KEYENCE BL-600 Series - Manual (Page 97)

87
Chapter 6 Functions for Reading Operation
6
Note: 5 seconds after the power switch turns on or an UNLOCK command ( ➮ See
page 116.) is sent, the unit will not start reading a bar code by turning on the trigger
input.
One-shot signal trigger
The BL-600 Series detects when the trigger input turns on and starts reading bar
codes for the preset “One shot input time”.
➮ See page 44. The laser turns off after the
number of the bar code reading reaches the specified decoding match count.
➮ See page 43. The BL-600 Series then sends the read data.
The rest of the operation is the same as that for the “Level signal” method.
Use the one-shot signal trigger when the one shot input time is extremely short or
to fix the scanning time.
Reference 1: The BL-600 can read up to 4 types of bar codes without changing
the bar code type setting.
➮ See page 49.
Reference 2: Pressing the TEST switch lightly (for less than 2 seconds) serves as
a trigger input (The laser turns on once.).
➮ See page 8.
■ Timing diagram
*1 After the trigger input exceeds the preset input times, the laser begins to emit.
Trigger input minimum ON time:
5 ms (when the trigger input value is 2 ms)
15 ms (when the trigger input value is 10 ms)
Note: The BL-600 has a built-in AGC (auto gain control) circuit. It requires a
maximum of 3 scans (6 ms) to adjust gain. The BL-600 generates a maximum of 6
ms delay until starting to read the data after the laser beam turns ON.
OK/NG NG
<Succeed to read> <Fail to read>
Trigger input
Bar code
*1
Preset input time Preset input time
Laser beams
Communication time
OK/NG output