Mechanical Brake Control - Omron SX-F Instruction Manual

Process and Application Parameters [300]

11-3-4 Mechanical brake control

138
The four brake-related menus [33C] to [33F] can be used to control mechani-
cal brakes e.g. to handle basic hoisting functions. When hoisting a load gener-
ally a mechanical brake holds the load when the VSD is not running. To
prevent the load from falling down a holding torque must be initiated before
the mechanical brake is released. On the other hand when stopping hoisting
the brake must be activated before the holding torque is removed.
Support is included for a Brake Acknowledge signal via a digital input. It is
monitored using a brake fault time parameter. Additional output and trip/warn-
ing signals are also included. The acknowledge signal is either connected
from the brake contactor or from a proximity switch on the brake.
The brake acknowledge signal can also be used to improve safety by prevent-
ing hoist falling load in case the brake is not engaged when stopping.
Brake not released - Brake Fault trip.
During start and running the brake acknowledge signal is compared to the
actual brake output signal and if no acknowledge, i.e. brake not realsed, while
brake output is high for the Brake Fault time [33H], then a Brake trip is gener-
ated.
Brake not engaged - Brake Warning and contiued operation
(Keep torque)
The brake acknowledge signal is compared to the actual brake output signal
at stop. If acknowledge is still active, i.e. brake not engaged, while brake out-
put is low for the Brake Engage time [33E] then a Brake warning is generated
and the torque is kept, i.e. prolonging normal brake engage mode, until brake
closes or an emergency action is needed by the operator, such as setting
down the load.
Brake Release Time [33C]
The Brake Release Time sets the time the VSD delays before ramping up to
whatever final reference value is selected. During this time a predefined
speed can be generated to hold the load where after the mechanical brake
finally releases. This speed can be selected at Release Speed, [33D]. Imme-
diate after the brake release time expiration the brake lift signal is set. The
user can set a digital output or relay to the function Brake. This output or relay
can control the mechanical brake.
Default:
Range:
Communication information
Modbus Instance no/
DeviceNet no:
Profibus slot/index
EtherCAT index (hex)
Fieldbus format
Modbus format
Fig. 73 shows the relation between the Brake functions.
• Brake Release Time [33C]
• Start Speed [33D]
33C Brk Release
Stp 0.00s
A
0.00 s
0.00–3.00 s
43112
169/16
4c28
Long, 1=0.01 s
EInt
Section 11-3