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Country setting “Denmark” Menu Setting Description ≤ 13.8 kVA Plant type The maximum plant system rating is 13.8 kVA. > 13.8 kVA – ≤ 30 kVA The plant system rating is higher than 13.8 kVA and/or does not exceed 30 kVA. >...
Menu Setting Description Guida Connessioni Required setting if the inverter is commissioned Standard* within a PV plant connected to the grid before 1 July 2012. CEI 0-21 Required setting if the inverter is commissioned within a PV plant connected to the grid after 30 June 2012.
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1023 since this range is reserved for predefined applications (referred to as “well known services”). NOTE You will find more details about data communication in the technical information “MaxComm network”. This document can be downloaded from our web- site at: www.solarmax.com/en/downloads/data-communication/maxcomm/.
Operation Graphics display The graphics display on the front of the inverter shows the inverter’s system variables, status information, and failure messages. The display allows you to learn the current device status, access the integrated data logger, and enter various settings for the inverter.
Overview If none of the three buttons is pushed for 120 seconds, the display returns automatically to the Overview menu showing the three most important values as well as the current operating status. Main menu The Main menu provides access to other menu levels. Use the arrow keys select the desired menu.
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NOTE The inverter measured values are not suitable for billing purposes or calculating effi- ciency. The measuring error may amount to up to ±5% depending on the measured value. Only the measured values of a calibrated electricity meter are decisive for billing purposes.
Statistics In the Statistics menu you can access the inverter’s internal data logger. The accessible statistics are for the most recent 31 days, 12 months or 10 years. The “Total” sub-menu contains the accumulated yield and operating data since initial start-up of the inverter. Use the button to highlight a statistic category.
662 Monthly statistics This menu provides access to the data from the most recent 12 months. Use the buttons to select a monthly statistic. Press the left button return to the Statistics menu. 663 Yearly statistics This menu provides access to the data from the most recent 10 years. Use the buttons to select a yearly statistic.
MaxTalk 2 Pro” instruction manual can be found on our website www.solarmax.com (Downloads area). You can request MaxTalk 2 Pro from the SolarMax Service Centre. The contact details can be found overleaf. Function / Parameter Description Unit...
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Function / Parameter Description Unit t Vac max 1 Release time for maximum admissible mains voltage Vac min 2 Minimum admissible mains voltage (second limit) t Vac min 2 Release time for minimum admissible mains voltage Vac max 2 Maximum admissible mains voltage (second limit) t Vac max 2 Release time for maximum admissible mains voltage Vac 10 min max...
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Function / Parameter Description Unit - f MC max Maximum admissible mains frequency - f MC min Minimum admissible mains frequency - t MC Monitoring Duration of the mains check P(f)-Mode Frequency-dependent power reduction Inactive/ - f start Starting frequency - f stop Stop frequency - P(f) MC f max...
Function / Parameter Description Unit - Vac Lock-In Low Lower value at which the reactive power mode "Q(Vac) mode 2" is activated. - QR 2 Fixed reactive power in reactive power mode "Q(Vac) mode 2" (when grid voltage is too low; in % of Pac nom) - Pac Lock Active power-dependent on/off switch for the reactive...
681 Implementing the settings Use the button to select a parameter. Press the button to select a highlighted parameter and switch into the editing mode to change it. In the editing mode each individual number is changed. Example: Using the button, the highlighted number can be increased.
Information This menu contains the following information: Device type ■ ■ Serial number ■ ■ Firmware version ■ ■ Status message and two-digit number code (if a device error occurs) ■ ■ Warning (alternating display if several warnings are active at the same time) ■...
6102 Procedure Maximum voltage The set voltage monitoring threshold Vac max is displayed. ■ ■ The threshold value is decremented linearly until it reaches the current mains voltage ■ ■ value and grid monitoring is triggered. The trigger value, the trigger time, the current value, and the default value of voltage ■...
Operating status Status messages and status LED The status message in the graphics display describes the current operating status of the inverter. Each inverter status message belongs to one of the five possible operating sta- tuses. The status LED always displays one of these operating statuses through a variety of colours.
Mains operation Status message Description Mains operation The inverter has been switched to the grid and is feeding power into the grid. Maximum power The inverter limits the output power to the maximum permissible level. Limiting the power can occur when the PV generator has been oversized or in the event of high irradiation.
■ ■ Information about the failure you are experiencing (status message, etc.) ■ ■ Availability The contact details of the SolarMax Service Center can be found on the back of this instruction manual. SolarMax Produktions GmbH Zur Schönhalde 10 D-89352 Ellzee...
Diagnosis & measures The following tables describe possible measures for remedying failures. If the mea- sures suggested do not correct the failure, please contact the SolarMax Service Centre immediately. 821 General troubleshooting Cause Steps The display remains blank DC disconnector Q1 is Switch on DC disconnector switched off.
Cause Measure RTC error The RTC (real-time clock) in If this problem happens fre- the inverter is malfunctioning, quently, contact the SolarMax the date and time have been Service Centre. Set the time reset. and date correctly. Flash error A flash error has occurred.
Cause Measure Device error (+ error code) An internal error has occurred Check the two-digit error code in the inverter. displayed and contact the SolarMax Service Centre. 825 Blockings Status message Cause Measure External blocking There is a 0% command from None.
Maintenance SolarMax inverters are basically maintenance-free. However, in order to ensure perfect operation over the course of several years, in addition to regular controls of the operating and yield data via the inverter display or remote monitoring, we also recommend per- forming the simple maintenance work described below at regular intervals.
11 Technical data 6MT2 8MT2 10MT2 Input 340… 750 V 300… 750 V 290… 750 V MPP voltage range values Minimum DC voltage 250 V 250 V 250 V Maximum DC voltage 900 V 900 V 900 V Maximum DC current 1 x 9 A / 1 x 9 A 1 x 18 A / 1 x 9 A 2 x 18 A...
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1) for AC rated power output 2) max. 700 V with external power limitation 3) contact us if the installation location is at a higher level 4) certificates are not available for all models. Details can be found at www.solarmax.com 13MT2 15MT2 13MT3...
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1) for AC rated power output 2) max. 700 V with external power limitation 3) contact us if the installation location is at a higher level 4) certificates are not available for all models. Details can be found at www.solarmax.com...
SolarMax Productions GmbH (herafter SOLARMAX) guarantees the correct function and absence of defects of your SolarMax tools for a particular, device -specific duration of guarantee. This duration of guarantee can be prolonged by an extension of guarantee according to these Terms of Guarantee.
The services of the Basic Guarantee are only provided free of charge in countries released by SOLARMAX at the time of installation. Please clarify this with your dealer. You will find a current list of these countries in the appendix or on our homepage. On request we are happy to send you this list.
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Not covered by the guarantee are wear parts, especially fuses and overvoltage protection 5 Assertion of Guarantee For the assertion of the guarantee the SOLARMAX hotline must be contacted by phone or in written form and their instructions must be followed carefully.
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Therefore it is necessary to have a written confirmation by SOLARMAX, in order to restart the guarantee terms. 7 Guarantee Extension For devices with the Basic Guarantee BASIC the duration of guarantee can be prolonged by purchasing a guarantee extension within the following time periods. An extension for specific devices can be purchased on the basis of limited services.
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