Using One Drive With Multiple Motors; Wiring Length Greater Than 50 Meters (164 Feet); Voltage Boost And High Torque V/F Pattern Settings - YASKAWA V1000 Series Installation & Start-Up Manual

7.4 Installing Peripheral Devices
UL recognized electronic thermal overload function of the drive: Speed-dependent
heat characteristics are simulated using data from standard motors and force-ventilated
motors. The motor is protected from overload using this function.

Using One Drive with Multiple Motors

Turn off the electronic thermal overload function. Please refer to the appropriate product
instruction manual to determine which parameter disables this function.
The UL recognized electronic thermal overload function of the drive cannot be applied
when using multiple motors on one drive. The electronic thermal function is calculated
using the output current of the drive. Individual motor currents cannot be determined
using the output current of the drive. Therefore, a thermal relay is required for each
motor connected to the drive.

Wiring Length Greater Than 50 meters (164 feet)

When motor wiring is longer than 164 feet (50 meters), nuisance tripping of the thermal
relaymay occur if a high carrier frequency is used. Due to increased high frequency leakage
current the thermal relay element may overheat due to surface skin effect. Therefore, reduce
the carrier frequency.
The following should be considered for long motor cable length applications:
1. For a single motor drive, use the electronic thermal overload function of the drive (thermal
relay not required).
2. For multiple motor drives:
Lower the carrier frequency according to
relay adjustment according the
Figure 7.15

Voltage Boost and High Torque V/f Pattern Settings

The V/f pattern and voltage boost settings may impact motor heating. Improperly adjusted
V/f patterns or torque compensation settings may cause over-excitation of the motor,
282
Table
Figure 7.15 Criteria for Setting Carrier Frequency
YASKAWA ELECTRIC TOEP C710606 09B YASKAWA AC Drive V1000 Installation & Start-Up Manual
Figure 7.15 or correct the motor thermal OL
7.3.