Parker Aries AR-04CE - Resistor Specifications-Rotary Motors

Parker Hannifin
Appendix B External Power-Dump Resistor Selection - 93 -
Resistor Specifications—Rotary Motors
Having determined the amount of energy to dump (E
R
), you can then
calculate the resistor specifications.
• Maximum resistance
• Peak dissipation
• Average dissipation
Maximum Resistance
This calculation determines the maximum value of resistance needed for the
external power-dump resistor. We recommend that you select a lower value
resistance, typically in the 22 to 100 ohm range.
Important — It is possible to overload a drive/controller or the combination
of a drive/controller and power dump resistor.
If, at the end of the calculations, you find the required resistor is less than
allowed for your specific Aries Controller model, or requires a wattage rating
greater than the rated resistors available, do not use the unit in your
application.
Drive/controller models AR-04CE, AR-08CE, and AR-13CE require external
resistance values of 22 Ohms or greater.
()
ω ⋅+
⋅⋅
==
LM
DTTRIP
R
JJ
tkV
I
V
R
Where
R
R
= maximum external power dump resistance (Ohms)
V = voltage across the resistor (V
TRIP
)
I = current through the resistor (drive current required to decelerate
the load)(Amps
rms
)
V
TRIP
= power dump trip DC voltage (400 VDC)
k
T
= motor torque constant (Nm/Amp
rms
)
J
M
= rotor inertia (kg⋅m
2
)
J
L
= load inertia (kg⋅m
2
)
t
D
= deceleration time (Seconds)
ω = rotational speed in radians per sec (1 revolution/sec =
2⋅π⋅radians/sec)