This is the web edition of the original ⮫ AC500-S safety user manual, version 1.3.2. This web edition is provided for quick reference only. The original safety user manual must be used to meet functional safety application requirements. |
Standards |
Requirements |
---|---|
IEC 61496-1:2012 |
A.7 Muting A.7.1.2 There shall be at least two independent hard-wired muting signal sources to initiate the function. It shall not be possible to initiate muting when the OSSDs are already in the OFF-state. A.7.1.3 The mute function shall only be initiated by the correct sequence and/or timing of the mute signals. Should conflicting muting signals occur, the ESPE shall not allow a muted condition to occur. A.7.1.4 There shall be at least two independent hard-wired muting signal sources to stop the function. The muting function shall stop when the first of these muting signals changes state. The deactivation of the muting function shall not rely only on the clearance of the ESPE. A.7.1.5 The muting signals should be continuously present during muting. When the signals are not continuously present, an incorrect sequence and/or the expiration of a pre-set time limit shall cause either a lock-out condition or a restart interlock. A.7.4 Indication: A mute status signal or indicator shall be provided (in some applications, an indication signal of muting is necessary. |
IEC / TS 62046/Ed. 2:2008 |
5.5. General application requirements for muting |
ISO 13849-1:2015 |
5.2.2 Manual reset function |
ISO 12100:2010 |
6.2.11.4: Restart following power failure/spontaneous restart |
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Muting is the intended suppression of the safety function. In this FB, parallel muting with four muting sensors is specified.
This is required, e.g., when transporting the material into the danger zone without causing the machine to stop. Muting is triggered by muting sensors. The use of two or four muting sensors and correct integration into the production sequence must ensure that no persons enter the danger zone while the light curtain is muted. Muting sensors can be proximity switches, photoelectric barriers, limit switches, etc. which do not have to be fail-safe. Active muting mode must be indicated by indicator lights.
There are sequential and parallel muting procedures. In this FB, parallel muting with four muting sensors was used; an explanation is provided below. The FB can be used in both directions, forward and backward. The muting should be enabled with the MutingEnable signal by the process control to avoid manipulation.
The FB input parameters include the signals of the four muting sensors (MutingSwitch11 .. MutingSwitch22), the OSSD signal from the AOPD device (S_AOPD_In) as well as three parameterizable times (DiscTime11_12, DiscTime21_22 and MaxMutingTime).
The S_StartReset input shall only be activated if it is ensured that no hazardous situation can occur when the PES is started.
Name |
Data type |
Initial value |
Description, parameter values |
---|---|---|---|
VAR_INPUT |
|||
Activate |
BOOL |
FALSE |
|
S_AOPD_In |
BOOL |
FALSE |
Variable. OSSD signal from AOPD. FALSE: Protection field interrupted. TRUE: Protection field not interrupted. |
MutingSwitch11 |
BOOL |
FALSE |
Variable. Status of muting sensor 11. FALSE: Muting sensor 11 not actuated. TRUE: Workpiece actuates muting sensor 11. |
MutingSwitch12 |
BOOL |
FALSE |
Variable. Status of muting sensor 12. FALSE: Muting sensor 12 not actuated. TRUE: Workpiece actuates muting sensor 12. |
MutingSwitch21 |
BOOL |
FALSE |
Variable. Status of muting sensor 21. FALSE: Muting sensor 21 not actuated. TRUE: Workpiece actuates muting sensor 21. |
MutingSwitch22 |
BOOL |
FALSE |
Variable. Status of muting sensor 22. FALSE: Muting sensor 22 not actuated. TRUE: Workpiece actuates muting sensor 22. |
MutingEnable |
BOOL |
FALSE |
Variable or constant. Command by the control system that enables the start of the muting function when needed by the machine cycle. After the start of the muting function, this signal can be switched off. FALSE: Muting not enabled. TRUE: Start of muting function enabled. |
S_StartReset |
BOOL |
FALSE |
|
Reset |
BOOL |
FALSE |
|
DiscTime11_12 |
TIME |
T#0s |
Constant 0..4 s; Maximum discrepancy time for MutingSwitch11 and MutingSwitch12. |
DiscTime21_22 |
TIME |
T#0s |
Constant 0..4 s; Maximum discrepancy time for MutingSwitch21 and MutingSwitch22. |
MaxMutingTime |
TIME |
T#0s |
Constant 0..120 min (application area specific); Maximum time for complete muting sequence, timer started when first 2 muting sensors are actuated. |
VAR_OUTPUT |
|||
Ready |
BOOL |
FALSE |
|
S_AOPD_Out |
BOOL |
FALSE |
Safety related output, indicates status of the muted guard. FALSE: AOPD protection field interrupted and muting not active. TRUE: AOPD protection field not interrupted or muting active. |
S_MutingActive |
BOOL |
FALSE |
Indicates status of muting process. FALSE: Muting not active. TRUE: Muting active. |
SafetyDemand |
BOOL |
FALSE |
Optional. |
ResetRequest |
BOOL |
FALSE |
Optional. |
Error |
BOOL |
FALSE |
|
DiagCode |
WORD |
16#0000 |
Example for SF_MutingPar in forward direction with four sensors
1
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If the muting sensors MutingSwitch11 (MS_11) and MutingSwitch12 (MS_12) are activated by the product within the time DiscTime11_12, muting mode is activated (S_MutingActive = TRUE).
The MaxMutingTime starts with the first actuated muting sensor.
2
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Muting mode remains active as long as MutingSwitch11 (MS_11) and MutingSwitch12 (MS_12) are activated by the product. The product may pass through the light curtain without causing a machine stop.
3
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Before muting sensors MutingSwitch11 (MS_11) and MutingSwitch12 (MS_12) are disabled, muting sensors MutingSwitch21 (MS_21) and MutingSwitch22 (MS_22) must be activated. This ensures that muting mode remains active. The time discrepancy between switching of MutingSwitch21 and MutingSwitch22 is monitored by the time DiscTime21_22.
4
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Muting mode is terminated if either muting sensor MutingSwitch21 (MS_21) or MutingSwitch22 (MS_22) is disabled by the product. The maximum time for muting mode to be active is the MaxMutingTime.
Muting conditions
Forward direction
Muting condition 1 (to 8010) (MS_11 is the first entry switch actuated). Start timers MaxMutingTime and DiscTime11_12: MutingEnable AND (R_TRIG at MS_11 AND NOT MS_12 AND NOT MS_21 AND NOT MS_22)
Muting condition 1 (to 8310) (MS_12 is the first entry switch actuated). Start timers MaxMutingTime and DiscTime11_12: MutingEnable AND (NOT MS_11 AND R_TRIG at MS_12 AND NOT MS_21 AND NOT MS_22)
Muting condition 2 (from 8010) (MS_12 is the second entry switch actuated). Stop timer DiscTime11_12:
MutingEnable AND (MS_11 AND R_TRIG at MS_12 AND NOT MS_21 AND NOT MS_22)
Muting condition 2 (from 8310) (MS_11 is the second entry switch actuated). Stop timer DiscTime11_12:
MutingEnable AND (R_TRIG at MS_11 AND MS_12 AND NOT MS_21 AND NOT MS_22)
Muting condition 3 (both entry switches actuated in same cycle). Start timer MaxMutingTime:
MutingEnable AND (R_TRIG at MS_11 AND R_TRIG at MS_12 AND NOT MS_21 AND NOT MS_22)
Muting condition 4 (all switches actuated): MS_11 AND MS_12 AND MS_21 AND MS_22
Muting condition 24 (to 8030) (MS_21 is the first exit switch actuated). Start timer DiscTime21_22: MS_11 AND MS_12 AND R_TRIG at MS_21 AND NOT MS_22
Muting condition 24 (to 8330) (MS_22 is the first exit switch actuated). Start timer DiscTime21_22: MS_11 AND MS_12 AND NOT MS_21 AND R_TRIG at MS_22
Muting condition 25 (from 8030) (MS_22 is the second exit switch actuated). Stop timer DiscTime21_22: MS_11 AND MS_12 AND MS_21 AND R_TRIG at MS_22
Muting condition 25 (from 8330) (MS_21 is the second exit switch actuated). Stop timer DiscTime21_22: MS_11 AND MS_12 AND R_TRIG at MS_21 AND MS_22
Muting condition 5 (one of the exit switches released). Stop timer MaxMutingTime: NOT MS_11 AND NOT MS_12 AND (F_TRIG at MS_21 OR F_TRIG at MS_22)
Backward direction
Muting condition 11 (to 8110) (MS_21 is the first entry switch actuated). Start timers MaxMutingTime and DiscTime21_22: MutingEnable AND (NOT MS_22 AND R_TRIG at MS_21 AND NOT MS_11 AND NOT MS_12)
Muting condition 11 (to 8410) (MS_22 is the first entry switch actuated). Start timers MaxMutingTime and DiscTime21_22: MutingEnable AND (R_TRIG at MS_22 AND NOT MS_21 AND NOT MS_11 AND NOT MS_12)
Muting condition 12 (from 8110) (MS_22 is the second entry switch actuated). Stop timer DiscTime21_22:
MutingEnable AND (MS_21 AND R_TRIG at MS_22 AND NOT MS_11 AND NOT MS_12)
Muting condition 12 (from 8410) (MS_21 is the second entry switch actuated) . Stop timer DiscTime21_22:
MutingEnable AND (R_TRIG at MS_21 AND MS_22 AND NOT MS_11 AND NOT MS_12)
Muting condition 13 (both entry switches actuated in same cycle). Start timer MaxMutingTime:
MutingEnable AND (R_TRIG at MS_21 AND R_TRIG at MS_22 AND NOT MS_11 AND NOT MS_12)
Muting condition 14 (all switches actuated): MS_11 AND MS_12 AND MS_21 AND MS_22
Muting condition 44 (to 8130) (MS_11 is the first exit switch actuated). Start timer DiscTime11_12: MS_21 AND MS_22 AND R_TRIG at MS_11 AND NOT MS_12
Muting condition 44 (to 8430) (MS_12 is the first exit switch actuated). Start timer DiscTime11_12: MS_21 AND MS_22 AND NOT MS_11 AND R_TRIG at MS_12
Muting condition 45 (from 8130) (MS_12 is the second exit switch actuated). Stop timer DiscTime11_12: MS_21 AND MS_22 AND MS_11 AND R_TRIG at MS_12
Muting condition 45 (from 8430) (MS_11 is the second exit switch actuated). Stop timer DiscTime11_12: MS_21 AND MS_22 AND R_TRIG at MS_11 AND MS_12
Muting condition 15 (one of the exit switches released). Stop timer MaxMutingTime: NOT MS_21 AND NOT MS_22 AND (F_TRIG at MS_11 OR F_TRIG at MS_12)
Wrong muting sequences:
- State 8000
-
(MutingEnable = FALSE when muting sequence starts) OR
((MS_11 OR MS_12) AND (MS_21 OR MS_22)) OR
(R_TRIG at MS_11 AND MS_12 AND NOT R_TRIG at MS_12) OR
(R_TRIG at MS_12 AND MS_11 AND NOT R_TRIG at MS_11) OR
(R_TRIG at MS_21 AND MS_22 AND NOT R_TRIG at MS_22) OR
(R_TRIG at MS_22 AND MS_21 AND NOT R_TRIG at MS_21) OR
((MS_11 AND NOT R_TRIG at MS_11) AND (MS_12 AND NOT R_TRIG at MS_12)) OR
((MS_21 AND NOT R_TRIG at MS_21) AND (MS_22 AND NOT R_TRIG at MS_22))
- State 8010
-
NOT MutingEnable OR NOT MS_11 OR MS_21 OR MS_22
- State 8310
-
NOT MutingEnable OR NOT MS_12 OR MS_21 OR MS_22
- State 8020
-
NOT MS_11 OR NOT MS_12
- State 8040
-
R_TRIG at MS_11 OR R_TRIG at MS_12 OR R_TRIG at MS_21 OR R_TRIG at MS_22
OR ((MS_11 OR MS_12) AND (F_TRIG at MS_21 OR F_TRIG at MS_22)) OR ((F_TRIG at MS_11 OR F_TRIG at MS_12) AND (F_TRIG at MS_21 OR F_TRIG at MS_22))
- State 8030
-
NOT MS_11 OR NOT MS_12 OR NOT MS_21
- State 8330
-
NOT MS_11 OR NOT MS_12 OR NOT MS_22
- State 8110
-
NOT MutingEnable OR MS_11 OR MS_12 OR NOT MS_21
- State 8410
-
NOT MutingEnable OR MS_11 OR MS_12 OR NOT MS_22
- State 8120
-
NOT MS_21 OR NOT MS_22
- State 8140
-
R_TRIG at MS_11 OR R_TRIG at MS_12 OR R_TRIG at MS_21 OR R_TRIG at MS_22
OR ((MS_21 OR MS_22) AND (F_TRIG at MS_11 OR F_TRIG at MS_12)) OR ((F_TRIG at MS_11 OR F_TRIG at MS_12) AND (F_TRIG at MS_21 OR F_TRIG at MS_22))
- State 8130
-
NOT MS_21 OR NOT MS_22 OR NOT MS_11
- State 8430
-
NOT MS_21 OR NOT MS_22 OR NOT MS_12
Typical timing diagram
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Error detection
The FB detects the following error conditions:
-
DiscTime11_12 and DiscTime21_22 have been set to values less than T#0s or greater than T#4s.
-
MaxMutingTime has been set to a value less than T#0s or greater than T#120min.
-
The discrepancy time for the MutingSwitch11/MutingSwitch12 or MutingSwitch21/MutingSwitch22 sensor pairs has been exceeded.
-
The muting function (S_MutingActive = TRUE) exceeds the maximum muting time MaxMutingTime.
-
Muting sensors MutingSwitch11, MutingSwitch12, MutingSwitch21, and MutingSwitch22 are activated in the wrong order.
-
Muting sequence starts without being enabled by MutingEnable.
-
A static Reset condition is detected in states 8401 and 8402.
Error behavior
In the event of an error, the S_AOPD_Out and S_MutingActive outputs are set to FALSE. The DiagCode output indicates the relevant error code and the Error output is set to TRUE.
A restart is inhibited until the error conditions are cleared and the safe state is acknowledged with Reset by the operator.
Function block-specific error and status codes
DiagCode |
State name |
State description and output setting |
---|---|---|
C001 |
Reset Error 1 |
Static Reset condition detected after FB activation in state 8401. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = TRUE |
C011 |
Reset Error 2 |
Static Reset condition detected in state 8402. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = TRUE |
CYx4 |
Error Muting sequence |
Error detected in muting sequence state 8000, 8010, 8310, 8020, 8040, 8030, 8330, 8110, 8410, 8120, 8140, 8130 or 8430. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = TRUE Y = Status in the sequence (6 states for forward and 6 states for backward direction). C0x4 = Error occurred in state 8000 C1x4 = Error occurred in state Forward 8010 C2x4 = Error occurred in state Forward 8310 C3x4 = Error occurred in state Forward 8020 C4x4 = Error occurred in state Forward 8030 C5x4 = Error occurred in state Forward 8330 C6x4 = Error occurred in state Forward 8040 C7x4 = Error occurred in state Backward 8110 C8x4 = Error occurred in state Backward 8410 C9x4 = Error occurred in state Backward 8120 CAx4 = Error occurred in state Backward 8130 CBx4 = Error occurred in state Backward 8430 CCx4 = Error occurred in state Backward 8140 ... CFx4 = Muting enable missing x = Status of the sensors when error occurred (4 bits: LSB = MS_11; MS_12; MS_21; MSB = MS_22). |
C010 |
Parameter Error |
DiscTime11_12, DiscTime21_22 or MaxMutingTime value out of range. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = TRUE |
C020 |
Error Timer MaxMuting |
Timing error: Active muting time (when S_MutingActive = TRUE) exceeds MaxMutingTime. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = TRUE |
C030 |
Error Timer MS11_12 |
Timing error: Discrepancy time for switching MutingSwitch11 and MutingSwitch12 > DiscTime11_12. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = TRUE |
C040 |
Error Timer MS21_22 |
Timing error: Discrepancy time for switching MutingSwitch21 and MutingSwitch22 > DiscTime21_22. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = TRUE |
DiagCode |
State name |
State description and output setting |
---|---|---|
0000 |
Idle |
The function block is not active (initial state). Ready = FALSE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8000 |
AOPD Free |
Muting not active and no safety demand from AOPD. If timers from subsequent muting are still running, they are stopped. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8401 |
Init |
Function block has been activated. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = TRUE Error = FALSE |
8802 |
Safety Demand AOPD |
Safety demand detected by AOPD, muting not active. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = TRUE ResetRequest = FALSE Error = FALSE |
8402 |
Wait for Reset |
Safety demand or errors have been detected and are now cleared. Operator acknowledgment by Reset required. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = TRUE Error = FALSE |
8002 |
Safe |
Safety function activated. Ready = TRUE S_AOPD_Out = FALSE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8010 |
Muting Forward Start 1 |
Muting forward sequence is in starting phase after rising trigger of MutingSwitch 11. Monitoring of DiscTime11_12 is activated. Monitoring of MaxMutingTime is activated. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8310 |
Muting Forward Start 2 |
Muting forward sequence is in starting phase after rising trigger of MutingSwitch 12. Monitoring of DiscTime11_12 is activated. Monitoring of MaxMutingTime is activated. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8020 |
Muting Forward Active 1 |
Muting forward sequence is active either:
Monitoring of DiscTime11_12 is stopped. Monitoring of MaxMutingTime is activated, when transition came directly from state 8000. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = TRUE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8030 |
Muting Forward Step 1 |
Muting forward sequence is active. MutingSwitch21 is the first exit switch actuated. Monitoring of DiscTime21_22 is started. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = TRUE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8330 |
Muting Forward Step 2 |
Muting forward sequence is active. MutingSwitch22 is the first exit switch actuated. Monitoring of DiscTime21_22 is started. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = TRUE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8040 |
Muting Forward Active 2 |
Muting forward sequence is still active. Both MutingSwitch21 and 22 are actuated, the monitoring of DiscTime21_22 is stopped. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = TRUE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8110 |
Muting Backward Start 1 |
Muting backward sequence is in starting phase after rising trigger of MutingSwitch21. Monitoring of DiscTime21_22 is activated. Monitoring of MaxMutingTime is activated. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8410 |
Muting Backward Start 2 |
Muting backward sequence is in starting phase after rising trigger of MutingSwitch22. Monitoring of DiscTime21_22 is activated. Monitoring of MaxMutingTime is activated. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = FALSE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8120 |
Muting Backward Active 1 |
Muting backward sequence is active either:
Monitoring of DiscTime21_22 is stopped. Monitoring of MaxMutingTime is activated, when transition came directly from state 8000. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = TRUE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8130 |
Muting Backward Step 1 |
Muting backward sequence is active. MutingSwitch11 is the first exit switch actuated. Monitoring of DiscTime11_12 is started. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = TRUE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8430 |
Muting Backward Step 2 |
Muting backward sequence is active. MutingSwitch12 is the first exit switch actuated. Monitoring of DiscTime11_12 is started. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = TRUE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |
8140 |
Muting Backward Active 2 |
Muting backward sequence is still active. Both exit switches MutingSwitch11 and 12 are actuated, the monitoring of DiscTime11_12 is stopped. Ready = TRUE S_AOPD_Out = TRUE S_MutingActive = TRUE SafetyDemand = FALSE ResetRequest = FALSE Error = FALSE |