Demag DCS-Pro Variable-Speed Electric Chain Hoist

Overview

The Demag DCS-Pro is the variable-speed member of the Demag DC chain hoist family, combining the proven DC hoist mechanism with an integrated frequency inverter for infinitely variable lifting and lowering. Demag explains that sensitive parts can be lifted, lowered and positioned more smoothly, assembly and joining processes can be controlled more precisely, and handling can be faster thanks to the Pro-Hub function, which raises the lifting speed by up to 90% in the partial load and no-load range. The control unit and inverter are built in beneath the electrical equipment cover as a compact plug-in module, so the hoist needs hardly more space than a standard two-speed unit.

Seven Star LLC supplies the Demag DCS-Pro to precision assembly, maintenance and production customers in Oman and the GCC, with engineering support in Muscat. Our team helps buyers compare the variable-speed DCS-Pro with two-speed hoists and choose the size, hook path and travel drive that suit each workstation.

Operating Principle

As general engineering background, a frequency inverter controls the motor speed by varying the supply frequency and voltage, so the hoist motor can run at any speed between a very slow creep and full speed. On the Demag DCS-Pro this gives a control ratio of 1:100 and a creep hoist speed from 0.04 m/min, which Demag highlights as particularly fine control at low speeds for smooth starting and precise positioning. Acceleration and braking ramps prevent excessive load sway, and lifting speed and ramps can be modified through the control pendant if the application requires it.

The DSC-S control pendant uses PWM switching elements with a progressive characteristic over a 10 mm actuation path, which Demag compares to a car accelerator pedal: the further the button is pressed, the faster the hoist moves. The Demag DCS-Pro switches automatically to creep speed before the upper and lower end positions are reached, and a motor temperature monitoring device adds protection. Like the rest of the DC range, the load is held by a brake-coupling system in any operating situation, and a speed-monitored slipping clutch gives a safe cut-out in the event of overload.

Engineering Design of the Demag DCS-Pro

The Demag DCS-Pro accepts a 3-phase 380 to 480 V, 50 to 60 Hz wide voltage range input, uses 24 V control voltage with an operating limit switch, and is rated IP 55 for an ambient range of –20 to +40 °C. Demag gives a cyclic duration factor of 20% at the lowest hoist speed or 60% at rated speed and above. The Demag 2m+ classification provides, according to Demag, a 20% longer service life than FEM 2m units, and gearbox, brake and coupling are maintenance-free for up to 10 years. A modular chain drive can be replaced quickly without removing motor or gearbox parts.

Many functions are standard on the Demag DCS-Pro that other suppliers offer as extras: Plug & Lift and Plug & Drive connections, a pivoting service cover for access to connections, pendant height adjustment and chain lubrication, two suspension brackets, and an elapsed operating time counter with a diagnostics interface that service technicians can read from outside via a display or infrared data transmission. The hoist can be moved by hand on U11 to U34 push-travel trolleys or in the KBK rail system, and E11 to E34 electric travel drives give infinitely variable long and cross travel from 0.5 to 24 m/min, up to 30 m/min with partial loads.

Key Features

The following benefits are listed by Demag for the Demag DCS-Pro variable-speed chain hoist.

• Infinitely variable speed control applies to lifting and lowering over the whole load range.
• Creep speed from 0.04 m/min and a 1:100 control ratio allow gentle, precise positioning.
• Pro-Hub raises speed by up to 90% at partial load or no load for faster handling.
• Automatic switchover to creep speed happens before the upper and lower end positions are reached.
• Acceleration and braking ramps reduce load sway and can be adjusted from the pendant.
• A 380 to 480 V, 50 to 60 Hz wide voltage input suits different site supplies.
• Motor temperature monitoring and 24 V control voltage with operating limit switch improve safety.
• An elapsed time counter and diagnostics interface allow maintenance downtime to be planned.

Industrial Applications

Demag shows the variable-speed hoist handling glass panels, inserting shafts into lathe chucks and positioning coils in decoilers, which illustrates where the Demag DCS-Pro adds most value: fragile, expensive or tightly toleranced loads that must be set down gently. In Oman this includes valve and pump overhaul workshops where internals must be lowered into casings, electrical workshops handling motors and switchgear, glass and aluminium fabricators, machine shops loading CNC equipment and maintenance bays at power, water and oil and gas facilities. Faster partial-load speed also helps on busy assembly lines in the Sohar, Rusayl and Salalah industrial areas.

Seven Star LLC supplies the Demag DCS-Pro with matching trolleys, travel drives and pendants. Customers who only need two fixed speeds can compare the Demag DCS-Pro with the Demag DC-Com electric chain hoist, and those integrating hoists into larger crane systems often combine Demag units with drives such as the ABB ACS880-01 or the Schneider Electric ATV630 variable speed drive. Our Muscat engineers can help specify each lifting point from the Demag selection tables.

Technical Specifications

The Demag DCS-Pro values below come from Demag publication 229 326 49 and the DC at a glance brochure 213 737 44.

How to Order

To receive a quotation for the Demag DCS-Pro, send Seven Star LLC an RFQ with load capacity, hook path, required speed range, supply voltage and trolley or travel drive. Our team in Muscat will confirm the configuration against the Demag selection data and share the Demag brochure attached to this page. Seven Star LLC supplies Demag hoists and components to customers across Oman and the GCC.