SG4E Full Rev01.pdf - Datasensor

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SG4-E INSTRUCTION MANUAL
7.10 CASCADE
A dedicated Bus provides the connection between master and slave units. The same bus is
used to connect SG-Dongle which links the light curtain to Ethernet.
A proprietary transmission protocol for bus is used to communicate to slaves safety related
informations and status.
OSSDs are physically connected to master unit only; only the master unit can control their
status.
If transmission fails, due to a stuck-at fault or a signal degradation, master and slave units go
in failure lock-out condition.
A maximum of three units (master and two slaves) can be connected in a cascade
configuration (a maximum of 160 beams for 30mm resolution models and a maximum of 320
beams for 14mm resolution models). The maximum length of the master unit is 1800mm and
the maximum length of each slave is 1200mm. For the correct connection of the units in a
cascade configuration, the right cables have to be used (CVL-5193, CVL-5194, CVL-5195 on
chapter 15).
A safe auto-recognition procedure at startup is implemented; it automatically detects cascade
topology and correctly address units.
In order to allow auto-recognition it’s mandatory to connect the termination cap (supplied on
kit) on the tail connector of last cascade unit, in both transmitter and receiver unit.
If this connection misses, Master and Slave units go in critical Communication failure.
7.11 PNP/NPN
The PNP/NPN function allows the user to inform the light curtain on how the OSSDs are
connected.
PNP CONFIGURATION
In this configuration the load is connected between
OSSD output and GND.
In normal operation OSSDs output voltage is 24VDC.
When an opaque object intercepts the beams the status
of OSSDs changes from high to low.
Fig. 55 – PNP connection
Fig. 56 – PNP timings
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