Delta ASD-B2-0121-B, User Manual

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Chapter 2 Installation and Storage
2-10
Revision June 2010
increase to 120°C or higher (on condition that when the regeneration continuously
occurred). For safety reasons, forced air cooling is good way that can be used to reduce
the temperature of the regenerative resistors. We also recommend the users to use the
regenerative resistors with thermal switches. As for the load characteristics of the
regenerative resistors, please check with the manufacturer.
External Regenerative Resistor
When using external regenerative resistor, connect it to P and C, and make sure the circuit
between P and D is open. We recommend the users should use the external regenerative
resistor that the resistance value following the above table (Built-in Regenerative Resistor
Specifications). We ignore the dissipative power of IGBT (Insulated Gate Bipolar Transistor) in
order to let the users easily calculate the capacity of regenerative resistor. In the following
sections, we will describe Regenerative Power Calculation Method and Simple Calculation
Method for calculating the regenerative power capacity of external regenerative resistors.
Regenerative Power Calculation Method
(1) Without Load
When there is no external load torque, if the servo motor repeats operation, the returned
regenerative power generated when braking will transmitted into the capacitance of DC
bus. After the capacitance voltage exceeds some high value, regenerative resistor can
dissipate the remained regenerative power. Use the table and procedure described below
to calculate the regenerative power.
Servo Drive
(kW)
Servo Motor
Rotor Inertia
J (× 10
-4
kg.m 2 )
Regenerative power
from empty load
3000r/min to stop
Eo (joule)
Max. regenerative
power of
capacitance
Ec(joule)
0.1 ECMA-C20401 0.037 0.18 3
0.2 ECMA-C20602 0.177 0.87 4
0.4
ECMA-C20604
ECMA-C20804
0.277
0.68
1.37
3.36
8
0.75 ECMA-C20807 1.13 5.59 14
1.0 ECMA-C21010 2.65 13.1 18
Low
Inertia
2.0 ECMA-C21020 4.45 22.0 21
0.4 ECMA-E21305 8.17 40.40 8
1.0 ECMA-E21310 8.41 41.59 18
1.5 ECMA-E21315 11.18 55.28 18
2.0
ECMA-E21320
ECMA-E21820
14.59
34.68 72.15
171.50
21
Medium
Inertia
3.0 ECMA-E21830 54.95 271.73 28