Stop-On-Contact, Load Torque High-Speed Frequency Selection (Pr. 270) - Mitsubishi FR-A500 Series Instruction Manual

Note: 1. This function is invalid when the automatic restart after instantaneous power failure function is
activated.
2. If (output frequency at occurrence of undervoltage or power failure) minus (frequency set in
Pr. 263) is negative, the calculation result is regarded as 0Hz.
3. The power failure stop function is not activated during a stop or error.
4. If power is restored during deceleration, the inverter is kept decelerating to a stop.
To restart, switch off the start signal once, then switch it on again.
5. When the high power factor converter is used (Pr. 30 = 2), this function is made invalid.
If power-failure deceleration operation is set, some loads may cause the inverter to trip
and the motor to coast.
If enough regenerative energy is not given by the motor, the motor will coast.
4.2.60 Stop-on-contact, load torque high-speed frequency selection
(Pr. 270)
Pr. 270 "stop-on-contact/load torque
high-speed control selection"
To ensure accurate positioning at the upper limit etc of a lift, stop-on-contact control causes a mechanical
brake to be closed while the motor is developing a holding torque to keep the load in contact with a
mechanical stopper etc.
This function suppresses vibration which is liable to occur when the load is stopped upon contact in vertical
motion applications, ensuring steady precise positioning.
Load torque high-speed frequency control automatically sets the maximum operating frequency according to
the load.
Specifically, the weight of the load is determined after a start by the average current at a given time; when the
load is light, the preset frequency can be increased for operation.
When the load is light, speed can be automatically increased in a sky parking lot, for example, to reduce
incoming and outgoing times.
! Using Pr. 270, select stop-on-contact control and/or high-speed frequency control (control which
automatically switches between high- and middle-speed operations according to load torque).
• When stop-on-contact control is selected, select advanced magnetic flux vector control. For function
details, refer to Pr. 275 and Pr. 276.
• For function details of load torque high-speed frequency control, refer to Pr. 271 to Pr. 274.
Parameter Factory
Number Setting
270 0
CAUTION
Setting
Range
0 Without stop-on-contact control and load torque high-speed frequency control
1 Stop-on-contact control
2 Load torque high-speed frequency control
3 Stop-on-contact control and load torque high-speed frequency control
161
PARAMETERS
Related parameters
Pr. 271 "high-speed setting maximum
current"
Pr. 272 "mid-speed setting minimum
current"
Pr. 273 "current averaging range"
Pr. 274 "current averaging filter
constant"
Pr. 275 "stop-on-contact exciting current
low-speed multiplying factor"
Pr. 276 "stop-on-contact PWM carrier
frequency"
Description
4