Dimensioning; Important Notes - Lenze EMB9351-E Instructions De Mise En Service

5

Dimensioning

Important notes

5 Dimensioning
5.1 Important notes
(
Stop!
Thermal overload of brake chopper EMB9352 or of the brake
resistor.
If the value falls below the brake resistance R
maximum running time of the brake chopper / brake resistor is
exceeded, the components will be overloaded.
Possible consequences:
ƒ
Protective measures:
ƒ
ƒ
ƒ
Brake
resistance R
76
The components fail.
Always implement the temperature monitoring of the brake
resistor into the emergency stop chain.
Please observe the running time t
brake resistor and the brake chopper.
Calculate the generated braking energy of the application for
brake resistances <R
– Connect the brake chopper in parallel if the maximum values
of the brake chopper are exceeded.
EMB9352
U = 375 V U = 725 V
ch ch
U = 765 V
ch
= 27 W R = 54 W
R
B,lim B,lim
<27 W <54 W
B
³27 W ³54 W
and dead time t
on
. (¶ 79)
B,lim
Dimensioning steps
1. Calculate running time and dead time. (
– Condition "t + t
on
2. Dimension brake chopper and brake resistor .
^
( 79)
1. Calculate running time and dead time. (
– The technical data of the brake resistor must be
observed.
l
or if the
B,min
of the
off
^
77)
= 3 s" must be observed.
off
^
77)
EDBMB935X DE/EN/FR 12.0