Mitsubishi Electric FR-A800, Instruction Manual

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(A) Application parameters Parameters
5 - 486
Setting the brake sequence operation
●
Set Pr. 292 = "7 or 8 (braking sequence operation)".
To ensure sequence operation, it is recommended to use with Pr. 292 = "7" (with brake opening
completion signal input).
●
Set "15" in any of Pr. 178 to Pr. 189 (input terminal function selection), and assign the brake opening
completion signal (BRI) to the input terminal.
●
Set "20" (positive logic) or "120" (negative logic) in any of Pr. 190 to Pr. 196 (output terminal
function selection), and assign the brake opening request signal (BOF) to the output terminal.
●
Use Pr. 639 "Brake opening current selection" to select whether the output current or the motor
torque is used as a reference for the brake opening operation. (Under V/F control, the output
current is used as a reference regardless of the Pr.639 setting.)
●
Under Real sensorless vector control, vector control, or PM sensorless vector control, use Pr. 640
"Brake operation frequency selection" to select whether the frequency command or the actual
motor speed (estimated value) is used as a reference for brake closing operation.
If the brake operation timing is different from the motor speed because of the load, set Pr. 640 =
"1 (brake operation with the actual motor speed (estimated value))".
●
Under V/F control or Advanced magnetic flux vector control, perform brake operation while
referring to the frequency command regardless of the Pr. 640 setting.
Operation with brake opening completion signal input (Pr. 292 = "7")
●
When the start signal is input to the inverter, the inverter starts running, and when the output
frequency reaches the frequency set in Pr. 278 "Brake opening frequency" and the output current
or the motor torque is equal to or greater than the Pr. 279 "Brake opening current" setting, the
brake opening request signal (BOF) is output after the time set in Pr. 280 "Brake opening current
detection time".
The brake opening completion signal (BRI) is input, and the output frequency is increased to the
set speed after the set time in Pr. 281 "Brake operation time at start".
●
When the inverter decelerates to the frequency set in Pr. 282 "Brake operation frequency" during
deceleration, the inverter turns OFF the BOF signal and decelerates further to the frequency set
in Pr. 278. After electromagnetic brake operation completes and the inverter recognizes the turn
OFF of the BRI signal, the inverter holds the frequency set in Pr. 278 for the time set in Pr. 283 "Brake
operation time at stop". And after the time set in Pr. 283 passes, the inverter decelerates again. The
inverter outputs is shut off when the frequency reaches Pr. 13 "Starting frequency" setting or
0.5 Hz, whichever is lower.
NOTE Under torque control, position control, or PM sensorless vector control (with the low-speed range
high torque characteristic disabled), the brake sequence function is disabled.