EHS 1x7 Galvanized Steel Strand 3.6-5.2mm Low Sag Messenger for ADSS Fiber Cable

EHS 1x7 galvanized steel strand, 3.6mm to 5.2mm, extra high strength wire for ADSS and OPGW aerial cable where sag budget is tight.

Aerial fiber work lives or dies on sag. On a fixed span the messenger has to carry the cable at a tension low enough to protect the fiber and high enough to keep the cable out of the way of traffic, trees and other services. Extra high strength strand is how that balance is achieved without using a heavier strand that overloads the pole.

The wire in an EHS strand is drawn to around 1770 megapascals, which is roughly a quarter stronger than standard strand at the same diameter. That lets the designer work at a higher tension for the same sag, or the same tension with a smaller strand. We supply 3.6mm through 5.2mm because those are the sizes that appear on ADSS and OPGW hardware data sheets.

• 1770 MPa wire for real sag gains: Higher strength allows a shorter sag at the same support height, which is often the only way to clear a road or a building line without adding a pole.
• Diameter control for lashing and clamps: Messenger clamps, spiral lashing and dead end fittings are size specific. Our strand holds a tight diameter band so the hardware specified in the design actually fits on site.
• Galvanized for a 25 year span life: Standard coating mass of 215 to 260 grams per square metre, which is appropriate for inland and general industrial routes. Coastal routes should specify Class C.
• 1x7 for stiffness over long spans: Seven wires give a strand that resists galloping and holds its catenary shape in wind without the whipping that a finer construction can develop on exposed routes.
• Low relaxation for stable tension: Stress relieved wire keeps relaxation low, so the sag measured at commissioning is still the sag five years later and the clearance margins stay valid.
• Spooled for aerial stringing: Long continuous lengths on sturdy reels with served ends, so a span can be pulled without a mid span joint that would need a joint box and a splice crew.

The main use is as the messenger for ADSS and OPGW aerial fiber on distribution poles, including routes where clearance is tight and a heavier strand cannot be used because of pole loading limits.

It is also used for small aerial cable support in industrial plants, for catenary support of sensors and cameras along a route, and for tensioned support of lightweight signage where wind induced movement has to be controlled.

• ADSS aerial fiber messenger strand
• OPGW and skywrap support runs
• Distribution pole aerial cable support
• Industrial plant catenary for sensors and cameras
• Lightweight signage tensioned support

Tensile strength of the drawn wire is tested before stranding, and the finished strand is tested for breaking load and elongation per lot. Because EHS wire has less ductility, torsion and bending tests are run more frequently than on standard strand to catch wire that would crack under vibration.

Diameter is checked with a laser gauge at three points per reel and logged. We can supply the actual measured modulus and mass per metre for a lot when a designer needs to verify a sag tension calculation against delivered material.

Plywood or steel reels of 1000m to 5000m, ends served and welded, VCI wrapped and strapped for export. Reel dimensions are confirmed before booking so the stringing trailer and brake tensioner on site can handle them without improvisation.