Stop function STO
Task
- In normal operation, the motor of a machine is monitored for 'SMS safe maximum speed'.
- If the emergency stop push-button on safety input SE3 is pressed, the drive of the machine must be switched torque free immediately.
Safety functions
| Safety input | function |
|---|---|
| SE1 | inactive |
| SE2 | inactive |
| SE3 | STO |
Normal operation:
'Safe maximum speed (SMS)'
Properties
- Special case of the SSR safety function according to DIN EN 61800-5-2:2008-04.
-
Safe 2-channel monitoring of the actual speed value.
Description:
- The SMS safety function is automatically started after the system booting and cannot be deactivated.
-
As soon as the started safety function registers that the limits of the monitored values are exceeded, the drive executes the parameterised save stop function.
- In this application example, 'Safe torque off (STO)' is selected as error reaction
Safe stop function:
'Safe torque off (STO)'
Properties:
-
Safety function acc. to DIN EN 61800-5-2:2008-04.
- Uncontrolled stop according to EN 60204-1, stop category 0.
- The drive is immediately (≤ 10 ms) switched torque-free.
-
Stop functions are prioritised over other safety functions.
Description
-
Safe stop functions are edge-sensitive and cannot be interrupted.
-
Protection against unexpected start of the motor.
Notes on structure and wiring
All established standards and guidelines as well as instructions of the manufacturer of the safety elements must be observed.
Relevant safe parameters
The parameters of the groups 'Safety Settings', Safety IOs' and 'Safe maximum speed (SMS)' are active at any time and cannot be switched off.
| Parameter | Name | Code | Unit | Application-specific settings | |
|---|---|---|---|---|---|
| Value |
SafePMT selection |
||||
| Prm2 | 'Switch-off threshold position' | Pos_Diff | Inkr | 100 | - |
| Prm3 | 'Switch-off threshold velocity' | Vel_Diff | 1/min | 20 | - |
| Prm4 | 'Channel 1 encoder type' | Enc_Ch1 | - | 0 | Resolver |
| Prm5 | 'Channel 2 encoder type' | Enc_Ch2 | - | 0 | Resolver |
| Prm6 | 'Sine encoder period' | Enc_Per | - | 128 | - |
| Prm7 | 'Commanding' | Cmd_Src | - | 1 | inputs SE1..SE3 |
| Prm8 | 'Output control' | Out_Src | - | 1 | system |
| Prm9 | 'Transition time in case of standstill' | T(warn) | min | 360 | - |
| Prm10 | 'Reaction time in case of standstill' | T(err) | min | 120 | - |
| Parameter | Name | Code | Unit | Application-specific settings | |
|---|---|---|---|---|---|
| Value |
SafePMT selection |
||||
| Prm15 | 'SE1 safety function' | SF_SE1 | - | 16 | off |
| Prm16 | 'SE2 safety function' | SF_SE2 | - | 16 | off |
| Prm17 | 'SE3 emergency stop function' | StF_SE3 | - | 0 | STO |
| Prm81 | 'SE3 dynamic sampling' | SE3_DYN | - | 1 | active dynamic sampling |
| Prm82 | 'SE3 input level' | SE3_INV | - | 1 | inverted input level |
| Prm83 | 'SE3.1 dynamic sampling impulse duration' | SE3.1_Puls | μs | 1000 | - |
| Prm84 | 'SE3.1 dynamic sampling period' | SE3.1_Time | ms | 50 | - |
| Prm85 | 'SE3.2 dynamic sampling impulse duration' | SE3.2_Puls | μs | 2000 | - |
| Prm86 | 'SE3.2 dynamic sampling period' | SE3.2_Time | ms | 100 | - |
| Prm99 | 'SDYN1 dynamic sampling impulse duration' | SDYN1_Puls | μs | 1000 | - |
| Prm100 | 'SDYN1 dynamic sampling period' | SDYN1_Time | ms | 50 | - |
| Prm101 | 'SDYN2 dynamic sampling impulse duration' | SDYN2_Puls | μs | 2000 | - |
| Prm102 | 'SDYN2 dynamic sampling period' | SDYN2_Time | ms | 100 | - |
| Parameter | Name | Code | Unit | Application-specific settings | |
|---|---|---|---|---|---|
| Value |
SafePMT selection |
||||
| Prm67 | 'SMS safe maximum speed' | N(max,SMS) | 1/min | 6000 | - |
| Prm68 | 'SMS error reaction' | SMS_ERR | - | 0 | STO |
