Yaskawa Z1000 AC Drive HVAC - Manual (Page 18)

50
3 6 60
60
70
80
90
100
25% ED (or 15 min)
40% ED (or 20 min)
60% ED (or 40 min)
Frequency (Hz)
Continuous operation
Torque
(%)
20
Figure i.2 Allowable Load Characteristics for a Yaskawa Motor
Insulation Tolerance
NOTICE: Consider motor voltage tolerance levels and motor insulation in applications with an input voltage of over 440 V or particularly
long wiring distances.
High-Speed Operation
NOTICE: Problems may occur with the motor bearings and dynamic balance of the machine when operating a motor beyond its rated speed.
Contact the motor or machine manufacturer.
Torque Characteristics
Torque characteristics differ compared to operating the motor directly from line power. The user should have a full
understanding of the load torque characteristics for the application.
Vibration and Shock
The drive allows selection of high carrier PWM control and low carrier PWM. Selecting high carrier PWM can help reduce
motor oscillation.
• Take particular caution when adding a variable speed drive to an application running a motor from line power at a constant
speed. If resonance occurs, install shock-absorbing rubber around the base of the motor and enable the Jump frequency
selection to prevent continuous operation in the resonant frequency range.
• Mechanical resonance can occur with long motor shafts and in applications such as turbines, blowers, and fans with high
inertia loads. Use Closed Loop Vector Control when these applications experience mechanical resonance problems.
Audible Noise
The audible noise of the motor varies based on the carrier frequency setting. However, drive current derating may be required.
When using a high carrier frequency, audible noise from the motor is comparable to the motor noise generated when running
from line power.
n Synchronous Motors
• Contact Yaskawa or a Yaskawa agent when planning to use a synchronous motor not endorsed by Yaskawa.
• Use a standard induction motor when running multiple synchronous motors simultaneously. A single drive does not have
this capability.
• A synchronous motor may rotate slightly in the opposite direction of the Run command at start depending on parameter
settings and rotor position.
• The amount of generated starting torque differs depending on the control mode and motor type. Set up the motor with the
drive after verifying the starting torque, allowable load characteristics, impact load tolerance, and speed control range.
Contact Yaskawa or a Yaskawa agent when planning to use a motor that does not fall within these specifications:
• In Open Loop Vector Control for PM motors, braking torque is less than 125% when running between 20% and 100% speed.
Braking torque drops to less than 50% when running at less than 20% speed.
• In Open Loop Vector Control for PM motors, the allowable load inertia moment is approximately 50 times higher than the
motor inertia moment.
Contact Yaskawa or a Yaskawa agent for questions concerning applications with a larger inertia moment.
• To restart a coasting motor rotating below 100 Hz, use the Speed Search function if the motor cable is not too long. If the
motor cable is relatively long, stop the motor using Short Circuit Braking.
i.2 General Safety
18 YASKAWA ELECTRIC TOEP YAIZ1U 03A YASKAWA AC Drive – Z1000 User Manual