Siemens SINUMERIK 840D sl Manual page 219

Drives Start/Stop
The (=4.–K78) Drives Start pushbutton activates the axis-specific controller enables. The
(=4.-S77) Drives Stop pushbutton brings the drives to a standstill. The type of the standstill
action must be defined in the Drive Object of the Control Unit.
Drive group / drives Off
The Emergency Stop (=4.-S73) pushbutton or the Drives / Drive Group Off (=4.-S72)
pushbutton brakes the drives as fast as possible at a set current level (OFF3) of the drive
components to a standstill, provided they have not yet been stopped by the PLC program.
The instantaneous contact of the safety switching device (=4.-K72) on the Control Unit is
used to control the OFF3 switch off command (=4.-K11-X122:2, DI1).
Once the braking action has completed, a time delay (=4.-K71) and a replication block (=4.-
K73) is used to select safety-relevant the "Safe Standstill" function. This is done with the
Control Unit (=4.-K11-X122:3, DI2) and parallel with the associated Motor Module (=4.-Q61,
=5.-Q11, -X21/22:3, EP).
The "Safe Standstill" function must be controlled using safe engineering. Depending on the
requirement in the corresponding categories in accordance with EN 954-1.
The Drives Off (=4.-S72) pushbutton also acts on the PLC -E445. This means PLC logic can
be used to determine which switch-off command caused the drive group to be shutdown.
??The PLC can be used for logical linking, which, independent of the operational state of the
components, drive group can also be switched off by the contactor (=4.–K76)??.
The drives are stopped with emergency stop in the stop category 1 in accordance with EN
60204–1, "Controlled Stopping", the energy supply is interrupted only when the standstill is
achieved.
Holding brake
The holding brake is controlled coordinated using the Motor Module. When the "Safe
Standstill" is selected, the brake is closed immediately. Consequently, the "Safe Standstill"
function should be selected only when the drives have been brought to a standstill.
Otherwise the holding brake can be damaged.
Guide for the SINUMERIK 840D sl machine configuring
Manual, 07/2006 Edition, 6FC5397-6CP10-0BA0
Line Modules and the Motor Modules report ready, the drive axes can be operated with
the corresponding controller enables via PROFIBUS.
Typical circuit diagrams
7.6 Circuit Manual Group =4
7-31