PV String Monitoring Solution
Electronic Cards for use in PV Combiner Box Applications
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Mersen PV String Monitoring Solution
The goals of PV String Monitoring
– For the investor: to measure energy produced and forecasted revenues
– For the operator: to detect defects for maintenance
But most existing systems have huge limitations
• Precision is not good enough at inverter level
• Monitoring systems are proprietary
• Data interpretation is not easy
Need for high quality universal monitoring systems
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Pro-active maintenance
Optimized PV installation performance
Secured ROI, predictive revenues and reduced OPEX
Mersen PV String Monitoring Solution
The advantages of string level monitoring
– Detection of problems as soon as they appear
– Precise localization of problems in the PV installation
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Mersen PV String Monitoring Solution
Performance Ratio
Monitoring of operating conditions: T°, sun,…
Energy produced over time T
Energy expected over time TPerformance Ratio =
Monitoring of instantaneouselectrical parameters
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Mersen PV String Monitoring Solution
A precise control of the installation from the PV field to the inverter
Communication Gateway (GPRS, Ethernet, …)
String Monitoringin the combiner box
Monitoring Software
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Pyranomètre
Ens Modbus
Temp ext Modbus
Temp Cellule Modbus
Monitoring Software
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Mersen PV String Monitoring Solution
Product Offering– Flexible, High Performance Solution
– Three Electronic Cards• MAIN Card• AUX Card• PROBE Card
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Mersen PV String Monitoring Solution
Monitor 6 to 30 strings by connecting up to (4) AUX Cards to the MAIN Card
Monitor up to 8 external inputs (7 analog + 1 digital) by connecting the PROBE Card
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6 PV string inputs Max voltage: ± 1000 Vdc Max current: ± 25 A Precision: ± 0.5%
Autonomous power supply from PV strings 250Vdc to 1000Vdc string voltage Low power consumption: 4W @1000Vdc
Aux Card extension: up to 4 Aux. cards in parallel 6 strings monitored per card 6, 12, 18, 24 or 30 strings can be monitored by one single box
Probe Card extension: 1 digital sensor 7 analog sensors:
• 4-20mA, ±1% precision• 1-10V, ±1% precision
Communication: MODBUS on isolated RS485 (1.2km cable)
32bits microcontrollers Modbus Communication Measurement & data processing 16Mbit memory (6 months data storage worse case)
Diagnostic & control: 4 digital inputs 3 external relay control
Reliable operating range -40°C to +70°C operating temperature onboard temperature sensors (-40°C to +100°C ±2°C)
Integrated Bus Bar 150A combined output (two output terminals, 75A each)
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Mersen PV String Monitoring Solution
Features and Benefits– Built-in Power Supply – Take power directly from the PV string.
Eliminates the need to purchase and install a separate power supply to power the monitoring device
– Accuracy – 0.5% precision
– Voltage and Current Measurement – Additional voltage measurement provides a greater level of detail and is required by some integrators
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Mersen PV String Monitoring Solution
Features and Benefits– Flexible 6-String Device – Allows for greater flexibility (can be
configured for 6, 12, 18, 24 or 30 string boxes)
– Integrated Bus Bar – Combines strings into 1 or 2 outputs based on ampere rating. Eliminates the need for separate comb bus bar
– Increased Functionality – Option to connect up to 8 external sensors (anemometer, thermometer, sun sensor, etc…)
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Mersen PV String Monitoring Solution
Available Resources and Tools
ep-us.mersen.com
PowerPoint
Data Sheet
Installation Guide
Tech Topics
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ep-us.mersen.com
MAIN Card AUX CardPROBE Card