NAiS FP Series, Hardware Manual

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FP0 Hardware Wiring
9-2 Matsushita Electric Works (Europe) AG
9.1 Safety Instructions
In certain applications, malfunction may occur for the following reasons:
Power ON timing differences between the FP0 control unit and I/O
or motorized devices
An operation time lag when a momentary power drop occurs
Abnormality in the FP0 unit, power supply circuit, or other devices
In order to prevent a malfunction resulting in system shutdown choose the adequate
safety circuits or other safety measures listed in the following:
9.1.1 Interlock Circuit
When a motor clockwise/counter-clockwise operation is controlled, provide an interlock
circuit that prevents clockwise and counter-clockwise signals from being input into the
motor at the same time.
9.1.2 Emergency Stop Circuit
Add an emergency stop circuit to controlled devices in order to prevent a system
shutdown or an irreparable accident when malfunction occurs.
9.1.3 Start Up Sequence
The FP0 should be operated after all of the outside devices are energized. To keep this
sequence, the following measures are recommended:
D
Set the mode switch from PROG. mode to RUN mode after power is
supplied to all of the outside devices
D
Program the FP0 so as to disregard the inputs and outputs until the
outside devices are energized
Note
When stopping the operation of FP0, also have the I/O devices
turned OFF after the FP0 has stopped operating.
9.1.4 Momentary Power Failures
If the duration of the power failure is less than 5ms, the FP0 continues to operate. If the
power is OFF for 5ms or longer, operation changes depending on the combination of
units, the power supply voltage, and other factors. (In some cases, operation may be
the same as that for a power supply reset.)
If operation is to be continued following recovery from the momentary power failure, use
an automatic retaining sequence program that uses a hold type internal relay.