Aerotech Ndrive HPe 10, Руководство по оборудованию

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80 Chapter 2 www.aerotech.com
2.10. -EXTSHUNT Option (TB103)
The -EXTSHUNT option provides a connection for a user-provided shunt resistor to dissipate excess energy
and keep the internal drive voltage within safe levels. The drive switches this resistor "ON" when the internal
bus voltage reaches approximately 380 VDC. This option is generally required for systems that have a large
amount of stored mechanical energy ( i.e. large rotating drums).
Proper sizing, mounting, and protection of the shunt resistor is critical due to the potentially large amounts of
power dissipated.
D A N G E R : The shunt resistor temperature can exceed 70°C during normal operation and
contains lethal voltage on its terminals and surface. It must be properly enclosed and shielded
to avoid risk of fire and operator shock.
Table 2-49: -EXTSHUNT Component Information
Component Description Aerotech P/N
Recommended Shunt Resistor
50 Ω (min), 300 W
Vishay/Dale: RBEF030050R00KFBVT
ECR01039
2-Pin Mating Connector
Screw Torque Value : 0.5 - 0.6 N·m
Wire Size : 12-30 AWG [3.3 - 0.0516 mm
2
]
Phoenix:175449
ECK01110
Fuse (F2 on the Power Board)
2.5 A S.B.
Littelfuse: 21502.5P
EIF01053
Recommended Wire Size
16 AWG (1.3 mm
2
) High Temperature
--
The first step in sizing the external shunt resistor is to calculate the kinetic energy of the system ( Equation
1 ). Neglecting the system's losses, this is the energy that can potentially be regenerated to the DC bus.
Equation 1:
or
(for rotary motors) (for linear motors)
J
M
rotor inertia (kg·m
2
)
J
L
load inertia (kg·m
2
)
ω
m
motor speed before deceleration (rad/s)
M
M
forcer mass (kg)
M
L
load mass (kg)
v
m
velocity (m/s)
A shunt resistor is required if the regenerated energy is greater than the additional energy that the internal bus
capacitor can store (
Equation 2 ).
Ndrive HPe 10/20/30 Installation and Configuration