Start, Stop And Fault Reactions; Normal Start; Normal Stop; Emergency Off/Emergency Stop - ABB DCS 600 Manual

3.3 Start, Stop and Fault Reactions

During operation, the drive is in one of the
following states (ABB Drive profile):
After emergency stop
(OFF3_N) or emergency off
ONINHIBIT
(OFF2_N) this state is
entered until ON = 0
Main contactor is off, OFF3_N
OFF
or OFF2_N active
RDY_ON Main contactor is off
Main, field and fan contactor
are closed, field control
RDY_RUN
activated, ready for run
command
RDY_REF Drive is running
TRIPPED Drive is faulted
Drive is coasting due to
emergency off command; the
OFF_2_STA
states ZERO_A_AND_F →
ONINHIBIT are entered.
Drive stops according to the
programmed emergency stop
ramp and the programmed
OFF_3_STA
emergency stop mode; at
zero speed, the state
ON_INHIBIT is entered.
Table 3.1/1: States of the drive
Power up
When the electronics power supply is switched
on the drive stays in the ONINHIBIT state until
ON = 0 is detected. In case of a fault the drive
stays in the FAULT state.

Normal start

Status bit RDY_ON = 1 signals that no faults are
pending and that the device is ready to close the
fan and field contactor.
A rising edge of the ON command closes fan, field
and main contactor and activates the field con-
trol.
Status bit RDY_RUN = 1 indicates that the field
converter is active and that the drive is ready to
generate torque.
A rising edge of the RUN command activates
speed and torque control.
Status bit RUNNING = 1 indicates that the drive is
in normal operation.
II F 3-2

Normal stop

RUN = 0 sets the speed reference to zero and the
drive decelerates.
After the actual speed has reached zero the status
bit RUNNING is reset, the armature converter set
to alpha_max and the state RDY_RUN is entered,
when the current has reached zero.
ON = 0 sets RDY_RUN = 0 and the field current
reference to zero. The field converter is set to
alpha_max and the contactors are opened, when
the current has reached zero.
ON = 0 internally forces RUN = 0.
Emergency off
Field and armature current are removed as fast as
possible. Then the contactors are opened. The
normal start command is accepted when OFF2(_N)
(EME_OFF_N) = 1.
Emergency stop
Command EME_STOP = 0 gives the same proce-
dure as RUN = 0 (normal stop) except that the
ramp is switched from deceleration to emergency
stop and the state ON_INHIBIT is entered when
the speed has reached zero.
The normal start command is accepted when
OFF3(_N) (EME_STOP_N) = 1.
The reference handling and current limitation is
controlled by EME_STOP_MODE.
Fault reaction
Depending on the actual fault the armature and
or field current is reduced to zero as fast as
possible with single pulses and firing angle =
alpha_max. Contactors are opened when the
current has reached zero.
Then the state TRIPPED is entered and after a
successful reset the state ONINHIBIT.
The following state diagram shows the transitions
between the different states.