Enphase Micro-Inverter M190-72-240-S11, MC3, MPPT
Maximum Output Power: 190 Watts
54VDC / 240VAC
For 60 and 72 cell solar modules
This inverter has MC3 connectors (Enphase calls them Type 1)
Enphase Energy presents the first commercially available Micro-Inverter
system for residential and commercial solar PV applications. The
Enphase Micro-Inverter system utilizes advanced technologies to
maximize energy harvest, increase system reliability and dramatically
simplify design, installation and management.
The
Enphase Micro-inverter shifts DC to AC conversion from a large,
centralized inverter to a compact unit attached directly to each solar
module in the power system. Distributing the conversion process to each
module makes the entire solar power system more productive, reliable,
and smarter than traditional inverter systems.
Productive- Maximum energy production
- Resilient to dust, debris, and shading
- Performance monitoring per module
Reliable
- MTBF of 331 years
- System availability greater than 99.8%
- No single point of failure
Smart- Quick & simple design, installation and management
- 24/7 monitoring and analysis
Solar Power Challenges
Solar power production is affected by various factors such as module mis-match, obstruction shading, inter-row shading, and obstacles such as dust or debris. In addition, non-uniform changes in temperature, irradiance, and shading create complex current-voltage curves, further affecting energy harvest. This is due to the fact that in traditional systems the performance of the entire system is dictated by the performance of the weakest module.
The Enphase Solution
The Enphase Energy Micro-inverter System solves solar power challenges by performing Maximum Power Point Tracking (MPPT) at each solar module. MPPT is an algorithm used to calculate and respond to temperature and light changes detected on a solar power system, and to determine how much power to draw from the module. In contrast, centralized inverter’s MPPT algorithm sees the entire solar power system as a single module, and responds to the lowest production numbers it detects.
Increased Productivity
The Enphase MPPT algorithm works at each solar module in an installation and achieves greater than 99.6% accuracy which enables it to maximize energy harvest at all times, even during variable light conditions. Tests show systems using Enphase Micro-inverters increase energy harvest by as much as 25% over systems using traditional inverters.
More Reliable
Traditional centralized inverters implementations create a single point of failure for solar power systems. If the inverter fails, the entire system is disabled. Enphase Micro-inverters convert power independently at each solar module. If one micro-inverter fails, the rest continue to operate as usual. Also, if a micro-inverter is damaged or fails, it can be replaced during routine maintenance or when convenient, further reducing maintenance costs.
Reduced Operational Costs
With the Enphase Micro-inverter System, installers are no longer limited by string design, marginal designs, co-planarity, and matched modules. The space, heat, and noise associated with a large inverter are eliminated. Enphase Micro-inverter Systems improve mechanical integration, reduce wiring time, and remove the need for DC switching points.
Flexibility
Another benefit of the distributed Micro-inverter design is the potential for installations to be expanded over time. An initial set of solar modules can be installed and additional modules added as needs and budgets grow without requiring the replacement of a large centralized inverter.
January 29, 2008
Technical Note
DC Disconnecting Means for Enphase Micro-Inverters The Enphase Micro-Inverter is a new inverter technology where each inverter individually connects to one individual PV module. This unique configuration insures that the maximum power available from each PV module is exported to the utility grid regardless of how the rest of the PV modules in the array are affected by shading, soiling, orientation, module mismatch, etc. The result is maximum energy production from the overall PV system. The Micro-Inverter also makes PV inherently safer than conventional string inverters. DC wire runs are minimized. Low voltage DC wires connect from the PV module directly to the co-located Micro-Inverter, eliminating the risk of personnel exposure to lethal 600Vdc power. The maximum DC voltage on the roof of any PV installation is now limited to the maximum voltage of any single PV panel (typically less than 50Vdc).
The DC disconnect requirements contained in NEC Article 690 are clearly intended for multiple module (array) arrangements. Section 690.13 states that you must provide a means “to disconnect all current-carrying conductors of a photovoltaic power source from all other conductors in a building . . .” By the very nature of the Micro-Inverter, there is no mixing of DC source circuit wiring with the building wiring.
By definition per 690.2; “Photovoltaic power source. An array or aggregate of arrays . . .”
By definition per 690.2; “Array. A mechanically integrated assembly of modules . . .”
The Enphase Micro-Inverter connecting to a single module, is clearly not a traditional “string” inverter, and is closer in concept to the AC module as defined in 690.2. Specific provisions are made for AC modules in 690.6. Here it is stated that, “The requirements of Article 690 pertaining to photovoltaic source circuits shall not apply to AC modules.”
In addition, the dialog and explanation in 690.14(B) clearly states that, “There is no intent or requirement to have a disconnecting means located in each PV source circuit or located physically at each PV module”.
Any requirement for DC disconnection is to aid in servicing. As such, 690.18 makes provision for “opaque covering” to disable the array or portions of the array. Finally, 690.33 allows the use of connectors to disconnect the DC. While it is uncertain that a DC disconnect is required by the NEC for a Micro-Inverter, clearly the PV module connectors will suffice as a means of disconnecting the PV module from the Micro-Inverter.
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