White Papers and Documents

  • Retrofitting Backup Power to a String Inverter System

    The vast majority of grid tie PV systems are useless when grid failures occur. They shut down at the very time that the electricity generated on site is most needed. This does not need to be the case. There are a number of ways to ensure that a PV array does not become stranded during utility outages, the common thread between them all is that they utilize energy storage, additional inverters and a variety of different power electronics depending on the system design.
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  • Advantages of Morningstar’s DC Coupling vs AC Coupling

    Providing a simple, cost-effective battery backup PV solution has eluded solar PV manufacturers and installers for years. Even for the most simple split-phase Grid-Tied (G-T) battery backup PV system it is hard to make it cost effective and the cost of batteries is only part of the problem. The challenge is how to effectively extract energy from the PV system to charge the batteries during an outage without losing the G-T inverter efficiency to backfeed energy to the grid. Morningstar has developed a 600VDC Direct Charge Controller Transfer System whichwill provide G-T solar PV customers with more cost effective options than have been available before.
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  • Parallel Charging Using Multiple Controllers With Separate PV Arrays

    Large off-grid and battery backup PV systems, often require greater charging than a single controller can provide. To meet the charging requirements of these large systems, several TriStar™ or TriStar MPPT™ controllers can be connected in parallel to a battery bank. Each controller is connected to its own separate PV array. This document provides answers to frequently asked questions, and tips concerning the operation and setup of these large multiple TriStar and TriStar MPPT controller systems.
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  • Morningstar’s TrakStar™ MPPT Technology & Maximum Input Power

    With so many module manufacturers in the market, an extensively broad range of module choices are available to meet the needs of many different global markets. Morningstar’s MPPT controllers have a very wide voltage input range with which they can make use of these many modules for charging batteries in the off-grid market. However, finding the best fit and knowing how to correctly size them is sometimes challenging. This document discusses solar module sizing, and power ratings, and answers some of the more frequently asked questions in order to help make sense of the many options available on the market.
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  • Traditional PWM vs Morningstar’s TrakStar™ MPPT Technology

    Morningstar’s MPPT charge controllers use the TrakStar advanced control MPPT algorithm to harvest maximum power from a Solar Array’s peak power point. It is generally accepted that even the most basic MPPT controller will provide an additional 10‐15% of charging capability, when compared to a standard PWM regulator. Besides this extra charge capability, there are several other important differences and advantages between PWM & MPPT technologies—these basic differences & advantages are outlined in this whitepaper.
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  • Heat Dissipation of the TriStar & TriStar MPPT Controllers inside Enclosures

    This paper shows how to calculate the heat dissipation for Morningstar’s TriStar (PWM) and TriStar MPPT controllers, determine the air temperature rise inside an enclosure, and then determine the resulting heat sink temperature of the controller to ensure it is below its operating limits. There are also recommendations for how to reduce operating temperatures. With this information, system designers can make good decisions regarding thermal management and system design when installing Morningstar controllers inside enclosures.
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  • Morningstar Communications Document (Morningstar Product Connectivity Manual – Networking & Communications)

    A comprehensive guide to communication with Morningstar products including MeterBus networks, Serial RS-232 and EIA-485 networks, Ethernet, HTTP, web interfaces, related hardware and cables.
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  • Adjusting Morningstar Data Log File for Your Time Zone

    When retrieving Internal Log Data from a controller or creating a Data Log file with the data logging feature of MSView, the data gets saved to a .csv file which can be opened using a spreadsheet software program like Excel. The format of the Date and Time is in ISO 8601 format which is an international convention for exchanging date and time information.
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