DEMAG Hoist Rectifier Brake Module GS 26089484 110V-500V 1A

Engineer's Quick Brief

• Ultra-Wide Voltage Range: Engineered to safely accept AC input voltages anywhere from 110V to 500V AC, making it a universal spare part for various global factory electrical grids without risking diode breakdown.
• OEM Demag Compatibility: A direct, genuine replacement for Demag material handling equipment, ensuring precise DC voltage delivery to release the mechanical brake on heavy-duty hoist motors.
• Robust Solid-State Design: Fully encapsulated to withstand the severe mechanical vibrations, shock loads, and high ambient temperatures characteristic of overhead crane bridges and chain hoist trolleys.

SEO Introduction

The DEMAG GS 26089484 Rectifier Brake Module is a critical power conversion component designed specifically for Demag's renowned line of overhead cranes, wire rope hoists, and chain hoists. Its primary function is to convert the incoming Alternating Current (AC) from the crane's control panel into the stable Direct Current (DC) required to energize the electromagnetic brake coil. When energized, the brake releases, allowing the hoist motor to operate; when power is removed, the brake mechanically engages instantly for fail-safe load holding. Rated for an exceptionally wide input range of 110V to 500V AC and a maximum current of 1.0 A, this robust rectifier prevents brake chatter, ensures smooth lifting operations, and protects the hoist motor from burning out due to a locked rotor condition.

Technical Specifications

Application Matrix

• Overhead Bridge Cranes: Installed within the motor terminal box or central control cabinet to manage the braking sequences of large bridge-travel and trolley-travel motors.
• Chain & Wire Rope Hoists: Essential for the safe operation of vertical lifting motors. A functioning rectifier ensures the brake releases fully before the motor applies lifting torque, preventing catastrophic coil meltdown.
• Automated Material Handling: Provides rapid, repeatable brake engagement and disengagement in high-cycle Demag transfer carriages and manufacturing assembly lines.

Troubleshooting & FAQ

• The Demag hoist motor hums, but it won't lift, and I smell burning. What is wrong? This is the classic symptom of a failed brake rectifier. If the GS 26089484 module blows (fails open), it stops sending DC power to the brake coil. The mechanical brake remains locked, but the AC motor continues trying to turn against it. You must stop the hoist immediately to prevent the motor windings from burning out, and replace the rectifier.
• How can I test if the Demag 26089484 rectifier is defective? Ensure all power is locked out (LOTO). Remove the module and use a digital multimeter set to "Diode Test" mode. Test the paths between the AC input terminals and the DC output terminals. A healthy module will show a standard diode voltage drop (around 0.4V - 0.7V) in one direction, and "OL" (Open Line) in reverse. If you read a dead short (0 ohms) or "OL" in both directions across the active pins, the internal diode bridge is destroyed.
• Does this module output a fixed DC voltage regardless of the input? No. This is a critical misunderstanding. The rectifier converts AC to DC, but the output voltage is proportional to your input voltage. If you feed it 230V AC, it outputs the corresponding rectified DC (approx. 103V DC for half-wave). If you feed it 400V AC, it outputs a much higher DC voltage. You must ensure your brake coil's rated voltage matches the expected DC output of your specific electrical supply.
• Can I bypass the rectifier and power the brake coil directly? Absolutely not. Demag hoist brake coils are strictly DC components. Applying AC voltage directly to the DC brake coil will cause violent magnetic chattering, complete failure to lift the brake plate, and immediate destruction of the coil.

Cross-Reference Guide

When servicing legacy Demag equipment, identifying the correct rectifier is crucial for safety and operational integrity. The 26089484 is a highly versatile part, but always verify physical dimensions and wiring schematics:

• Demag System Compatibility: Widely compatible with older generations of Demag PK series and DK series chain hoists, as well as standard KBA/KBF conical rotor motors.
• Upgrade Note: If your hoist requires exceptionally fast brake application times (for millimeter-precision positioning), verify if your system originally specified a standard "GS" (half-wave) rectifier or a specialized fast-switching module before substituting.