4. CONTROL OF VIX DRIVES 69External Brake Control
The base drive (AE version) has a dedicated input (X5 pin10) used for external control of the
brake. This input can be driven from a high-level logic source or sink, or a low-level logic
source, see Brake Input Circuit in Electrical Installation section. A logic high input is
required to apply or engage the brake, the brake will react immediately with no delay or
check for motor movement. Select mode E using the BRAKE command to make use of this
external input.
Use this form of brake control with caution, since careless or accidental application of the
brake could lead to physical damage of the brake components.
Default Brake Command
For the base drive, the BRAKE default setting is all brake modes disabled.
Other Factors that Influence Braking Operation
In addition to the modes of brake operation, certain drive conditions influence brake
behaviour, these are:
• State of enable input
• Resetting the drive
• 24V power failure
• Drive fault
Enable Input
Even if the motor is moving, setting the enable input to disable would immediately disable
the drive’s power stage. If the automatic dynamic brake mode is set, the brake is applied as
soon as the controller detects the drive is de-energised (nominally within 500 microseconds).
If the input is subsequently re-enabled, the brake remains applied until released by a valid
control method.