250-250-250-250-3/0 ALUMINUM SER CABLE

Allowable Ampacity for 250-250-250-250-3/0 ALUMINUM SER CABLE at 60°C: 170 Amps

Allowable Ampacity for 250-250-250-250-3/0 ALUMINUM SER CABLE at 75°C: 205 Amps

Allowable Ampacity for 250-250-250-250-3/0 ALUMINUM SER CABLE at 90°C: 230 Amps

Also Known As:

250-250-250-250-3/0 type r cable, 250-250-250-250-3/0 service entrance cable, 250-250-250-250-3/0 ser cable, 250-250-250-250-3/0 aluminum ser cable, 250-250-250-250-3/0 aluminum service entrance cable, 250-250-250-250-3/0 electrical entrance cable.

Applications:

Aluminum SER (Service Entrance) cable is primarily used for branch circuits and panel feeders in residential, commercial, and industrial settings. The voltage rating of this cable is 600 volts, and it is suitable for use in wet and dry locations, with an operating temperature up to 90°C.

This specific 250-250-250-250-3/0 size is typically used for:

• Main panel feeds in large residential buildings or light commercial installations, supporting up to 225A service.
• Subpanel feeds for multi-unit dwellings, apartments, or small commercial properties.
• Power distribution from meter bases to 200A or 225A panelboards.
• Feeding high-power electrical equipment such as HVAC systems, electric furnaces, and large appliances.
• Backup generator connections, where 225A-rated feeder is required.

Standards:

• Ampacities based on National Electric Code, 2005 edition, section 310-15 

• 60°C when terminated to equipment for circuits rated 100 Amps or less or marked for 14 gauge through 1 gauge conductors 

• 70°C when terminated to equipment for circuits rated over 100 Amps or marked for conductors larger than 1 gauge 

• 90°C wet or dry locations 

• For dwelling units, conductors shall be permitted at listed ampacities to be utilized as 120/240 volt, 3-wire, single phase service conductors that supply the total load 

• UL 44

Construction

Conductors:

The 250-250-250-250-3/0 designation means this cable contains:

• Four 250 AWG aluminum phase conductors (hot wires),
• One 3/0 AWG neutral conductor,
• One 3/0 AWG bare aluminum ground conductor.
• The conductors are compact stranded soft-drawn 8000 series aluminum, designed to transmit electric current.

Insulation:

Aluminum SER cable has a type XHHW-2 cross linked polyethylene (XLP) insulation. The conductors are cabled together with a bare aluminum ground and covered with a reinforced binder tape. For color code, see table B in the technical section. 

Jacket:

The cable jacket used in its design is Polyvinyl Chloride (PVC). The jacket protects the inner components of the cable from potentially damaging external forces. PVC is robust and resistant to oil, sunlight, water, flames, acids, chemicals, radiation, impact, abrasion, and weather changes. Sequential footage markings that help the user identify the appropriate length during installation are noted on the cable jacket.

Specifications:

• Insulated Cond(s) Size AWG: 250

• Bare Conductor Size AWG: 3/0

• Nominal O.D. Inches: 1.798

• Approx. Weight lb/1000FT: 1404 lbs

• Ampacity at 90°C: 230 Amps

• Ampacity in dwelling: 225 Amps