Siemens SIMODRIVE 611 Planning Manual page 278

9 Important Circuit Information
9.7 Circuit examples =1 to =10 with SIMODRIVE 611 analog
9
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Speed monitoring
Setting–up operation
When the automatic mode is cancelled, contactor =5–K15 de–energized or the
protective door released or opened, contactor =6–K11 is de–energized, terminal
69–70 opened, and the speed is monitored for standstill. When enabled via
pushbutton =5–S11, contactors =5–K13/=5–K14 are energized and the speed,
set at the monitoring device, for setting–up operation, monitored.
When the permissible speed is exceeded, contacts –A11/79–80 and –
A11/75–76 open. The pulses for the spindle drive are inhibited, and at the same
time the emergency stop function is initiated via contactor =4–K21 and the
drives are shut down.
Automatic operation
When the max. permissible speed, set at the selector switch (the reduction is
programmed as a %) is exceeded, the drives are also immediately shutdown as
described before. The device should be adapted to the speed and pulse fre-
quency of the speed encoder via the speed programming inputs.
Depending on the hazard analysis, it may be necessary to use speed monito-
ring, e.g. also for the feed drives and/or also for the user–side machine func-
tions. The control must be appropriately adapted on the user side.
Circuit example =8 "Limit switch end position
monitoring"
Application/functions
Normally, the end position of the axis traversing range in the machine is monito-
red using software limit switches which become active after the reference point
approach. If, under a fault condition, a software limit switch is passed, and the-
refore a hardware limit switch actuated, contactor =4–K21 is de–energized via
the interlocking circuit terminals 81–82 in the EMERGENCY STOP circuit. The
drives are braked along the current limit and are then shutdown.
However, an axis can only be effectively braked if there is an appropriate di-
stance between the hardware limit switch and the mechanical end stop of the
axis to take into account brake travel.
The actuated end position limit switches can be disabled via the PLC inputs. In
the setting–up mode, the axis can move away from the end position using key–
actuated switch –S13 and be moved away in the opposite direction using push-
button =5–S11, enabling.
 Siemens AG 2001 All rights reserved
SIMODRIVE 611 Planning Guide (PJU) – 05.01 Edition
05.01