Mitsubishi Electric FR-A800, Instruction Manual

Page: 669 / 1042

Parameters (A) Application parameters
FR-A800 5 - 489
5.14.4 Stop-on-contact control
To ensure accurate positioning at the upper limit, etc. of a lift, stop-on-contact control causes the me-
chanical brake to close while the motor creates a holding torque to keep the load in contact with a me-
chanical stopper, etc.
This function suppresses vibration that is likely to occur when the load is stopped upon contact in lift
applications, thereby ensuring reliable and highly accurate positioning stop.
NOTES During PM sensorless vector control, the brake sequence function is available with the IPM motor
MM-CF only.
During deceleration, inverter output is shut OFF when the frequency reaches Pr. 13 "Starting fre-
quency" or 0.5 Hz, whichever is lower. For Pr. 278 "Brake opening frequency", set a frequency equal
to or higher than the Pr. 13 setting or 0.5 Hz.
Pr. 285 "Overspeed detection frequency" is valid under encoder feedback control (used with the
FR-A8AP (option)) even if a value other than "7 or 8" is set in Pr. 292 "Automatic acceleration/decel-
eration".
Setting Pr. 278 too high activates the stall prevention and may cause E.MB4.
E.MB4 occurs when the acceleration time from Pr. 13 to Pr. 278 + Pr. 280 reaches or exceeds 2 s.
Parameters referred to
Pr. 3 Base frequency => page 5-654
Pr. 180 to Pr. 186 (input terminal function selection) => page 5-422
Pr. 190 to Pr. 195 (output terminal function selection) => page 5-361
I001567E
Fig. 5-232: Suppressing vibration in vertical motion applications
Less than 2 s
Pr. 280
Pr. 278
Pr. 13
Output
frequency
(Hz)
Time
ON
Brake opening request
(BOF signal)
Ou
tp
ut
fr
e
q
uen
c
y
(Hz)
Magnetic flux Magnetic flux Magnetic flux Sensorless Sensorless Sensorless
Without stop-on-contact control With stop-on-contact control
Lift
Vibration Complete stop
Lift