n L1-02: Motor Overload Protection TimeSets the detection time of motor overheat due to overload. This setting rarely requires adjustment, but should correlate withthe motor maximum load current protection time for performing a hot start.No. Name Setting Range DefaultL1-02 Motor Overload Protection Time 0.1 to 50.0 minutes 1.0 minuteDefaulted to operate with an allowance of 150% overload operation for one minute in a hot start.Figure 5.42 illustrates an example of the electrothermal protection operation time using a general-purpose motor operating atthe value of E1-06, Motor Base Speed, with L1-02 set to one minute.During normal operation, motor overload protection operates in the area between a cold start and a hot start.• Cold start: Motor protection operation time in response to an overload situation that was suddenly reached when starting astationary motor.• Hot start: Motor protection operation time in response to an overload situation that occurred during sustained operation atrated current.Operation time (minutes)Cold startHot startMotor current (%)E2-01 = 100% motor current107310.40.10 100 150 200Figure 5.42 Motor Protection Operation Timeu L2: Momentary Power Loss Ride-Thrun L2-01: Momentary Power Loss Operation SelectionWhen a momentary power loss occurs (DC bus voltage falls below the level set in L2-05), the drive can automatically returnto the operation it was performing prior to the power loss based on certain conditions.Note: Default is 2 in bypass controller software versions VST800298 and later. Default is 0 in bypass controller software versions VST800297and earlier.No. Name Setting Range DefaultL2-01 Momentary Power Loss Operation Selection 0 to 2 2Setting 0: DisabledIf power is not restored within 15 ms, a Uv1 fault will result and the motor coasts to stop.Setting 1: Recover within L2-02When a momentary power loss occurs, the drive output will be shut off. If the power returns within the time set to parameterL2-02, the drive will perform Speed Search and attempt to resume operation. If the power does not return within this time, itwill trigger a Uv1 fault.Note: L2-02 value is dependent on drive model selection and is not accessible.Setting 2: Recover as long as CPU Has PowerWhen a momentary power loss occurs, the drive output will be shut off. If the power returns and the drive control circuit haspower, the drive will attempt to perform Speed Search and resume the operation. This will not trigger a Uv1 fault.Notes on Settings 1 and 2“Uv” will flash on the operator while the drive is attempting to recover from a momentary power loss. A fault signal is notoutput at this time.5.9 L: Protection FunctionsYASKAWA ELECTRIC SIEP YAIZ1B 01E YASKAWA AC Drive – Z1000 Bypass Technical Manual 1695 Programming
