4 Safety Function Blocks
4 - 72
NX-series Safety Control Unit Instructions Reference Manual (Z931)
• Muting is used to intentionally disable a safety function. Muting is used, for example, to pass a work-
piece through a hazardous area without stopping the machine. Muting is activated by muting sen-
sors. Four muting sensors are used. To correctly incorporate the safety function into a manufacturing
process, you must ensure that people will not enter the hazardous area while the light curtain is being
muted. Proximity sensors, photoelectric barriers, limit switches, and other devices that do not have
failsafe mechanisms are used for muting sensors. Muting operation must be indicated by indicator
lights.
• There are two types of muting: parallel and sequential. This FB performs parallel muting with four
muting sensors. Passing into a hazardous area in the forward direction is described below. (Refer to
SF_MutingPar Instruction Application Example for Forward Entry with Four Sensors
The FB can be used for either forward or backward passage. To prevent manual operation, muting
must also be enabled by process control with the
MutingEnable
signal to perform muting.
• The input parameters to the FB include four muting sensor signals (
MutingSwitch11
to
MutingSwitch22
), an OSSD signal from a photoelectric protection device (
S_AOPD_In
), and three
time parameters (
DiscTime11_12
,
DiscTime21_22
, and
MaxMutingTime
).
• Activate the
S_StartReset
input only when you can ensure that no hazardous state will occur as the
result of starting the Safety CPU Unit.
• A FB error will occur if the same variable is assigned to the input and the discrepancy time is set to 0.
SF_MutingPar Instruction Application Example for Forward Entry with Four
Sensors
Function
Order
Diagram
Description
1
Muting mode is enabled
(
S_MutingActive
= TRUE) when the pas-
sage of a workpiece turns ON
MutingSwitch11
(MS_11) and
MutingSwitch12
(MS_12) within the time
set by
DiscTime11_12
.
2
Muting mode is enabled as long as
MutingSwitch11
(MS_11) and
MutingSwitch12
(MS_12) remain ON
due to the workpiece. This allows the
workpiece to pass through the light cur-
tain without stopping the machine.
3
MutingSwitch21
(MS_21) and
MutingSwitch22
(MS_22) must turn ON
before
MutingSwitch11
(MS_11) and
MutingSwitch12
(MS_12) turn OFF. This
ensures that muting mode remains ON.
The discrepancy time between
MutingSwitch21
and
MutingSwitch22
is
monitored for the time that is set in
DiscTime21_22
.
4
Muting mode is ended if only
MutingSwitch22
(MS_22) is ON. Muting
mode is ended if
MutingSwitch21
(MS_21) or
MutingSwitch22
(MS_22)
turns OFF due to the workpiece. The
maximum time that the muting mode is
enabled is set by
MaxMutingTime
.
MS_11
MS_21
MS_22
MS_12 Receiver
Transmitter
Danger
zone
MS_11
MS_21
MS_22
MS_12 Receiver
Transmitter
Danger
zone
Danger
zone
MS_11
MS_21
MS_22
MS_12 Receiver
Transmitter
MS_11
MS_21
MS_22
MS_12 Receiver
Transmitter
Danger
zone
Содержание NX-SL series
Страница 8: ...CONTENTS 6 NX series Safety Control Unit Instructions Reference Manual Z931 ...
Страница 14: ...Terms and Conditions Agreement 12 NX series Safety Control Unit Instructions Reference Manual Z931 ...
Страница 28: ...Sections in this Manual 26 NX series Safety Control Unit Instructions Reference Manual Z931 ...
Страница 98: ...2 Standard Functions 2 64 NX series Safety Control Unit Instructions Reference Manual Z931 ...
Страница 104: ...2 Standard Functions 2 70 NX series Safety Control Unit Instructions Reference Manual Z931 ...
Страница 110: ...2 Standard Functions 2 76 NX series Safety Control Unit Instructions Reference Manual Z931 ...
Страница 130: ...3 Safety Standard Function Blocks 3 20 NX series Safety Control Unit Instructions Reference Manual Z931 ...
Страница 265: ...I 1 I NX series Safety Control Unit Instructions Reference Manual Z931 Index ...
Страница 268: ...I 4 NX series Safety Control Unit Instructions Reference Manual Z931 Index ...
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