15 "dc-injection braking" function, 0x2b80 | 0x3380 - dc-injection braking: current, 0x2b80 – Lenze i700 User Manual

Page 153: 0x3380, Dc-injection braking" function, 5motor control & motor settings

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Lenze · i700 servo inverter · Reference manual · DMS 1.5 EN · 03/2014 · TD05

153

5

Motor control & motor settings

5.15

"DC-injection braking" function

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5.15

"DC-injection braking" function

The control modes for asynchronous motors provide the opportunity to use "DC-injection braking"

for the braking process.
DC-injection braking can be

• parameterised via bit 6 in the Lenze control word (

0x2830

or

0x3030

for axis B) or

• as response to light errors.

Response of the device in the event of an error

( 262)

Cases of application

• for DC-injection braking via bit 6:

• The braking energy cannot be converted into heat in a brake resistor.
• An external control wants to request DC-injection braking with a drive in V/f operation.

• for DC-injection braking as response to light errors:

• Due to an encoder error, no quick stop is possible anymore.

Functional description
In this case, the motor control injects a DC current the amplitude of which can be set in the object

0x2B80

(or

0x3380

for axis B). For this purpose, it is required that the current control is adapted to

the corresponding motor.

Setting and optimising the current controller

( 105)

0x2B80 | 0x3380 - DC-injection braking: Current

Current amplitude for DC-injection braking

Note!

During the parameter setting of this object, it must be considered that a DC current amplitude is set here. In

contrast, the rated current of the motor is usually given as effective value. In order to prevent an overload of the

motor, the value set here should be at least lower by the factor "√2" than the rated motor current or attention

should be paid on a correspondingly set I²xt characteristic (

0x2D4D

or

0x354D

for axis B).

Setting range

(min. value | unit | max. value)

Lenze setting

0.00

A

500.00 0.00 A

Write access  CINH  OSC  P  RX  TX

Scaling: 1/100

UNSIGNED_16

Note!

The r.m.s. value of the current is calculated from the time values by means of the use of

the factor "√2". This also happens in case of the field frequency 0 Hz (DC current). In case

of the DC injection braking, the r.m.s. value is thus given by the factor "√ too low in

0x2DD1:5

(or

0x35D1:5

for axis B).

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