Mechanical Brake Control - Danfoss VLT FC 280 Operating Manual

VLT® Midi Drive FC 280
Operating Guide

4.9.4 Mechanical Brake Control

In hoisting/lowering applications, it is necessary to control an electro-mechanical brake.
• Control the brake using any relay output or digital output (terminal 27).
• Keep the output closed (voltage-free) as long as the drive is unable to keep the motor at standstill, for example due to the load
being too heavy.
•
Select [32] Mechanical brake control in parameter group 5-4* Relays for applications with an electro-mechanical brake.
•
The brake is released when the motor current exceeds the preset value in parameter 2-20 Release Brake Current.
•
The brake is engaged when the output frequency is less than the frequency set in parameter 2-22 Activate Brake Speed [Hz], and
only if the drive carries out a stop command.
If the drive is in 1 of the following situations, the mechanical brake immediately closes.
• In alarm mode.
• In an overvoltage situation.
• STO is activated.
• Coast command is given.
Start Command
Off
Start Delay
Start Speed
MAV
0
Output Current
0
Active Brake Delay
/
Relay DO Status
Off
Activated
.
Mech Brake Status
1) DC injection current during "Active Brake Delay" after MAV reduced to "0" . Only support in some products.
Note:
2)
Only support in some products.
Illustration 18: Mechanical Brake
The drive is not a safety device. It is the responsibility of the system designer to integrate safety devices according to relevant na-
tional crane/lift regulations.
Danfoss A/S © 2022.02
On
Release Brake Current
Start Current
Reaction time of
.
mech brake
On
Reaction time of
.
mech brake
Released
AQ381425076031en-000101 / 130R1223 | 31
Electrical Installation
Off
Active Brake Speed
t
1)
DC Injection Current
t
2)
Active Brake Delay
Off
Activated