EM300S12AC277 300W 277V Outdoor Magnetic 12VAC Transformer

EM300S12AC277 300W 277V Outdoor Magnetic 12VAC Transformer

The EM300S12AC277 is a 300W outdoor magnetic AC transformer / LED driver configured for 277V commercial input and a single 12VAC output circuit. Its encapsulated transformer and black powder-coated NEMA 3R steel enclosure make it suited to compatible professional lighting installations that use 277V supply power.

Why Choose the EM300S12AC277?

✔ 277V Commercial Input
Designed for 277V 60Hz input applications where standard 120V transformers are not appropriate.

✔ 300W 12VAC Output
Provides up to 300W of single-circuit 12VAC low voltage power.

✔ Outdoor NEMA 3R Enclosure
Black powder-coated steel enclosure protects the encapsulated magnetic transformer.

✔ Certified Construction
Conforms to UL 2108 and is certified to CSA C22.2 No. 250.0.

Electrical Specifications

• Input Voltage: 277V 60Hz
• Max. Input Current: 2.8A at full load
• Output Voltage - No Load: 12.7VAC
• Output Voltage - Fully Loaded: 11.5VAC
• Max. Total Wattage: 300W
• Max. Output Current: 25A
• Efficiency: 93%

Construction & Certification

• Enclosure: Black powder-coated steel, outdoor NEMA 3R
• Transformer Construction: Encapsulated magnetic transformer with separated primary and secondary windings
• Certification: Conforms to UL 2108; certified to CSA C22.2 No. 250.0
• Secondary Breaker: 25A manually reset
• Dimensions: 8 × 4.1 × 3.24 in

How to Select the 300W 277V 12VAC outdoor magnetic transformer

Choose the EM300S12AC277 when a project requires a 300W 277V 12VAC outdoor magnetic transformer and the available supply matches 277V 60Hz. Confirm that every connected fixture accepts 12VAC and that the planned load fits the transformer’s circuit configuration. Its black powder-coated NEMA 3R steel enclosure is intended for outdoor transformer installations.

This is a single-circuit model, so all connected fixture wattage counts toward the listed 300W maximum. The specifications show 12.7VAC at no load and 11.5VAC at full load, giving installers a reference for expected output as the connected load changes. Final transformer location, wiring, circuit protection and code compliance should be reviewed by a qualified installer before the system is energized.

Frequently Asked Questions

What lighting systems can use the EM300S12AC277?
This 300W 277V 12VAC outdoor magnetic transformer is intended for compatible low-voltage landscape or architectural lighting that accepts 12VAC power. The connected load must stay within the listed 300W capacity and 25A output-current limit.

Is the EM300S12AC277 dimmable?
Dimming is not listed as a feature in the supplied product data. Confirm dimmer compatibility in the EMCOD specification sheet before designing a dimming system.

Can this transformer be installed outdoors?
Yes. Its black powder-coated NEMA 3R steel enclosure is specified for outdoor transformer installations. Final placement and wiring must still follow the product instructions and applicable electrical requirements.

Compare voltage, capacity, circuit and enclosure options in our low-voltage landscape lighting transformer collection.

Official EMCOD Specification Sheet: Download PDF