Emotron VS10 - Inverter Motor Brake

10.5.2. Inverter motor brake
With this braking method, which can be selected in 0x2541:001 (P706.01), the
regenerative energy in the motor is converted as a result of dynamic
acceleration/deceleration with downramping of the ramp function generator.
NOTICE
Too frequent braking may cause thermal overload of the motor.
▶ Avoid activating the "Inverter motor brake" function over a longer time!
▶ In applications with a high mass inertia and long braking times (> 2 s), use the "DC braking" function.
Preconditions
• The "Inverter motor brake" braking method must not be used with vertical conveyors
(hoists) or with active loads!
• The "inverter motor brake" braking method only works in operating mode 0x6060
(P301.00) = "MS: Velocity mode [-2]".
• When this braking method is used, the motor overload monitoring is not adapted. A
too frequent use of the inverter motor brake may cause an incorrect operation of the
motor overload monitoring. Motor overload monitoring (i²*t)
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Details
During the deceleration process, the ramp function generator is stopped. The frequency
set in 0x2541:004 (P706.04) is added to the frequency setpoint, taking the sign of the
current actual frequency into consideration. Furthermore the ramp function generator is
stopped in a state of overvoltage. If the DC-bus voltage falls below a defined DC-bus
voltage potential, the additional frequency connected is reduced again and the ramp
function generator is re-activated. By the alternating acceleration and deceleration
resulting from this circuit, the energy is converted thermally in the motor. For process-
related reasons, torque oscillations may occur.
Setting instructions
Generally, the smallest value possible required by the application for being able to still
traverse the load to be moved in a controlled fashion should be set as additional
frequency. Greater mass inertia values require an increase in the rated motor frequency
set. Increasing the rated motor frequency, however, causes greater torque oscillations. A
possible consequence is the reduced service life of mechanical components. Furthermore
an increase in the rated motor frequency also increases the energy converted into heat in
the motor. A possible consequence is the reduced service life of the motor.
Parameter
Name / value range / [default setting]
Info
0x2541:004
(P706.04)
Brake energy management: Additional frequency
(Brake management: Add.frequency)
0.0 ... [0.0] ... 10.0 Hz
Frequency deviation which is connected to the deceleration ramp in a
pulsative fashion when the "Inverter motor brake" braking method is
used.
0x2C01:005
(P320.05)
Motor parameters: Rated frequency
(Motor parameters: Rated frequency)
Device for 50-Hz mains: 1.0 ... [50.0] ... 1000.0 Hz
Device for 60-Hz mains: 1.0 ... [60.0] ... 1000.0 Hz
General motor data.
Carry out settings as specified by motor nameplate data.
Note!
When you enter the motor nameplate data, take into account the phase
connection implemented for the motor (star or delta connection). Only
enter the data applying to the connection type selected.
0x6060
(P301.00)
Modes of operation
(Modes of op.)
Setting can only be changed if the inverter is
inhibi
ted.
Selection of the operating mode.
-2
MS: Velocity mode
Vendor specific velocity mode
-1 MS: Torque mode (from version 03.00) Vendor specific torque mode
Only possible in motor control type 0x2C00 (P300.00) = "Sensorless
vector control (SLVC) [4]".
 Torque control w/ freq. limit

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