GE AF-650 GP Programming Manual page 149

Parameter Descriptions
3.21.3 B-2# Mechanical Brake
Parameters for controlling operation of an electro-magnetic (mechanical) brake, typically required in hoisting applications.
To control a mechanical brake, a relay output (relay 01 or relay 02) or a programmed digital output (terminal 27 or 29) is
required. Normally this output must be closed during periods when the frequency converter is unable to 'hold' the motor,
e.g. due to an excessive load. Select [32] Mechanical Brake Control for applications with an electro-magnetic brake in
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parameter E-24 Function Relay, parameter E-20 Terminal 27 Digital Output, or parameter E-21 Terminal 29 Digital Output. When
selecting [32] Mechanical brake control, the mechanical brake is closed from start up until the output current is above the
level selected in parameter B-20 Release Brake Current. During stop, the mechanical brake activates when the speed falls
below the level specified in parameter B-21 Activate Brake Speed [RPM]. If the frequency converter enters an alarm condition
or an over-current or over-voltage situation, the mechanical brake immediately cuts in. This is also the case during safe stop.
NOTICE
Protection mode and trip delay features (parameter SP-25 Trip Delay at Torque Limit and parameter SP-26 Trip Delay at
Drive Fault) may delay the activation of the mechanical brake in an alarm condition. These features must be disabled in
hoisting applications.
Illustration 3.45
148 02/2016 All rights reserved. DET-618D