SS1-r (Safe Stop 1)

SS1-r description for drive option Functional Safety 3.

Description

SS1-r , when activated, monitors the controlled stop of the axis until the STO function can be activated. SS1 Instance 1 can be configured as the fault reaction for safety functions SS2, SSR, SDI, SLA, SAR, SLI, SLP and SLS.

During the process, the SS1-r function monitors the velocity. If the velocity stays in the range (n_Zero_SS1) within the time (t_L_SS1) STO activates in advance. In any case, STO activates as soon as the timer (t_SS1) elapsed.

Optionally, SS1-r can monitor the ramp of the controlled stop. The parameter a_SS1 defines the deceleration limit that the axis is not allowed to pass. The parameter t_D_SS1 is used to delay the start of the deceleration monitoring after the SS1 function activated.

Number of Instances

Three instances per axis.

Function Input / Output Variables

Inputs

SS1 Activate can be triggered by
FSoE,
a fault reaction,
I/O failure (instance 1 only) or
safe digital inputs (must be mapped).
STO Activate is triggered by SS1.

Outputs

SS1 Active: logical status of the SS1 function
STO Active: logical status of the STO function

Activation

To activate SS1-r, Velocity & Deceleration Monitoring must be enabled in the safety parameters. If not, SS1-t is used.

The safety function can be mapped with WorkBench or by using FSoE to the safe digital inputs or other functions.

If SS1_2 or SS1_3 is set to “Not Used”, the corresponding FSoE activation bit is ignored even if SAFEFIELDBUS.ACTIVATION is 1 (➜ # 1, SAFEPARAM.SAFEFIELDBUS.ACTIVATION).

Activation by FSoE	For a drive profile overview, see FSoE (➜ # 1, FSoE). For setup and handling, see the AKD2G EtherCAT Manual.
Activation by safe digital inputs	To review the enclosure and wiring instructions, see Enclosure, wiring (➜ # 1, Enclosure, wiring). To see technical data for the safe inputs, see Technical Data (➜ # 1, Technical Data). For notes on activation by safe inputs, see Activation by Safety Digital Inputs (➜ # 1, Activation By Safe Digital Inputs).

Safety Properties

Refer to (➜ # 1, Safety Properties Overview).

Restart

Refer to (➜ # 1, SS1-t (Safe Stop 1)).

Timing

Note:

SS1 is fully completed after activation until STO is activated, even if the request (SS1_Activate) is reset in between.
See limitations for FSoE (➜ # 1, Limitations for SMM1) (➜ # 1, Limitations for SMM2)

Related Parameters

Safety parameters

Name	Variables	Default	Parameter
Function Activation	-	Inst. 1: 1 (Ready for activation) Inst. 2,3: 0 (Never active)	(➜ # 1, AXIS#.SAFEPARAM.SS1_#.FUNCTIONACTIVATION)
Safe Input	-	0 (Not used)	(➜ # 1, AXIS#.SAFEPARAM.SS1_#.SAFEINPUT)
FSoE	-	0 (Not used)	(➜ # 1, AXIS#.SAFEPARAM.SS1_#.FSOE)
Time To STO	t_SS1	2 ms	(➜ # 1, AXIS#.SAFEPARAM.SS1_#.TIMETOSTO)
Velocity & Deceleration Monitoring	-	0 (Disabled)	(➜ # 1, AXIS#.SAFEPARAM.SS1_#.VELDECMONITOREN)
Velocity Zero Window	n_Zero_SS1	1	(➜ # 1, AXIS#.SAFEPARAM.SS1_#.VELZEROWINDOW)
Time For Velocity Zero	t_L_SS1	1 ms	(➜ # 1, AXIS#.SAFEPARAM.SS1_#.TIMEFORVELZERO)
Deceleration Limit	a_SS1	0	(➜ # 1, AXIS#.SAFEPARAM.SS1_#.DECLIMIT)
Time Delay Deceleration Monitoring	t_D_SS1	1 ms	(➜ # 1, AXIS#.SAFEPARAM.SS1_#.TIMEDELAYDECMONITORING)

Diagnostic Parameters

Name	Variables	Default	Parameter
Function Active Status	-	-	(➜ # 1, AXIS#.SAFE.SS1_#.ACTIVE)
Function Internal Status	-	-	(➜ # 1, AXIS#.SAFE.SS1_#.INTERNALSTATE)

Device Parameters

Name	Variables	Default	Parameter
Deceleration Mode	-	0 (Drive driven)	(➜ # 1, AXIS#.SAFE.SS1_#.MODE)
Deceleration Ramp	-	9999.946 rpm/s	(➜ # 1, AXIS#.SAFE.SS1_#.DEC)

State diagram

SS1-r is active when its internal state is in the composite state "Deceleration Monitoring" or "Delay Before Ramp Monitoring (1)".

Setup in WorkBench

Select the drive and open the Safety Parameterization view (➜ # 1, Parameters Editor).

Choose the Axis.
Select the Category.
Select the SS1 function.
Select the Instance number.
Enable Velocity & Deceleration Monitoring to activate SS1-r.

If one dual input (e.g. SIN1/SIN2) activates SS1-r for both axis 1 and axis 2, then set the Activation parameter for both axes to the same input (e.g. Safe Dual Input 1).

Fault Reaction / Failure Message

If dual channel mode is selected, the AKD2G observes to see if the two inputs are in a different state for more than 100 ms. If the two inputs are in different states for more than 100 ms, an I/O failure activates SS1_1 and then the axis is switched off by STO. An I/O failure warning is displayed.

SS1 Instance 1 can be configured as the fault reaction for other safety functions. Functions which support this feature include: SS2, SSR, SDI, SLA, SAR, SLI, SLP and SLS.

Safety State / Status Signals

The signal AXIS#.SAFE.SS1_#.ACTIVE (➜ # 1, AXIS#.SAFE.SS1_#.ACTIVE) can be monitored by safe digital outputs with OSSD pulses (➜ # 1, OSSD). The status signal must be mapped to the safe digital output. Two outputs can be combined to a dual channel output. For parameter descriptions see (➜ # 1, Functional Safety Parameter Reference).