Mitsubishi Electric FR-A740-00023 Instruction Manual page 220

Motor brake and stop operation
(4) Protective functions
If any of the following errors occurs in the brake sequence mode, the inverter results in an alarm, shuts off the output,
and turns off the brake opening request signal (BOF).
Error Display
(Detection frequency) - (output frequency) > Pr. 285 during encoder feedback control
E.MB1
When Pr. 285 Overspeed detection frequency = 9999, overspeed is not detected.
Deceleration is not normal during deceleration operation from the set frequency to the frequency set in
E.MB2
Pr. 282. (when Pr. 284 =1) (except stall prevention operation)
E.MB3 Brake opening request signal (BOF) turned on though the motor is at a stop. (gravity drop prevention function)
Although more than 2s have elapsed after the start command (forward or reverse rotation) is input, the brake
E.MB4
opening request signal (BOF) does not turn on.
Although more than 2s have elapsed after the brake opening request signal (BOF) turned on, the brake opening
E.MB5
completion signal (BRI) does not turn on.
Though the inverter had turned on the brake opening request signal (BOF), the brake opening completion signal
E.MB6
(BRI) turned off midway.
Although more than 2s have elapsed after the brake opening request signal (BOF) turned off at a stop, the brake
E.MB7
opening completion signal (BRI) does not turn off.
CAUTION
⋅ Overspeed detection (Pr. 285) is valid under encoder feedback control (used with the FR-A7AP option) even if a value other than
"7 or 8" is set in Pr. 292.
⋅ A too large setting of Pr. 278 Brake opening frequency activates stall prevention operation and may cause E.MB4.
♦ Parameters referred to ♦
Pr. 80 Motor capacity, Pr. 81 Number of motor poles
Pr. 180 to Pr. 186 (input terminal function selection)
Pr. 190 to Pr. 195 (output terminal function selection)
Pr. 800 Control method selection
Encoder feedback control
210
Refer to page 87
Refer to page 222
Refer to page 230
Refer to page 87
Refer to page 367
Description