Danfoss VLT AutomationDrive FC 302 Programming Manual page 64

Parameter Descriptions
2-18 Brake Check Condition
Range:
[0] At Power Up
*
[1] After Coast Situations Brake check is performed after coast
3 3
2-19 Over-voltage Gain
Range:
100 % [0 - 200 %]
*
3.4.3 2-2* 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]
Start
1=on
term.18
0=o
Par 1-71
Start delay time
Shaft speed
Output current
Pre-magnetizing
current or
DC hold current
Par 2-23
Brake delay time
Relay 01
Mechanical brake
locked
Mechanical brake
free
Illustration 3.19 Mechanical Brake
62
VLT
Function:
Brake check is performed at power-
up.
situations.
Function:
Select overvoltage gain.
Par 1-74
Start speed
Par 1-76 Start current/
Par 2-00 DC hold current
Reaction time EMK brake
on
o
Danfoss A/S © Rev. 10/2014 All rights reserved.
®
AutomationDrive FC 301/302
Mechanical Brake Control for applications with an electro-
magnetic brake in parameter 5-40 Function Relay,
5-30 Terminal 27 Digital Output, or 5-31 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 2-20 Release Brake Current. During stop, the
mechanical brake activates when the speed falls below the
level specified in parameter 2-21 Activate Brake Speed [RPM].
If the frequency converter enters an alarm condition or an
overcurrent or overvoltage situation, the mechanical brake
immediately cuts in. This is also the case during Safe
Torque Off.
NOTICE
Protection mode and trip delay features
(parameter 14-25 Trip Delay at Torque Limit and
parameter 14-26 Trip Delay at Inverter Fault) may delay
the activation of the mechanical brake in an alarm
condition. These features must be disabled in hoisting
applications.
Par 2-20
Release brake current
Par 2-21
Activate brake
speed
Time
MG33MJ02