. . . . .
OMRON SCIENTIFIC TECHNOLOGIES INC.
Fremont CA USA
Tel: 1/888/510-4357 in USA and Canada
© OSTI 1209 PN99584-0050 Rev. E
Original Instructions
21
5.3 F
LOATING
B
LANKING
Up to two channels can be disabled at any location in the detection zone without the 4700 system going
to the machine stop state. The disabled channels are not fixed at a single location but “float” through
the detection zone.
See
for a diagram of 4700 system response during operation with Floating Blanking active.
Table 5-3
Floating
Blanking
Inactive
1
Channel
Floating
Blanking
Active
1
Channel
Floating
Blanking
Active
1
Channel
Floating
Blanking
Active
1
Channel
Floating
Blanking
Active
2
Channel
Floating
Blanking
Active
2
Channel
Floating
Blanking
Active
2
Channel
Floating
Blanking
Active
2
Channel
Floating
Blanking
Active
2
Channel
Floating
Blanking
Active
2
Channel
Floating
Blanking
Active
2
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
0
Exceptions
machine
run
1
Exception
machine
run
2
Exceptions
machine
run
2
Exceptions
machine
run
3
Exceptions
machine
stop
3
Exceptions
machine
stop
3
Exceptions
machine
stop
System Response to Floating Blanking
Table 5-4
Symbol
Description
Optical channel is not blocked.
Optical channel is blocked.
Optical channel is selected by Exact Channel Select.
Optical channel is selected by Exact Channel Select and is blocked.
Icon Key for Tables 5-1 and 5-2
5.4 U
SING
E
XACT
C
HANNEL
S
ELECT
WITH
F
LOATING
B
LANKING
▲
!
Warning!
Using Exact Channel Select with Floating Blanking is an advanced feature. All situations which
may occur to the 4700 system detection zone must be carefully considered. The 4700 system is less sensitive to
objects in the detection zone. The safety distance must be increased. Failure to do so may cause serious injury.
When both Exact Channel Select and Floating Blanking are selected, the floating channels are allowed
to occur anywhere within the detection zone, even within the area selected by Exact Channel Select. In
these areas, a channel that should normally be blocked is allowed to be clear.
5.4.1
T
HE
E
FFECT
OF
E
XACT
C
HANNEL
S
ELECT
AND
F
LOATING
B
LANKING
ON
M
INIMUM
O
BJECT
R
ESOLUTION
When Exact Channel Select and/or Floating Blanking is active, the safety distance is affected. Exact
Channel Select and Floating Blanking desensitize the light curtain and increase the size of the
minimum object detected. The increase is equal to the channel spacing distance for each channel that is
disabled.
• A 4700 system with 12 mm minimum object resolution and one channel disabled has a minimum object
sensitivity of:
12 mm + 6.25 mm = 18.25 mm (0.72 inches).