Mitsubishi Electric FR-A700 Series, Technical Manual

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4
P
RACTICAL CIRC
UI
T
S
PRACTICAL CIRCUITS
4.9.2 Use of brake sequence circuit function
(A700)
• At start: When the start signal is input to the inverter, the output is provided at the starting frequency, and when the
given frequency [
Pr. 278 ] is reached and the output current exceeds the current set in [ Pr. 279 ], the brake
opening request signal BOF is output.
When the given time set in [
Pr. 281 ] has elapsed after the brake opening completion signal BRI has been input,
the output frequency is raised to the preset speed.
• At stop: When the speed is reduced to the brake operation frequency [ Pr. 282 ], the brake opening request signal BOF is
turned OFF. When the given time set in [ Pr. 283 ] has elapsed after the brake opening completion signal BRI
had been turned OFF, the output frequency is switched OFF.
*1 When the motor equipped with a brake is run at or less than 30Hz continuously, the brake disc may rattle but the
motor may be used without any problem if it is run at low speed for a short period, e.g. in orientation. Also, as there
is a limit to the braking capacity, run the motor at no more than 60Hz.
*2 When the power supply is 400V class, install a step-down transformer.
A700 E700
U
V
W
R
S
T
Earth (Ground)
Inverter
MCCB
Power
supply
T
F
Motor
BR
B
MC
Brake
IM
MC
C
B
RA
+24 V 0V
BOF
SD
BR
STF
STR
RH
RL
RES
SD
Related parameters
[ Pr.292 ]
Brake opening frequency [ Pr.278 ]
[ Pr.279 ]
[ Pr.280 ]
[ Pr.281 ]
[ Pr.282 ]
[ Pr.283 ]
[ Pr.284 ]
*2
BRI
[ Pr.285 ]
Ready
"OFF"
PB
"ON"
PB
Forward rotation
Reverse rotation
High speed
Low speed
Brake operation signal
Reset
24VDC
power supply
Automatic acceleration/deceleration
Brake opening current
Brake opening current detection time
Brake operation time at a start
Brake operation frequency
Brake operation time at stop
Deceleration detection function selection
Overspeed detection frequency
M
C
B
R R
A