CET s.r.l. Parallel Message Display
page 14
3.
TECHNICAL DESCRIPTION
3.1. INPUTS
The device terminal board is provided with 14 signal inputs, which can be used with either POSITIVE LOGIC by
programming the PRI input to EARTH or NEGATIVE LOGIC with PRI at +24Vdc.
The inputs must be connected as shown in the figure according to the type of logic used (POSITIVE or
NEGATIVE).
3.1.1. Using inputs in POSITIVE logic
PRI +24 GND
PRI +24 GND
9
A
B
D0
Dn
C PNP E
GND-EARTH
EXTERNAL
POWER UNIT
GND +24Vdc
C = Collector
E = Emitter
DISPLAY UNIT
C PNP E
C PNP E
C PNP E