Laser Level Transmitter (ABB LLT100)

Where radar's wide beam picks up silo walls, ladders and agitators, or where the product's dielectric constant is too low to reflect a microwave, a laser gives a clean answer. The ABB LLT100 emits a pulsed laser beam that stays narrow over its entire range and measures time of flight to the product surface, whatever the material: black powder, white polymer pellets, clear liquid, wood chips or a moving object. It can aim through a small nozzle or a mesh, down a chute or at an angle, and it needs no calibration on installation.

Range is up to 100 m on solids and 30 m on liquids, with positioning applications to 200 m. Process conditions reach 49.6 bar and, with the cooling tube, 280 °C. The housing is aluminium or 316L stainless steel with a borosilicate or fused-glass window; mounting is top-mounted on ASME Class 150/300 or PN16/PN40 flanges or a Tri-Clamp, with a swivel flange and alignment laser to point the beam precisely. A dust tube and purge ring keep the window clear in dusty silos and a heated window prevents condensation.

Output is 4–20 mA HART.

Applications are solids level in silos, hoppers and bunkers, liquid level in tanks and sumps, mixer and crusher monitoring, and position measurement of cranes, stackers and vehicles across mining, aggregates, cement, petrochemical, chemical, food and beverage, power generation and water.