7.15 Safe Torque Off (STO)
The STO function is defined according to EN 61800-5-2
When activating the STO signal, the motor is disabled and no or no reasonable motor current is driven.
The STO is also possible for non-safe position encoders.
On the drive, there is one instance of STO implemented.
Figure 23: STO Timing
STO can be activated from safe digital inputs or from the safe fieldbus.
On the STO request the brake is immediately activated (if configured). After the time SBC STO_Delay (t1 in figure) STO
becomes active and the motor becomes free of force or torque.
7.15.1 Parameters
STO can be configured with the following parameter:
Name
UPID
Type
Unit
Description
Min
Max
Typical
SBC STO_Delay
(t1 in timing
diagram)
47D5h
UInt16
1 ms
Defines the delay between brake activation and STO.
0 s
60 s
20 ms
Table 66: STO Parameters
If STO shall be requested by a safe digital input, the configuration must be set accordingly, see 7.11.2 - Parameters
If the STO state shall be displayed with the safe digital output, the configuration must be set accordingly, see 7.13.2 -
Parameters
If STO shall be requested via safe fieldbus, the safe fieldbus must be activated, see 7.10.3 - Safe Fieldbus
Configuration.
2S Drive Systems / 0185-1174_E_1V1_SM_C1251-2S / NTI AG
0185-1174_E_1V1_SM_C1251-2S / 2021-11-26 16:43 (Rev. 12500)
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