General Application Precautions - YASKAWA L1000A Technical Manual

i.2 General Safety

◆ General Application Precautions

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Motor Selection
Drive Capacity
The output current should not exceed 150% of the drive rated current. Select a drive that can output enough current when
accelerating a load at 100%.
For specialized motors, make sure that the motor rated current is less than the rated output current for the drive.
Starting Torque
The startup and acceleration characteristics of the motor are restricted to the drive's overload current rating (150% rated
current for 60 s).
The overload rating for the drive determines the starting and accelerating characteristics of the motor. Expect lower
torque than when running from line power. To get more starting torque, use a larger drive or increase both the motor and
drive capacity.
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Stopping
Fast Stop
When the drive faults out, a protective circuit is activated and drive output is shut off. This, however, does not stop the
motor immediately. Some type of mechanical brake may be needed if it is necessary to halt the motor faster than the Fast
Stop function is able to.
Mechanical Brake
When the drive faults out, the output shuts off but the motor does not stop when elevator is in unbalanced weight
condition. A mechanical brake is required.
Repetitive Starting/Stopping
Elevators and other applications with frequent starts and stops often approach 150% of their rated current values. Heat
stress generated from repetitive high current will shorten the life span of the IGBTs.
Yaskawa recommends lowering the carrier frequency, particularly when audible noise is not a concern. It is beneficial to
reduce the load, increase the acceleration and deceleration times, or switch to a larger drive to help keep peak current
levels under 150%. Be sure to check the peak current levels when starting and stopping repeatedly during the initial test
run, and make adjustments accordingly.
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Installation
Enclosure Panels
Keep the drive in a clean environment by installing the drive in an enclosure panel or selecting an installation area free of
airborne dust, lint, and oil mist. Be sure to leave the required space between drives to provide for cooling, and take proper
measures so the ambient temperature remains within allowable limits and keep flammable materials away from the drive.
Yaskawa offers protective designs for drives that must be used in areas subjected to oil mist and excessive vibration.
Contact Yaskawa or your Yaskawa agent for details.
Installation Direction
NOTICE: Install the drive upright as specified in the manual.
installation. Failure to comply may damage the drive due to improper cooling.
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Settings
DC Injection Braking
NOTICE: Excessive current during DC Injection Braking and excessive duration of DC Injection Braking can cause motor overheat.
Acceleration/Deceleration Ramp
Acceleration and deceleration times are affected by the amount of torque generated by the motor, the load torque, and the
inertia moment. Set a longer accel/decel time when Stall Prevention is enabled. The accel/decel times are lengthened for
20
Refer to Mechanical Installation on page 39
YASKAWA ELECTRIC SIEP C710616 38A YASKAWA AC Drive L1000A Technical Manual
for more information on