Automatic Devices Company

A Track & Machine
For Every Purpose

Variable speed curtain machines

Variable speed lift and drawing machines offer features and protection not found on any other machines.  The machines are designed such that the operating speed, which is the speed between the acceleration and deceleration ramps, can be adjusted during set up to achieve the desired effect. The machines utilize constant torque motors and drives so no matter what the speed, the machine's torque remains at its listed level.

Variable machines are available for connection to 120 volt single phase, 220 volt single phase, 208 volt three-phase and 230 volt three phase power sources (voltage must be specified at time of order).

Some of the standard features of variable speed machines are:

  • Programmable acceleration ramp times.
  • Programmable deceleration ramp times.
  • Maximum obtainable speed (when speed pot is rotated to the maximum speed position).
  • Minimum obtainable speed (when speed pot is rotated to the minimum speed position).
  • Maximum obtainable current level.
  • Base frequency selection to help minimize noise.
  • Fault history archival.
  • Programmable LCD display.

Some optional features that are available are:

  • Dynamic brake resistors.
  • External brake signaling.
  • Network interface modules.
  • External fault indication.
  • Variable speed while running.

Please contact ADC directly regarding inquiries on variable speed curtain machines at