IDEC DS2_Series - Manual (Page 11)

DS2 series Instruction manual
10
5. FUNCTIONING MODES
The DS2 light grids detect and measure objects placed inside the detection area. Hence, beam
interruptions can cause output switching, analogue output signal variation and serial output updating.
Small objects (up to 12 mm) detection and geometrical measurements determined with approximately 6
mm resolution can be obtained by setting the device according to the different functioning modes.
Beam scanning is sequential and the update of all the outputs is made at each scanning, within a period
equal to the device response time.
5.1. Detection mode
The detection mode is activated whenever at least one beam is interrupted inside the detection area.
The activation causes the digital output switching (signalled by the powering of the yellow LED). The
DS2 presents many different functions, listed below, that condition the switching output:
• Switching Output Mode: indicates if electrical current passes through switching output; the output
can be normally closed (N.C.) or normally open (N.O.).
• Switching Output Delay: delays the re-setting of the switching output after detection. The delay
time can be selected.
• Acquisition and detection (Teach-in): allows a conditioned detection of the object inside the
detection area: if the object corresponds (without resolution) to the object detected during the Teach-
in phase, the output switches. On the contrary nothing happens. The following modes can be set:
- absolute Teach-in detection: the output switches only if the previously set object is re-detected
in the same position.
- relative Teach-in detection: the output switches only if the previously set object (without
resolution) is re-detected, independently from the position in the sensing area.
5.2. Measurement mode
The measurement mode depends on the number of interrupted beams and causes the switching of
the analogue output and of the serial output (and also of the digital output).
The DS2 presents many different measurement functions, listed here below:
• Absolute measurements: measurement is obtained considering the first photoelement (1) as the
reference beam beginning from the connector side. The DS2 light grid has in particular the following
functions:
1. top beam: provides the measurement between the reference beam and the obscured beam
furthest away from the reference
2. bottom beam: provides the measurement from the reference beam and the obscured beam
closest to the reference
3. middle beam: provides the measurement of the beam corresponding to the medium point
between the obscured beam furthest away from the reference and the obscured beam closest to
the reference
• Relative measurements: measurement is obtained not considering absolute references. The
measurement depends on the number of obscured beams. The DS2 light grid has in particular the
following functions:
4. total beams: supplies the measurement corresponding to the total number of obscured beams
5. total contiguous beams: supplies the measurement corresponding to the maximum number of
contiguous beams obscured