Hitachi BRD-E2-30K, Operation Manual

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(2) For use in two dynamic braking units
Table 9.2 For use in two dynamic braking units
Motor torque ratio %
E2 EZ2
30K 55K 30K 55K 110K
Rated torque of the motor
To: N.m (kgf.m)
4
Ω
2
Ω
10
Ω
6
Ω
3
Ω
Motor
(kW)
Inverter
(kW)
Moment of inertia J
for one motor (GD
2
)
kg.m
2
(kgf.m
2
)
50Hz 60Hz T
B
A T
B
A T
B
A T
B
A T
B
A
18.5 22.0 0.16 ( 0.64) 122 ( 12.4) 101 ( 10.3)
22.0 22.0 0.19 ( 0.76) 144 ( 14.7) 120 ( 12.2)
30.0 30.0 0.30 ( 1.20) 197 ( 20.0) 164 ( 16.7)
37.0 37.0 0.35 ( 1.40) 243 ( 24.7) 202 ( 20.6) 170
45.0 45.0 0.40 ( 1.60) 295 ( 30.1) 245 ( 25.0) 140 230
55.0 55.0 0.55 ( 2.20) 361 ( 36.8) 300 ( 30.6) 120 190
75.0 75.0 1.03 ( 4.12) 492 ( 50.2) 407 ( 41.5)
 
140 230
90.0 90.0 1.23 ( 4.92) 588 ( 60.0) 487 ( 49.6)
 
110 195
110.0 110.0 1.83 ( 7.32) 719 ( 73.3) 595 ( 60.7)
 
95 159
(3) Mean braking torque with one size bigger capacity
In a standard combination of a motor and an inverter, the braking torque is limited by the
overcurrent strength of the inverter. However, by increasing the rank of the inverter, you
can use the maximum torque of the motor.
Table 9.3 shows the braking torques of the inverters whose capacity is increased by one.
The motor capacity must be raised when 135% or more braking is required.
Table 9.3 Requirements for maximizing the braking torque of motor
(when the inverter capacity is increased by one)
Requirement:
‡ @
Mean braking torque 135% (To
×
1.35)
‡ A
Increasing the inverter capacity by one
‡ B
T
B
B
= 0.5
×
T
B
A
‡ C
The operation frequency and other conditions are
the same as those in Table 9.1 and Table 9.2.
Number of sets of dynamic braking units
and resistors required
E2 EZ2
30K 55K 30K 55K 110K
Rated torque of the motor
To: N.m (kgf.m)
4
Ω
2
Ω
10
Ω
6
Ω
3
Ω
Motor
(kW)
Inverter
(kW)
Moment of inertia J
for one motor (GD
2
)
kg.m
2
(kgf.m
2
)
50Hz 60Hz
T
B
A
T
B
A
T
B
A T
B
A T
B
A
18.5 22.0 0.16 ( 0.64) 122 ( 12.4) 101 ( 10.3) 1
22.0 22.0 0.19 ( 0.76) 144 ( 14.7) 120 ( 12.2) 1
30.0 30.0 0.30 ( 1.20) 197 ( 20.0) 164 ( 16.7) 2 1 1
37.0 37.0 0.35 ( 1.40) 243 ( 24.7) 202 ( 20.6) 2 1 1
45.0 45.0 0.40 ( 1.60) 295 ( 30.1) 245 ( 25.0) 2 1 2 1
55.0 55.0 0.55 ( 2.20) 361 ( 36.8) 300 ( 30.6)

2 2 1
75.0 75.0 1.03 ( 4.12) 492 ( 50.2) 407 ( 41.5)
 
2 2 1
90.0 90.0 1.23 ( 4.92) 588 ( 60.0) 487 ( 49.6)
  
2 1
110.0 110.0 1.83 ( 7.32) 719 ( 73.3) 595 ( 60.7)
  
2 1