Associated Equipment
5-7
AC30 series Variable Speed Inverter
Calculation
Brake resistor assemblies must be rated to absorb both peak braking power during deceleration and the average power over the
complete cycle.
Peak braking power P
0 0055
n
n
t
W
1
2
2
2
b
=
×
−
.
(
)
(
)
pk
×
J
J
- total inertia (kgm
2
)
n
1
- initial speed (rpm)
Average braking power P
P
t
av
pk
c
=
x t
b
n
2
- final speed (rpm)
t
b
- braking time (s)
t
c
- cycle time (s)
Obtain information on the peak power rating and the average power rating of the resistors from the resistor manufacturer. If this
information is not available, a large safety margin must be incorporated to ensure that the resistors are not overloaded.
By connecting these resistors in series and in parallel the required braking capacity can be selected for the application.
The minimum resistance of the combination and maximum dc link voltage must be as specified in Appendix F:
“Technical Specifications” - Internal Dynamic Brake Switch.
Figure 5.2 Braking Resistor Derating Graph (Metal Clad Resistors)
0
20
40
60
80
100
120
0
25
50
75
100
125
150
175
200
% of Rated Power
Ambient Temp (C)
Resistor Derating Graph
chassis mounted
free air
Summary of Contents for LINKnet AC30P
Page 47: ...4 27 Installation AC30 series Variable Speed Inverter Basic Speed Control Wiring...
Page 49: ...4 29 Installation AC30 series Variable Speed Inverter Auto Manual Control Wiring...
Page 51: ...4 31 Installation AC30 series Variable Speed Inverter Raise Lower Trim Wiring...
Page 53: ...4 33 Installation AC30 series Variable Speed Inverter Presets Speeds Wiring...
Page 55: ...4 35 Installation AC30 series Variable Speed Inverter PID Control Wiring...
Page 153: ...Setup Wizard 9 28 AC30 series Variable Speed Inverter Figure 9 16 Charting Drive Parameters...
Page 161: ...10 8 Trips Fault Finding AC30 series Variable Speed Inverter...