Hard Wire Base Block (Hwbb) Function; Precautions For The Hard Wire Base Block (Hwbb) State - YASKAWA UAK series User Manual

8.8

Hard Wire Base Block (HWBB) Function

The Hard Wire Base Block function (hereinafter referred to as HWBB function) is a function designed to
baseblock the motor (shut off the motor current) by using the hardwired circuits.
This section describes the HWBB signals (/HWBB1 and /HWBB2) for a single axis of the servo drive.
Each circuit for two channel input signals blocks the run signal to turn off the power module that controls the
motor current, and the motor current is shut off. (Refer to the diagram below.)
24-V power supply
0 V
Note: For HWBB function signal connections, the input signal is the 0 V common and the output signal is the source out-
put. This is opposite to other signals described in this manual. To avoid confusion, the ON and OFF status of signals
for HWBB function are defined as follows:
ON: The state in which the relay contacts are closed or the transistor is ON and current flows into the signal line.
OFF: The state in which the relay contacts are open or the transistor is OFF and no current flows into the signal line.

8.8.1 Precautions for the Hard Wire Base Block (HWBB) State

Observe the following precautions in the HWBB state.
• The motor will rotate in an application where external force is applied to the motor (for example, gravity on
the vertical axis). Take measures to secure the motor, such as installing a mechanical brake.
• The motor may move within the electric angle of 180 degrees in case of the power module failure, etc. The
spindle motor coasts to a stop. Make sure that safety is ensured even in that situation. The rotation angle
depends on the motor type. The maximum rotation angle is given below.
Rotational motor: 1/6 rotation max. (rotation angle at the motor shaft)
• The HWBB function does not shut off the power to the SERVOPACK or electrically isolate it. Take mea-
sures to shut off the power to the SERVOPACK when performing maintenance on it.
This HWBB function is not relevant to Machinery directive, 2006/42/EC.
Switch

8.8 Hard Wire Base Block (HWBB) Function

Power supply
Control
circuit
Block
Block
Power module
Motor
8
8-37