5-20
5.8 Safety Measures
5.8.1 Safety Measures
Precautions regarding system design
On the system using PLC, malfunction may occur for the following reasons:
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Power on timing differences between the PLC and input/output or mechanical power apparatus.
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Response time lag when a momentary power drop occurs.
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Abnormality in the PLC unit, external power supply, or other devices.
In order to prevent a malfunction resulting in system shutdown, choose the adequate safety measures
listed in the following:
Interlock circuit
When a motor clockwise/counter-clockwise operation is controlled, provide an interlock circuit externally.
Emergency stop circuit
Provide an emergency stop circuit to the PLC externally to turn off the power supply of the output device.
Start up sequence
The PLC should be started after booting the I/O device and mechanical power apparatus. To keep this
sequence, the following measures are recommended.
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Turn on the PLC with the mode selector set to the PROG. mode, and then switch to the RUN mode.
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Program the PLC so as to disregard the inputs and outputs until the outside devices are energized.
Note) In case of stopping the operation of the PLC also, have the input/output devices turned off after the
PLC has stopped operating.
Grounding
When installing the controller next to devices that generate high voltages from switching, such as
inverters, do not ground them together. Use an exclusive ground for each device.
5.8.2 Momentary Power Failures
Operation of momentary power failures
If the duration of the power failure is less than 5 ms, the FP0R continues to operate. If the power is off for
5 ms 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.)
5.8.3 Protection of Power Supply and Output Sections
Power supply
An insulated power supply with an internal protective circuit should be used. The power supply for the
control unit operation is a non-insulated circuit, so if an incorrect voltage is directly applied, the internal
circuit may be damaged or destroyed.
If using a power supply without a protective circuit, power should be supplied through a protective
element such as fuse.
Protection of output
If current exceeding the rated control capacity is being supplied in the form of a motor lock current or a
coil shorting in an electromagnetic device, a protective element such as a fuse should be attached
externally.
Summary of Contents for FP0R Series
Page 1: ......
Page 6: ...iv ...
Page 14: ...xii ...
Page 15: ...Chapter 1 Functions and Restrictions of the Unit ...
Page 24: ...1 10 ...
Page 25: ...Chapter 2 Specifications and Functions of Control Unit ...
Page 38: ...2 14 ...
Page 39: ...Chapter 3 Expansion ...
Page 45: ...3 7 3 4 Terminal layout diagram Model No Terminal layout diagrams E8RS E8RM E16RS E16RM E8YRS ...
Page 48: ...3 10 ...
Page 49: ...Chapter 4 I O Allocation ...
Page 53: ...Chapter 5 Installation and Wiring ...
Page 73: ...Chapter 6 Preparation of USB Port ...
Page 77: ...6 5 5 Click Finish on the following screen to be displayed ...
Page 79: ...6 7 4 Double click on FP0R 5 Click Update Driver ...
Page 84: ...6 12 ...
Page 85: ...Chapter 7 Communication ...
Page 139: ...7 55 Sample program For Type II Use a program as below to directly specify a MODBUS address ...
Page 141: ...Chapter 8 High speed Counter Pulse Output and PWM Output Functions ...
Page 142: ...8 2 ...
Page 199: ...Chapter 9 Security Functions ...
Page 211: ...Chapter 10 Other Functions ...
Page 217: ...Chapter 11 Self Diagnostic and Troubleshooting ...
Page 227: ...Chapter 12 Precautions During Programming ...
Page 242: ...12 16 ...
Page 243: ...Chapter 13 Specifications ...
Page 254: ...13 12 ...
Page 255: ...Chapter 14 Dimensions and Others ...
Page 262: ...14 8 ...
Page 263: ...Chapter 15 Appendix ...
Page 344: ...15 82 15 7 ASCII Codes ...
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