Description ODSL 30
Leuze electronic
ODSL 30
27
TNT
35/7-2
4
V
Behaviour of the switching outputs of the ODSL 30/D…
In addition, the ODSL 30/D… with serial output also has two switching outputs. The position
within the measuring range at which the switching outputs become active can be set arbi-
trarily via a teach line or via configuration. In addition to the switching points, it is also
possible to configure the switching hysteresis, the switching behaviour (light/dark switching),
and the type of switching output (PNP high active or NPN low active or PNP/NPN push-pull).
Teaching always takes place towards the upper switching point (see figure 3.7 on page 20).
The lower switching point is set to the value '199' by default and can be adjusted via the
operating menu. The following table applies for a lower switching point of 199mm.
Notes regarding the termination of the data lines of the ODSL 30/D 485…
The ODSL 30/D 485… features a combined transmitter and receiver component that can
transmit serial data according to the RS 485 and RS 422 standard (see TIA/EIA-485-A or
DIN66259, Part 3).
These standards define some basic rules that should be followed in order to achieve the
most reliable data transmission:
• The data lines A and B (which correspond to the ODSL 30 pins Tx+ and Tx-) are con-
nected to an intrinsic impedance of Z
0
120
via a 2-wire twisted pair cable.
• The end of the data line (and the beginning in case of RS 485) is terminated using a
120
resistor. The ODSL 30/D 485… does not have an internal bus termination.
• The RS 485 bus participants are wired in an in-line bus topology, i.e., the data line is
fed from one bus participant to the next. Cable stubs are to be avoided or to be kept
as short as possible.
• The RS 485 specification assumes an inactive potential difference of U
AB
200mV
between the data lines. A bus termination in the form of a voltage divider should be
implemented in order to maintain this level. Usually, it is connected to the RS 485
coupling module of the PLC.
The RS 485 specification permits transmission rates in the megabit range for up to
32 participants. The ODSL 30/D 485… is designed for a data transmission rate of typically
9600 Baud (600 … 115200 Baud may be configured). In practice, this means that the strict
requirements regarding the bus termination and the cabling are "softened" for a few bus
participants.
Object distance
Light switching
Dark switching
output Q1
output Q2
output Q1
output Q2
No object (no signal)
off
off
on
on
< 200mm
1)
1)
Only if a received signal is available that can still be evaluated, otherwise same as "no
object"
on
on
off
off
< teach value
on
on
off
off
> teach value
off
off
on
on