138
Process and Application Parameters [300]
Section 11-3
11-3-4 Mechanical brake control
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.
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.
Communication information
Fig. 73 shows the relation between the Brake functions.
•
Brake Release Time [33C]
•
Start Speed [33D]
Default:
0.00 s
Range:
0.00–3.00 s
Modbus Instance no/
DeviceNet no:
43112
Profibus slot/index
169/16
EtherCAT index (hex)
4c28
Fieldbus format
Long, 1=0.01 s
Modbus format
EInt
0.00s
A
Summary of Contents for SX-F
Page 2: ......
Page 14: ...6 Table of contents...
Page 20: ...12 Glossary Section 1 6...
Page 32: ...24 Cabinet mounting Section 2 3...
Page 58: ...50 Connecting options Section 5 6...
Page 72: ...64 Load Monitor and Process Protection 400 Section 7 5...
Page 74: ...66 EMC standards Section 8 1...
Page 266: ...258 System Data 900 Section 11 9...
Page 274: ...266 Maintenance Section 12 3...
Page 284: ...276 Liquid cooling Section 13 12...
