Technical Manual for EA350 Analog Pulse Type Servo Driver V101 3.7 Holding brake When a motor is used to drive a vertical shaft or in other similar circumstances (such as presence of external force), to prevent motion of any moving part due to gravity or external force in case of power failure, the motor used shall have a holding brake. 1. A holding brake is only used to hold the motor in the stop position, and it may not be used to stop operation of a motor. 2. When the motor with a holding brake operates, the brake may produce clicks but this does not affect the function of the motor. Caution ☞ The holding brake requires provision of an external 24V power source.
Wiring diagram of the brake signal and brake power source is shown below: Fig. 3-21 Brake signal and brake power wiring 3.7.1 Precautions for wiring of the holding brake: 1) The intermediate relay must be controlled through the signal terminal (DO2+ and DO2- in the figure above) of function No. 2 (BK) defined by EA350 servo driver; connection and disconnection of the holding brake to power supply is controlled by the normally open contact of the intermediate relay. 2) The holding brake coil has no polarity; when powered on, it is released (at this time, the brake disc is separated without braking force). 3) The holding brake requires use of an external power source.
DC24V power supply to the intermediate relay coil can be sourced from the servo driver; when an external power source is used, it is not recommended to use the same power source with the holding brake. 4) When an external power is used for the intermediate relay coil, note that DO2+ terminal shall connect to the positive terminal of the power source and DO2- shall connect to the negative terminal of the power source. 5) For operation of the holding brake, it is required to ensure an input voltage of 21.5V; for this reason, full consideration shall be given to voltage drop resulted from the power cable resistance of the holding brake, and cable of 0.5mm 2 or above is recommended for use.
For specific power parameters of the holding brake, see Chapter 12. 6) The holding brake should preferably not share a power source with other appliances, so as to prevent operation of the other appliances resulting in voltage or current reduction and finally in malfunction of the holding brake. 41