
B–63833EN/03
8. CONNECTING MACHINE INTERFACE I/O
124
NOTE
Output signal driver
Each of the output signal driver devices used on this I/O
board outputs eight signals.
A driver device monitors the current of each output signal.
If it detects an overcurrent on an output, it turns off the
output. Once an overcurrent causes an output to turn off,
the overcurrent is no longer present. Then, the output is
turned on again. In ground–fault or overload conditions,
outputs may turn on and off alternately. This phenomenon
also occurs when a load with a high surge current is
connected.
Each driver device contains an overheat detector circuit. If
an overcurrent is observed on an output continuously
because of a ground–fault or similar reason and the
temperature in the device rises, the overheat detector circuit
turns off all eight outputs. The output–off state is
maintained. This state can be released by logically turning
off then on again the outputs after the internal temperature
of the device drops to a specified level. This state can also
be released by turning off the system power supply.
The output signals of the driver devices are assigned the
following addresses:
Device #0: Y1000.0 to Y1000.7
Device #1: Y1001.0 to Y1001.7
Device #2: Y1002.0 to Y1002.7
Device #3: Y1003.0 to Y1003.7
Device #4: Y1004.0 to Y1004.7
Device #5: Y1005.0 to Y1005.7
Device #6: Y1006.0 to Y1006.7
Device #7: Y1007.0 to Y1007.7
If NC diagnosis shows that an output is on but the output is
actually not turned on, an overload on that output or another
output in the same device may have turned off the eight
outputs of that device. In such a case, turn off the system
power supply and remove the cause of the overload.