Long Motor Cables
When a high carrier frequency and long motor cables are used, nuisance tripping of the thermal relay may occur due to increased
leakage current. To avoid this, reduce the carrier frequency or increase the tripping level of the thermal overload relay.
Nuisance Tripping Due to a High AC Drive Carrier Frequency
Current waveforms generated by high carrier frequency PWM drives tend to increase the temperature in overload relays. It
may be necessary to increase the trip level setting when encountering nuisance triggering of the relay.
WARNING! Fire Hazard. Confirm an actual motor overload condition is not present prior to increasing the thermal oL trip setting. Check
local electrical codes before making adjustments to motor thermal overload settings. Failure to comply could result in death or serious injury.
6.5 Installing Peripheral Devices
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YASKAWA ELECTRIC TOEP C710616 45F YASKAWA AC Drive – Z1000 User Manual