Mitsubishi FX3U-64CCL User Manual Download Page 3

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(1)

Before installation, operation, maintenance or inspection of this product, thoroughly read through and
understand this manual and the associated manuals. Also, take care to handle the module properly and
safely.

This manual classifies the safety precautions into two categories:

and

Depending on the circumstances, procedures indicated by

may also cause severe injury. In

any case, it is important to follow all usage directions. Store this manual in a safe place so that it can be taken
out and read whenever necessary. Always forward it to the end user.

1. DESIGN PRECAUTIONS

Indicates that incorrect handling may cause hazardous conditions, resulting in death or severe
injury.

Indicates that incorrect handling may cause hazardous conditions, resulting in medium or slight
personal injury or physical damage.

Reference

•

For the status of each station when the main unit stops calculation or when a communication error occurs in the
data link, thoroughly read the description of data link processing time in the CC-Link master module manual.
Construct an interlock circuit in the sequence program using the communication status information (BFM, SB, SW)
so that the system always works conservatively.
Erroneous outputs and malfunctions may cause accidents.
1) Setting to hold or clear the input information against data link error.

Remote outputs (RY) and remote registers (RWw) are held or cleared in accordance with the setting of BFM
#32.
0 (default): Data prior to the error is held.
Other than 0: Data prior to the error is cleared.

2) Setting to hold or clear the data against a stop in the main unit.

Remote inputs (RX) and remote registers (RWr) are held or cleared in accordance with the setting of BFM #33.
0 (default): Data prior to the stop is held.
Other than 0: Data prior to the stop is cleared.

•

When executing control (data changes) to an operating PLC, construct an interlock circuit in the sequence program
so that the entire system operates conservatively.
In addition, when executing control such as program changes and operation status changes (status control) to an
operating PLC, thoroughly read the manual and sufficiently confirm safety in advance.
Especially in control from external equipment to a PLC in a remote place, problems in the PLC may not be able to
be handled promptly due to abnormality in data transfer.
Construct an interlock circuit in the sequence program. At the same time, determine the actions in the system
between the external equipment and the PLC (Master station contains) for protection against abnormalities in data
transfer.

•

Make sure to include the following safety circuits outside the PLC to ensure safe system operation even during
external power supply problems or PLC failure.
Otherwise, malfunctions may cause serious accidents.
1) Above all, the following components should be included: an emergency stop circuit, a protection circuit, an

interlock circuit for opposite movements (such as normal vs. reverse rotation), and an interlock circuit (to prevent
damage to the equipment at the upper and lower positioning limits).

2) Note that when the PLC main unit detects an error during self diagnosis, such as a watchdog timer error, all

outputs are turned off. Also, when an error that cannot be detected by the PLC main unit occurs in an input/
output control block, output control may be disabled.
External circuits and mechanisms should be designed to ensure safe machinery operation in such cases.

Reference

•

Observe the following items. Failure to do so may cause incorrect data-writing through noise to the PLC and result
in PLC failure, machine damage or other accident.
1) Do not bundle the control line together with or lay it close to the main circuit or power line. As a guideline, lay the

control line at least 100mm (3.94") or more away from the main circuit or power line.
Noise may cause malfunctions.

2) Ground the shield wire or shield of a shielded cable. Do not use common grounding with heavy electrical

systems (refer to Subsection 5.1.2).

•

Do not apply excessive pressure to the power supply terminal block or CC-Link connection terminal block.
Excessive pressure may cause damage or error.

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Safety Precautions

(Read these precautions before using.)