![background image](http://html.mh-extra.com/html/vlt/automationdrive-fc-300/automationdrive-fc-300_instruction-manual_1042927034.webp)
Additional Connections
Mechanical Brake Control
In hoisting/lowering applications, it is necessary to be able to control an electro-mechanical brake.
•
Control the brake using any relay output or digital output (terminal 27 or 29).
•
Keep the output closed (voltage-free) as long as the adjustable frequency drive is unable to
‘support’ the motor, such as when the load is too heavy, for example.
•
Select
Mechanical brake control
[32] in par. 5-4* for applications with an electro-mechanical
brake.
•
The brake is released when the motor current exceeds the preset value found in par. 2-20.
•
The brake is engaged when the output frequency is less than the frequency found in par. 2-21
or 2-22, and only if the adjustable frequency drive carries out a stop command.
If the adjustable frequency drive is in alarm mode or in an overvoltage situation, the mechanical brake
immediately cuts in.
Parallel Connection of Motors
The adjustable frequency drive can control several
parallel-connected motors. The total current con-
sumption of the motors must not exceed the rated
output current I
M,N
for the adjustable frequency
drive.
Parallel motor connection is only recommended
when U/f is selected in par. 1-01.
NOTE
Installation with cables connected in a
common joint as in illustration 1 is only
recommended for short cable lengths.
NOTE
When motors are connected in paral-
lel, par. 1-02
Automatic Motor Adap-
tation (AMA)
cannot be used, and par.
1-01
Motor Control Principle
must be
set to
Special motor characteristics
(U/f)
.
Problems may arise at start and at low RPM values if motor sizes are widely different, because small
motors' relatively high ohmic resistance in the stator calls for a higher voltage at start and at low RPM
values.
VLT
®
AutomationDrive FC 300 Instruction Manual
How
to
Install
34
MG.33.A8.22 - VLT
®
is a registered Danfoss trademark.