YASKAWA Varispeed f7

xiv
Adjusting Frequency References ............................................................... 6-35
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Adjusting Analog Frequency References ..................................................................... 6-35
 Operation Avoiding Resonance (Jump Frequency Function)....................................... 6-38
 Adjusting Frequency Reference Using Pulse Train Inputs........................................... 6-40
Speed Limit (Frequency Reference Limit Function) ................................... 6-41
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Limiting Maximum Output Frequency........................................................................... 6-41
 Limiting Minimum Frequency ....................................................................................... 6-41
Improved Operating Efficiency ................................................................... 6-43
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Reducing Motor Speed Fluctuation (Slip Compensation Function) .............................. 6-43
 Compensating for Insufficient Torque at Startup and Low-speed Operation
(Torque Compensation)................................................................................................ 6-45
 Hunting-prevention Function ........................................................................................ 6-47
 Stabilizing Speed (Speed Feedback Detection Function) ............................................ 6-48
Machine Protection .................................................................................... 6-49
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Limiting Motor Torque (Torque Limit Function) ............................................................. 6-49
 Preventing Motor Stalling During Operation ................................................................. 6-52
 Changing Stall Prevention Level during Operation Using an Analog Input .................. 6-53
 Using Frequency Detection .......................................................................................... 6-53
 Detecting Motor Torque ................................................................................................ 6-56
 Changing Overtorque and Undertorque Detection Levels Using an Analog Input ....... 6-59
 Motor Overload Protection ........................................................................................... 6-60
 Setting Motor Protection Operation Time ..................................................................... 6-62
 Motor Overheating Protection Using PTC Thermistor Inputs ....................................... 6-63
 Limiting Motor Rotation Direction ................................................................................. 6-65
Continuing Operation ................................................................................. 6-66
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Restarting Automatically After Power Is Restored........................................................ 6-66
 Speed Search............................................................................................................... 6-67
 Continuing Operation at Constant Speed When Frequency Reference Is Lost ........... 6-74
 Restarting Operation After Transient Fault (Auto Restart Function)............................. 6-74
Inverter Protection...................................................................................... 6-76
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Performing Overheating Protection on Mounted Braking Resistors............................. 6-76
 Reducing Inverter Overheating Pre-Alarm Warning Levels ......................................... 6-77
Input Terminal Functions ............................................................................ 6-78
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Temporarily Switching Operation between Digital Operator and Control Circuit
Terminals ...................................................................................................................... 6-78
 Blocking Inverter Outputs (Baseblock Commands)...................................................... 6-79
 Stopping Acceleration and Deceleration (Acceleration/Deceleration Ramp Hold) ....... 6-80
 Raising and Lowering Frequency References Using Contact Signals (UP/DOWN) .... 6-81
 Accelerating and Decelerating Constant Frequencies in the Analog References
(+/- Speed).................................................................................................................... 6-84
 Hold Analog Frequency Using User-set Timing ........................................................... 6-85
 Switching Operations between a Communications Option Board and Control Circuit
Terminals ...................................................................................................................... 6-85
 Jog Frequency Operation without Forward and Reverse Commands (FJOG/RJOG) . 6-86