
6. CONNECTION OF I/O UNITS TO
MACHINE INTERFACE
B–63783EN/01
216
The input signal to the source output operator’s panel connection unit is
input over a non–insulated interface, and is called “DC input signal A.”
(1) DC input signal A
DC input signal A is sent to the NC from the machine tool by
pushbuttons, limit switches, relay contacts and proximity switches.
Most receivers are sink types. However, some inputs can be switched
to source type. (Use of sink–type receivers is required in safety
standards.)
(a) Satisfy the machine–side contact conditions:
Contact capacitance: 30 VDC, 16 mA min.
Leak current between contacts in open circuit:
1 mA min. (voltage 26.4 V)
Voltage drop between contacts in closed circuit:
2 V max. (including cable voltage drop)
(b)Input receiver circuit
Sink–type connection:
safety standard compliant
(24 V common)
Filter and level
conversion circuit
Receiver
output
signal
R
+24 V
+24 V
Input signal
Source output operator’s panel connection unit
Fig. 6.10.1 (a) Sink–type receiver circuit
6.10.1
Source Output
Operator’s Panel
Connection Unit Input
Signal Standard