Safe Stop 2 (Ss2) - Lenze i950 Commissioning Manual

Safety functions

Safe Stop 2 (SS2)

19.5 Safe Stop 2 (SS2)
The safety function monitors whether the drive has reached the set tolerance window (n = 0)
within the parameterised stopping time.
After the stopping time has elapsed or the value has fallen below the tolerance window, the
monitoring function switches to safe operational stop (SOS) or activates the safety function
(STO).
In the safe operational stop, the drive is not switched to torque-free operation. All control
functions remain active for maintaining the reached position.
WARNING!
A safety-rated encoder system must be used.
Without an encoder, this safety function cannot be used.
▶ Apply a safety-rated encoder system to use this function.
Preconditions
The drive is brought to standstill via the application.
Movements caused by external forces require additional measures. When the stopping time is
defined, the application time of the brake must be taken into consideration.
The restart is possible after the stopping time has completely elapsed. An exception from this
is the special operation.
Functional description
The deceleration ramp can be parameterised and monitored for the stop func-
tion SS2.
SS2-t
0x289B:001 = 0 (SOS after stopping time)
SS2
n
0x2894:001
b
a
0
0x287B:001
The safe operational stop Safe Operating Stop (SOS)
stopping time parameterised in 0x2894:0010x2894:001 (stopping time
for SS1 and SS2) has elapsed and the motor speed is lower than the
value parameterised in 0x287B:0010x287B:001, tolerance window
Curve (a): for details see Safe Operating Stop
Curve (b): STO is also activated if, after the stopping time
0x2894:0010x2894:001, stopping time for SS1 and SS2 has elapsed,
speed is not lower than the value parameterised in
001, tolerance window (n=0).
Via a safe input, if the corresponding parameter is assigned to the safe input.
Activation of the function
A data telegram is sent to the inverter via the safety bus. See chapter
ces".
^ 417
In response to the error stop request.
382
SS2-t
0x289B:001
SOS
STO
t
is activated if the Curve (a): for details see
(n=0).
(SOS). . Curve (b): STO is also activated if, after the stopping time
^ 385
0x2894:0010x2894:001, stopping time for SS1 and SS2 has elapsed,
speed is not lower than the value parameterised in
001, tolerance window
the
0x287B:0010x287B:
= 1 (SOS at n = 0)
SS2
n
0x2894:001
b
SOS
a
STO
0
0x287B:001
Safe Operating Stop (SOS).
(n=0).
"Safe network interfa-
t
.
^ 385
the
0x287B:0010x287B: