Omron MS4800E, Operation Manual

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13
Floating Blanking
Section 5-2
5-2 Floating Blanking
!WARNING
Use of Fixed Blanking and Floating Blanking will make the MS4800 system
less sensitive to objects in the detection zone. Improper use of these features
can result in severe injury to personnel. Fixed Blanking may require a hard
barrier. Fixed Blanking and Floating Blanking may require an increase in the
safety distance. Read the following section carefully.
One channel can be obstructed at any location in the detection zone as long
as the optical synchronization is maintained. Please refer to chapter
5-4 Opti-
cal Synchronization for further details.
This means that an object can freely float from one end of the protective field
to the other without the MS4800 system entering the MACHINE STOP state.
The obstructed channels are not fixed at a single location but "float" through
the detection zone.
Note Please refer for further information to the FAQ to section 17-6.
5-2-1 Selecting Floating Blanking with selector switches
Using the selector switches an authorized user can activate the Floating
Blanking function. This allows the system to operate with one obstructed opti-
cal beam anywhere within the protected zone. This obstruction is permitted
anywhere within the protected zone and is permitted to move over time. After
setting the appropriate selector switches, the receiver enters the Power-On
Self Test state and if no faults are detected the receiver shall enter the INTER-
LOCK or MACHINE RUN condition depending upon the selected operating
mode.
!WARNING
Two-Beam Floating Blanking is not available on the MS4800 system.
Floating
Blanking
Inactive
1
Channel
Floating
Blanking Active
1
Channel
Floating
Blanking Active
1
Channel
Floating
Blanking Active
1
Channel
Floating
Blanking Active
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
System
Response
1
Exception
MACHINE STOP
0
Exceptions
Machine
Run
1
Exception
Machine
Run
2
Exceptions
MACHINE STOP
2
Exceptions
MACHINE STOP
Clear Optical Channel
Optical Channel is obstructed
Floating Blanking Effects on Minimum Object Resolution
Standard Minimum Object Resolution
(No Floating Blanking) Minimum Object Resolution with
1 Beam Blanking
14 mm 24 mm
30 mm 50 mm