Yaskawa Z1000U HVAC Matrix Bypass - Manual (Page 51)

Acceleration/Deceleration Times
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 as
long as the Stall Prevention function is in operation. Install one of the available braking options or increase the capacity of the
drive for faster acceleration and deceleration.
n General Handling
Wiring Check
NOTICE: Do not connect power supply lines to output terminals U/T1, V/T2, or W/T3. Failure to comply will destroy the drive. Be sure to
perform a final check of all sequence wiring and other connections before turning on the power and also check for short circuits on the
control terminals, which may damage the drive.
Inspection and Maintenance
WARNING! Electrical Shock Hazard. Capacitors in the drive do not immediately discharge after shutting off the power. Wait for at least the
amount of time specified on the drive before touching any components after shutting off the power. Failure to comply may cause injury to
personnel from electrical shock.
Transporting the Drive
NOTICE: Never steam clean the drive. During transport, keep the drive from coming into contact with salts, fluorine, bromine, phthalate
ester, and other such harmful chemicals.
u Motor Application Precautions
Insulation Tolerance
NOTICE: Consider motor voltage tolerance levels and motor insulation in applications with an input voltage of over 480 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 isolation mounts around the base of the motor and enable the Jump
frequency selection to prevent continuous operation in the resonant frequency range.
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 Specialized Motors
Multi-Pole Motor
The rated current of a multi-pole motor differs from that of a standard motor, so be sure to check the maximum current when
selecting a drive. Always stop the motor before switching between the number of motor poles. The motor will coast to stop if
a regen overvoltage (ov) fault occurs or if overcurrent (oC) protection is triggered.
Submersible Motor
The rated current of a submersible motor is greater than that of a standard motor, so select the drive accordingly. Use a motor
cable large enough to avoid decreasing the maximum torque level from voltage drop caused by a long motor cable.
Explosion-Proof Motor
The motor and the drive must be tested together to be certified as explosion-proof. The drive is not designed for explosion-
proof areas.
i.2 General Safety
YASKAWA SIEP YAIZ1D 01A Z1000U HVAC MATRIX Drive Bypass Technical Manual 51