Operation principle
1. The Safe torque off activates (the activation switch is opened, or safety relay contacts
open).
2. The STO inputs of the drive control unit de-energize.
3. The control unit cuts off the control voltage from the output IGBTs.
4. The control program generates an indication as defined by parameter
31.22
(see
the firmware manual of the drive).
The parameter selects which indications are given when one or both STO signals
are switched off or lost. The indications also depend on whether the drive is running
or stopped when this occurs.
Note:
This parameter does not affect the operation of the STO function itself. The
STO function will operate regardless of the setting of this parameter: a running drive
will stop upon removal of one or both STO signals, and will not start until both STO
signals are restored and all faults reset.
Note:
The loss of only one STO signal always generates a fault as it is interpreted
as a malfunction of STO hardware or wiring.
5. The motor coasts to a stop (if running). The drive cannot restart while the activation
switch or safety relay contacts are open. After the contacts close, a reset may be
needed (depending on the setting of parameter
31.22
). A new start command is
required to start the drive.
The Safe torque off function 215
Summary of Contents for ACS880-11
Page 1: ... ABB INDUSTRIAL DRIVES ACS880 11 drives Hardware manual ...
Page 2: ......
Page 4: ......
Page 26: ...26 ...
Page 52: ...52 ...
Page 82: ...82 ...
Page 95: ...R6 R8 IP21 R6 R8 IP55 Electrical installation IEC 95 ...
Page 103: ...R6 1 5 N m 0 5 N m Electrical installation IEC 103 ...
Page 104: ...R8 1 5 N m 0 5 0 6 N m 104 Electrical installation IEC ...
Page 116: ...R6 R8 UL Type 1 R6 R8 UL Type 12 116 Electrical installation North America NEC ...
Page 142: ...142 ...
Page 154: ... Fan arrow must point up 154 Maintenance ...
Page 160: ...160 ...
Page 181: ... Package dimensions R6 R3 R8 Technical data 181 ...
Page 202: ...R3 IP21 UL Type 1 3AXD50000045323 202 Dimension drawings ...
Page 203: ...R3 Option B056 IP55 UL Type 12 3AXD50000045322 Dimension drawings 203 ...
Page 204: ...R6 IP21 UL Type 1 3AXD50000045353 204 Dimension drawings ...
Page 205: ...R6 Option B056 IP55 UL Type 12 3AXD50000045352 Dimension drawings 205 ...
Page 206: ...R8 IP21 UL Type 1 3AXD50000047667 206 Dimension drawings ...
Page 207: ...R8 Option B056 IP55 UL Type 12 3AXD50000047667 Dimension drawings 207 ...
Page 208: ...208 ...
Page 225: ... Declarations of conformity The Safe torque off function 225 ...