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Sine Wave Inverter
300 watts continuous, 600 Watts surge (10 minutes)
12Vdc to 115Vac


The SureSine inverter has been developed using Morningstar's power electronics expertise and 25 years of experience with remote off-grid photovoltaic (PV) systems. This product is a pure sine wave inverter designed specifically to meet the needs of rural PV electrification requiring AC power including solar home systems, schools, community centers and health clinics. This inverter is also a good choice for small PV systems for telecom, remote cabins and weekend homes, and RV/caravans and boats.

The SureSine's combination of performance, features and competitive price provides the best small inverter value on the market. It is highly reliable, having no internal cooling fan or other moving parts prone to failure.

Features of the Morningstar SI-300-115V SureSine 300W Inverter, 115V, 60Hz:

* Pure Sine Wave
* Handles up to 200% surge
* 55mA self consumption (standby mode)
* No internal cooling fan
* Adjustable and Programmable
* Toroidal transformer design
* Peak efficiency of 92%
* Extensive electronic protections with automatic recovery
* Protected against harsh tropical and marine environment

Key Features and Benefits of the Morningstar SI-300-115V SureSine 300W Inverter, 115V, 60Hz:

Load Operation

Pure Sine Wave Provides quality AC equivalent to grid power. A sine wave will extend the life of the household appliances (lights, TV, fans) and improve load performance. Toroidal transformer design Generates good wave form throughout the range of input voltages.

Outstanding Surge Capability Handles a 200% surge during load start-up, to a maximum of 600 watts.

Power Available

High Efficiency A high peak efficiency will reduce heating and make more solar energy available for powering loads.

Low Self-Consumption The SureSine consumes 450mA while powering loads. During no load conditions, solar energy is not wasted because the SureSine automatically powers down to stand-by mode, reducing self-consumption to one tenth of operating consumption.

High Reliability

Extensive Electronic Protections The SureSine has extensive electronic protections that will automatically protect against faults and user mistakes such as short circuit, overload, high temperature and low voltage disconnect. Recovery from most faults is automatic.

No Internal Cooling Fan A key design objective since fans often fail in harsh environments and are noisy, consume power and blow dirt into the electronics.

Tropicalization The SureSine uses epoxy encapsulation, conformal coating, stainless steel hardware, and an anodized aluminum enclosure to protect against harsh tropical and marine environments.

Other Features

More Information The two LEDs provide important information to the user about system status and any fault conditions. An optional digital meter may be connected to the SureSine to display additional system information.

Remote On/Off Improves safety by making it easy to install the SureSine in an inaccessible location or enclosure. Reduces system cost by avoiding the need to add an AC safety disconnect to the system.

Adjustability Four DIP switches provide easy adjustability of several system parameters. Additional adjustability is possible via RJ-11 to RS-232 adapter to a personal computer and using Morningstar's PC software

For the advantages of sine wave inverters click here.



Continuous Power Output 300 watts
Surge Rating 600 watts for 10 minutes
DC Input Voltage 12VDC (10.0-15.5Vdc)
AC Output Voltage 115Vac +10%
Output Frequency 60Hz +0.1%
Total harmonic distortion (THD) <4%
Peak Efficiency 92%
Self Consumption 450mA inverter ON at no-load
 25mA inverter OFF
 55mA standby
Output Wave Form Pure Sine Wave
Dimensions 8.4" x 4.0" x 6.1"


This inverter must be powered from a negative ground electrical system.   All passenger vehicles manufactured in the U.S.A. after 1955, and in Europe and Asia after 1971 have negative ground systems and are acceptable.



Item Number: SI-300-115V-UL
Price: $292
Price last updated 11/4/2014
Shipping Weight: 10 lbs.
This item normally ships in approximately 1 week or less.


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