Yaskawa i80M Connecting Manual - Manual (Page 309)

: current
(Acceleration/decelerattion current a times the motor rated current) (A)
: Load current constant
: Current equivalent to load torque
(Load current times the meter rated current) (A)
Fig. A4. 2 Timing Chart of Motor Armature Current and Speed
A4. 3 ALLOWABLE FREQUENCY OF OPERATION
The allowable frequency of operation is restricted by the servomotor and Servopack, and both
the conditions must be considered for satisfactory operation.
Allowable frequency of operation restricted by the
The allowable frequency of operation is restricted by the heat generated in the regenerative re-
sistor in the Sarvopack, and varies depending on the motor types, capacity, JL,
acceleration/deceleration current values, and motor speed. If the frequency of operation ex-
c e e d s 60 when J L
= O before the rated speed is reached, or if it exceeds
cycles/rein when J
L
= COntaCt Yaskawa repreSentatiVe.
Allowable frequency of operation restricted by the Servomotor
The allowable frequency of operation varies depending on the load conditions, motor running
time and the operating conditions.
Typical examples are shown below. See par. A4. 2 Start-
ing and Stopping Time for symbols.
When the motor repeats rated-speed operation and being at standstill (Fig. A4. 3)
Cycle time (T) Should be determined so that RMS value of motor armature current is lower than
the motor rated current :
, ,
Where cycle time
specified.
(T) is determined, values tr, tf satisfying the formula above, should be
Fig. A4. 3 Timing Chart of Motor Armature Current and Speed
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