Bailey Specialty Cranes & Aerials has converted a JLG 660SJ telescopic boom lift from diesel power to 480V 3-phase plug-in electric power to meet the needs of a major theme park.
The park bought the 66-ft. tall, 500-lb.-capacity lift indoors to maintain a huge video display screen, so it wanted quiet, emission-free operation. The customer also requested that JLG paint the lift black to make it less visible. JLG shipped the brand new lift directly from its Pennsylvania factory to Bailey’s facility in metropolitan Milwaukee, Wis. When Bailey had completed conversion and testing, the lift was shipped to the park, where it was put right to work.
To make the conversion, Bailey removed the lift’s 67-hp diesel engine and all fuel-system components, then installed the 480V 3-phase electric motor, a motor-starter box, a 120V charger for the 12V battery that powers the emergency lowering system, and a 120V transformer. The electric motor was coupled to the lift’s existing hydraulic pump and the system pressure was reduced from 3,650 psi to 3,000 psi. to match the motor’s 15-hp capacity.
Going with a smaller electric motor helped save cost and reduce electric usage without affecting any function other than travel. Since the 660SJ is traveling a short distance on a paved and level floor, travel power and speed were not an issue. Travel speed with the electric motor is just 0.75 mph (vs 4.0 mph with diesel power), but all other functions work with the same speed and performance as in a diesel-powered version.
Since the electric motor weighed less than the original diesel engine, Bailey added counterweight to keep the lift’s center of gravity in its original spot, then put the converted 660SJ through a full battery of stability and function tests.
The conversion also included a wall-mounted reel with 50 ft. of electric cable that pays out and reels in as the lift travels the 30 ft. or so needed for its crew to do their work.
The entire process took about two weeks of engineering and six weeks of work and testing, according to Jeff Bailey, president of Bailey Specialty Cranes and Aerials.
Lift & Access is part of the Catalyst Communications Network publication family.
