Resistor Choice - ABB MicroFlex e190 User Manual

the average power dissipation. This average value can be used to represent an
equivalent continuous braking power, where C is the cycle time (see page 173):

= P
P
gen,ave gen,max

= ________________ W (watts)

Calculate the maximum braking power P
braking power P
gen,ave


Resistor choice

P is the value to use when assessing which brake resistor to use. However, a
gen,ave
safety margin of 1.25 times is recommended to ensure the resistor operates well
1
within its limits , so:

Required resistor power rating = 1.25 × P

________________ W (watts)
The range of suitable brake resistors is shown in the following table. Choose the
resistor that has a power rating equal to or greater than the value calculated above.
Part
RGJ139
RGJ160
RGJ260
RGJ360
WARNING! The brake resistance must be 39 Ω or greater to ensure the
drive's maximum regeneration switching current (10 A) is not exceeded.
Failure to observe the minimum resistance could result in damage to the drive. See
Brake resistor connection
1. The brake resistors listed in the following table can withstand a brief overload of 10 times
the rated power for 5 seconds. Please contact ABB if larger power ratings are required.
D
×
C
for the motor.
Resistance
39 Ω
60 Ω
60 Ω
60 Ω
on page 154.
and the equivalent continuous
gen,max

gen,ave
Resistor braking 175
Power rating
100 W
100 W
200 W
300 W