Resistor braking 175
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
P
gen,ave
=
P
gen,max
×
D
C
=
________________ W (watts)
Calculate the maximum braking power P
gen,max
and the equivalent continuous
braking power P
gen,ave
for the motor.
Resistor choice
P
gen,ave
is the value to use when assessing which brake resistor to use. However, a
safety margin of 1.25 times is recommended to ensure the resistor operates well
within its limits
1
, so:
Required resistor power rating = 1.25 × P
gen,ave
________________ 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.
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
on page
.
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.
Part
Resistance
Power rating
RGJ139
39
Ω
100 W
RGJ160
60
Ω
100 W
RGJ260
60
Ω
200 W
RGJ360
60
Ω
300 W
Summary of Contents for MicroFlex e190
Page 1: ...ABB motion control User s manual MicroFlex e190 servo drive ...
Page 4: ......
Page 12: ...12 Table of contents ...
Page 26: ...26 Introduction to the manual ...
Page 90: ...90 Electrical installation input output ...
Page 146: ...146 Maintenance ...
Page 178: ...178 Resistor braking ...
Page 186: ...186 Accessories ...
Page 208: ...208 Appendix Safe Torque Off STO ...