SER Service Entrance Cable
WesBell SER (Service Entrance Round) cable comes in round and flat. Flat Service Entrance cable is designated as SEU cable. Please call if you need the flat version and ask for SEU cable. It's used to bring power from telephone poles to homes in order to supply about 200 AMPS to an electrical box. Then the electrical box allocates the 200 AMPS throughout the home by sending about 10 AMPS to each outlet and up to 50 AMPS for appliances. It's used in wet or dry locations at 90°C and 600 volts.
Service Entrance Cable Construction
Electrical cables are not designed to be flexible because once they are installed they are left for life, so adding flexibility would be a waste of money and time. The cable starts with bare copper covered by thermoplastic THHN insulation and a nylon coating. There is an additional bare copper ground wire (not insulated) and all of the conductors are covered with a gray PVC jacket. There aren’t any fillers in the cable to make it perfectly round so you’ll see exactly how the jacket hugs to the conductors and the outer diameter will vary depending on where it’s measured.
SER Cable Approvals
Some of the approvals listed on the specification sheet include ASTM, UL83, UL854, AA59544, RoHS and REACH. ASTM is the type of copper and according to their website, “ASTM's copper standards are instrumental in classifying, evaluating, and specifying the material, chemical, mechanical, and metallurgical properties of copper materials, including bronze and their alloys with other metals.” UL854 is mentioned on UL’s website as “Type SE (above-ground) power cables for installation in accordance with Article 338 and other applicable parts of the National Electrical Code (NEC). These cables are for the service-entrance and other (NEC) uses..”
AA59544 is just a federal identification numbering system while RoHS and REACH both restrict and measure levels of certain metals such as lead. For instance, tin and solder using lead are not RoHS approved.
Service Entrance Cable Applications
Generally, service entrance refers to the cable that starts on the telephone pole and connects to a home or building. From there it travels to the electrical box and supplies it with about 200 AMPS. Then the 200 AMPS are allocated in smaller amounts, with smaller cables (NMB Cable), to run power to light switches and outlets. SER cannot be buried underground without the use of conduit, instead tray cable or UFB cable should be used for direct burial applications. Otherwise, service entrance cables can be used for various outdoor applications that get installed and left for the life.
SER Cable Manufacturers
Several manufacturers design and make these cables but WesBell only uses Southwire and Encore Wire due to their quality of service and product. Not all manufacturers go the extra length of getting UL, RoHS and REACH approvals, nor are they quick about sending the backup data to prove the approvals. However, Southwire and Encore Wire are bout excellent manufacturers that stand behind their product and have open doors to prove anything you wish.
Tray cable is similar but can be direct buried in the ground, so applications such as service entrance can still use different cables to get the job done. For instance, both cables use THHN conductors and have bare copper ground wires, but tray cable has a different style of PVC jacket that’s approved to be used directly in the ground for life. With that comes a slightly higher price, so be sure you know how you’ll be installing the cable before you purchase something at a price that won’t prove a return on investment.
- Bare copper
- THHN insulation
- PVC Jacket
- Convey power from service drop to meter base
- Convey power from meter base to distribution panelboard
- Wet and dry locations