Technical information

57
Installation
Holding Brake Option
You can order a DX motor with an optional holding brake. The holding brake holds the motor
shaft whenever power is removed from the brake coil (as in a power failure).
This type of holding brake must not be used to stop the motor and load unless a power loss
situation occurs.
You can control the brake through an input line. You must assign Brake Override (Input
Function 13) to one of the input lines using PCX (See “Input Functions” on page 90).
You also need to consider the mechanical engagement and disengagement times during
system operation. (See “Holding Brake Specifications” on page 161 for additional brake
specifications).
Note
It should be noted that the brake option adds length to the motor.
Any application that allows the motor to be “back driven” when power is removed (a
condition where the load is causing the motor to rotate) should have provision for a holding
brake. Backdriving the motor can damage the drive or cause injury. This is especially
applicable when driving high inertial loads, loads that can store energy (i.e., pendulum or
offset loads), or any vertical application.
Holding Brake Control Circuit
A schematic representation of the brake control circuit is shown in Figure 44: "Optional Brake
Wiring Diagram" .
The suppression circuitry is polarity sensitive. Damage will occur to the motor or
amplifier or both if wiring polarity is not correct.
You must supply the brake wires for motors without connectors.
You must also provide the DC power supply for the brake. This voltage source must be
+24VDC with minimum current requirements. If you use this voltage source to power other
accessories or more than one brake, you must increase the current capability.