8
05.01
8.5 Start inhibit in the drive modules/safe standstill
8-254
©
Siemens AG 2012 All Rights Reserved
SIMODRIVE 611 Configuration Manual (PJU) – 02/2012 Edition
When the start inhibit circuit is activated, it is no longer possible to gate several
power transistors orientated to the rotating field.
!
Warning
In the case that two faults simultaneously occur in the power module, a residual
risk remains where the drive suddenly rotates through a small angle:
––> FT motors: 4 pole 90
, 6 pole 60
, 8 pole 45
;
––> Induction motors: In the retentive area, max. 1 slot division,
that corresponds to approx. 5
to 15
When a fault occurs, 1FN linear motors can continue to rotate electrically
through 180
(approx. 56 or 72 mm including overshoot).
!
Warning
When the start inhibit is active, the motor can no longer generate any torque. If
external forces act on the drive axes, additional holding devices and equipment
are required, e.g. brakes. Here, it is especially important to note the effect of
gravity on hanging/suspended axes.
The start inhibit does not result in electrical isolation. This means that under no
circumstances does it provide protection against ”electric shock”.
For operational interruptions, maintenance, servicing and cleaning work
performed on the machine or plant, the complete machine must also be
electrically isolated from the line supply using the line supply isolating device,
e.g. main switch (see EN 60204–1; 5.3).
8.5.3
Connecting–up the start inhibit
The start inhibit is addressed in the drive modules via terminal 663. The start
inhibit relay is controlled using the internal enable voltage FR+ (terminal 9,
+24 V)/or an ex24 V voltage. When using an external voltage source, its
reference potential (ground) must be connected to FR– (terminal 19).
When the relay is open, terminal 663 open, the start inhibit is activated.
When the AS1/AS2 signaling contact is closed, this signals the ”start inhibit is
effective” state with electrical isolation.
The circuit must be protected against overload and short circuit using a fuse
with a max. 2 A rating!
When terminal 663 is externally controlled (drive), a fail–safe signal must be
used.
8 Important Circuit Information
02.03