Marantec MDF-D400 Hand Chain Mechanism MDF 50

The Marantec MDF-D400 Hand Chain Mechanism (MDF 50 – KE) is a heavy-duty manual emergency chain-drive system designed for MDF 50 series industrial operators, typically used in higher torque applications (~500 Nm and above).

It provides ground-level manual operation via a continuous loop chain, allowing safe and controlled door movement when:

• Power supply fails
• Control faults occur
• Maintenance or commissioning is required

Within Marantec terminology:

• KE = “Kettenbetrieb” (hand chain operation)
• It is the standard emergency override for larger industrial drives

Key Features

• Heavy-duty emergency hand chain (KE)
• Designed for MDF 50 operator platform (incl. D400/D500 class systems)
• Enables floor-level operation for large doors
• Continuous loop chain for smooth manual control
• Integrated safety interlock switch
• Compatible with high torque industrial door systems
• Suitable for roller shutters and large sectional doors

Marantec confirms MDF systems support:

• “Emergency operation via… emergency hand chain ‘KE’”

Technical Specifications

(Based on MDF 50 / high-torque configurations such as MDF 30-50-12 and related models)

How It Works

• The gearbox includes a chain wheel mechanism
• Pulling the chain:
  • Engages manual override
  • Rotates the worm gear
  • Drives the door shaft directly
• Electrical operation is automatically disabled (interlocked) during manual use

This allows safe manual control of very heavy doors from ground level.

MDF 50 vs MDF 30 (Key Difference)

The MDF 50 range is part of Marantec’s higher torque class (up to 750 Nm and beyond)

Typical Applications

• Large industrial roller shutter doors
• High-mass sectional doors
• Warehouses and logistics hubs
• Manufacturing plants
• Installations with high door weight and frequent cycles

Especially suited where:

• Operator is mounted high
• Door mass requires high torque manual control

Safety & Functional Notes

• Includes:
  • Safety interlock switch (prevents powered operation during manual use)
  • Integrated safety catch (anti-drop)
• Designed for:
  • Controlled manual movement of heavy loads
  • Safe operation during power outages

Integration in MDF Systems

The MDF 50 KE mechanism is:

• Factory-installed or specified as an option
• Integrated with:
  • Worm gear transmission (phosphor bronze worm wheel)
  • Limit systems (AWG encoder or MEC switches)
  • Marantec CS control units

It is part of a modular system that also supports:

• KU (hand crank)
• E/KE (chain + maintenance release)

(The Company reserves the right to amend product specifications and information without notice.)