KEYENCE BL-180 - Manual (Page 20)

2.2 Read modes
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2.2 Read modes
The BL-180 provides 4 types of read modes.
2.2.1 Single label read mode
This mode allows the unit to read one bar code during one trigger input signal.
The operation and timing chart are described on page 10.
2.2.2 Multi-label read mode 1 (Multi 1)
This mode allows the unit to read several bar codes printed on one label as shown
below during one trigger input signal. The unit outputs the readout data sequen-
tially.
Multi-label read mode 1 operation
In the multi-label read mode 1, the unit reads several bar codes continuously, and
outputs them sequentially as it reads while LED beam remains on and trigger in-
put turns on after bar codes have been read (or during the preset input time if one-
shot signal trigger is selected).
To prevent the unit from reading the same bar code twice, the time for one bar
code to pass across the LED beam’s field and read, plus the repeat reading time
must be set (100 ms to 25.5 s). During the repeat reading time, the unit cannot
read the same bar code repeatedly, but can read different bar codes.
A reading error is issued only when the unit cannot read any bar code while the
trigger input is on.
For OK/NG output, “OK” turns on every time the unit reads a bar code and “NG”
turns on if the unit fails to read a bar code. (Comparison to the preset data is not
performed.)
Repeat reading time
OK NG
Trigger input
Bar code
LED beams
Communication time
OK/NG output
OK OK OK