Hitachi WJ Series User Manual page 294

Chapter 9
Output frequency
DC braking
RUN command
Brake release
[BRK] output
Answer back from Brake
[BOK] input
Brake confirmation signal wait time [b124]
(1) When the RUN command is received, the inverter accelerates to the "Creep speed [P015]".
The rotation direction is forward rotation if (current position - target position) is positive, and
reverse rotation if (current position - target position) is negative.
If the target position is within ± "Positioning completed range [P017]", it stops on the spot without
releasing the brake. Whether the DC braking is performed depends on the setting of [b120].
(2) After the output frequency reaches "Creep speed [P015]" and after "Brake release wait time [b121]"
has elapsed, "Brake release [BRK] (19)" is turned on.
However, if the output current at this time is less than "Brake release current [b126]", [BRK] is not
turned on, and instead, the "Brake error [E36]" trip occurs and "Brake error [BER] (20)" is turned on.
(3) Operation differs depending on whether or not "Answer back from brake [BOK] (44)" is assigned to
the input terminal.
With [BOK] assignment:
Without [BOK] assignment: After [BRK] is turned on, move to step (4).
(4) After the [BOK] input is turned on (or after the [BRK] output is turned on), when "Brake wait time for
accel. [b122]" has elapsed, it accelerates to the set frequency again. If the amount of movement to
the target position is small, deceleration starts before reaching to the set frequency.
(5) Deceleration starts before the target position (before "the amount of movement during
deceleration" + "Position displacement at creep speed [P014]"). The inverter decelerates to "Creep
speed [P015]" and [BRK] is turned off.
(6) Operation differs depending on whether or not "Answer back from brake [BOK] (44)" is assigned to
the input terminal.
With [BOK] assignment:
Without [BOK] assignment: After [BRK] is turned off, move to step (7).
(7) After the [BOK] input is turned off (or the [BRK] output is turned off), it decelerates to 0 Hz again
after "Brake wait time for stopping [b123]" or the moving time of "Position displacement at creep
speed [P014]", whichever is longer.
(8) After stopping, the inverter follows the setting of "Brake control enable [b120]". When "Enable (DC
braking enabled at stop when position control is enabled) (01)" is selected, the DC braking is
activated, and the output is shut off when the RUN command is turned off. When "Enable (DC
braking disabled at stop when position control is enabled) (02)" is selected, the output is shut off.
Creep speed [P015]
(1)
(4)
Brake wait time
for accel. [b122]
(2)
Brake release wait time [b121]
(3)
After [BRK] is turned on, the inverter waits for [BOK] to be turned on
during the "Brake confirmation signal wait time [b124]" without
accelerating. If [BOK] is not turned on within the wait time, the "Brake
error [E36]" trip occurs and "Brake error [BER] (20)" is turned on.
After [BRK] is turned off, the inverter waits for [BOK] to be turned off
during "Brake confirmation signal wait time [b124]" without
decelerating. If [BOK] is not turned off within the wait time, the "Brake
error [E36]" trip occurs and "Brake error [BER]" is turned on.
9-14-14
Inverter Functions
Creep speed [P015]
Position displacement at
creep speed [P014]
Brake wait time for
(5)
(7)
stopping [b123]
(8)
(6)
Brake confirmation signal wait time [b124]