External panel mounted dc fuse, External panel mounted dc fuse 1, Standard braking resistors – GE Industrial Solutions 6KBU300 Braking Unit User Manual
Page 27
6KBU300
—————— STANDARD BRAKING RESISTANCES ——————
6
1
6. STANDARD BRAKING RESISTORS
In order to simplify the choice of the resistor that has to be used, here below the values of the normalized resistors
are reported, calculated on a criterion for a typical use.
P
OVL
Overload power that can be regenerated by the inverter, equal to the rated power mul-
tiplied by factor 1.36 (inverter’s overload = I
cont
x 1.36)
P
AVBR
Average power dissipated by the resistor, where the duty cycle is equal to 10%
E
B R
Maximum instantaneous energy that the resistor can dissipate
t
OVLBR
Maximum continuative braking time in overload conditions (P
OVL
)
t
B R
Maximum continuative braking time at drive rated load conditions
P
N B R
Rated continuous power of the resistor which must be equal or greater than the average
power P
AVBR
T
C
P,n
P
PBR
T
BR
n
E
BR
t
The ohmic value of the normalized resistors has been calculated in order to assure the braking current for the limit
use of 6KBU300, that is to say a 460Vac supply of the inverter (braking threshold 745Vdc).