4.8.4 Voltage/Current Input Selection
(Switches)
The analog input terminals 53 and 54 allow setting of
input signal to voltage (0–10 V) or current (0/4–20 mA).
Default parameter setting:
•
Terminal 53: Speed reference signal in open-loop
(see
16-61 Terminal 53 Switch Setting
).
•
Terminal 54: Feedback signal in closed-loop (see
16-63 Terminal 54 Switch Setting
).
NOTICE!
Disconnect power to the adjustable frequency drive
before changing switch positions.
1.
Remove the LCP (local control panel) (see
).
2.
Remove any optional equipment covering the
switches.
3.
Set switches A53 and A54 to select the signal
type. U selects voltage, I selects current.
130BD530.10
1
2
N O
VLT
BUSTER.
OFF-ON
A53 A54
U- I U- I
Figure 4.10 Location of Terminal 53 and 54 Switches
To run STO, additional wiring for the adjustable frequency
drive is required. Refer to
VLT
®
Adjustable Frequency Drives
Safe Torque Off Instruction Manual
for further information.
4.8.5 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 or 29).
•
Keep the output closed (voltage-free) as long as
the adjustable frequency 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
2-20 Release Brake
Current
.
•
The brake is engaged when the output frequency
is less than the frequency set in
2-21 Activate
Brake Speed [RPM]
or
2-22 Activate Brake Speed
[Hz]
, 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
closes.
The adjustable frequency drive is not a safety device. It is
the responsibility of the system designer to integrate
safety devices according to relevant national crane/lift
regulations.
L1
L2
L3
U
V
W
02
01
A1
A2
130BA902.10
Drive
Output
relay
Command Circuit
220Vac
Mechanical
Brake
Shaft
Motor
Frewheeling
diode
Brake
380Vac
Output
Contactor
Input
Power Circuit
Figure 4.11 Connecting the Mechanical Brake to the
Adjustable Frequency Drive
Electrical Installation
Instruction Manual
20
Danfoss A/S © Rev. 09/2014 All rights reserved.
MG33AP22
4
4
