MK075KB 75 kVA Transformer, 480V to 208Y/120V 3-Phase, NEMA 3R by Hammond

MK075KB 75 kVA Transformer, 480V to 208Y/120V 3-Phase, NEMA 3R by Hammond

If you have 480V three-phase power coming into your building but need standard 208V and 120V circuits, this is the transformer that bridges the gap. The Hammond MK075KB is a 75 kVA three-phase unit that takes 480V on the input side and converts it to 208Y/120V on the output, which gives you both 208V for equipment and 120V for everyday outlets and lighting. A transformer like this is what makes a 480V industrial service usable for normal building loads.

It comes in a NEMA 3R housing, which simply means it is weather-rated and can be installed indoors or outdoors. The unit is self-cooling, so there is nothing to plug in or maintain beyond the wiring connections. If you are not certain this is the exact unit you need, the key details are below.

Common Applications

• Getting 208V and 120V circuits from a 480V three-phase power supply
• Powering lighting, outlets, and equipment in commercial and light industrial buildings
• Replacing an older transformer of the same 75 kVA rating
• Indoor or outdoor installations where a weather-rated unit is needed

Key Features

• 480V to 208Y/120V conversion: Turns a 480V three-phase feed into usable 208V and 120V power.
• 75 kVA capacity: Sized for general building and light industrial loads.
• Weather-rated enclosure: NEMA 3R housing works indoors or outdoors.
• No maintenance cooling: Cools itself with natural airflow, with no fans to service.
• Adjustable taps: Built-in voltage taps let an electrician fine-tune the output.
• Safety certified: UL Listed and CSA Certified for general distribution use.

Specifications

• Manufacturer: Hammond Power Solutions
• Catalog Number: MK075KB
• Power Rating: 75 kVA
• Phase: 3-Phase
• Frequency: 60 Hz
• Input (Primary) Voltage: 480V Delta
• Output (Secondary) Voltage: 208Y/120V
• Winding Material: Aluminum
• Temperature Rise: 150°C
• Insulation System: 220°C
• Cooling: Self-air-cooled (Class AA)
• Impedance: Approximately 5%
• Enclosure: NEMA 3R, grey finish
• Mounting: Floor mount
• Certifications: UL Listed, CSA Certified

Product Identification

• UPC/GTIN: 803423013905
• Dimensions (H x W x D): 38 in x 26 in x 21 in
• Weight: Approximately 575 lb

FAQ

What does the MK075KB do? It converts 480V three-phase power into 208Y/120V power, so you can run both 208V equipment and standard 120V outlets and lights from a 480V service.

How do I know if this is the right transformer for me? If your incoming power is 480V three-phase and you need 208V and 120V circuits at up to 75 kVA, this is the matching unit. If your input or output voltage is different, you will need a different model.

Can it be installed outside? Yes. The NEMA 3R enclosure is weather-rated for indoor or outdoor use.

Does it need any special power or cooling? No. It cools itself with natural airflow and has no fans or extra power requirements.

Who should install it? A licensed electrician. This is a heavy, high-voltage unit that must be wired and grounded to code.

Is there a newer version? Yes. The NMK075KB is the updated model that meets current DOE 2016 energy standards, with the same ratings.