Specifications
6
1. Introduction
1. Introduction
1.1 Outline
Thank you very much for your continued use of Mitsubishi PLCs.
It may be time to renew your PLCs due to aging or deterioration over years of use, discontinued production
of products, or termination of service or repair term.
This manual describes the procedure of replacing your FX (FX
2N, FX2NC) series PLCs with FX3 series
PLCs.
1.1.1 Replacement models
To replace FX (FX2N, FX2NC) series PLCs, a system conguration composed of FX3 series models is
recommended.
Recommended replacement models introduced in this manual are general representative models selected
based on the number of inputs and outputs, program capacity, and shapes of input and output terminals
(terminal blocks, connectors, etc.). Depending on actual usage, models other than the recommended ones
may be more suitable.
1.1.2 Necessity of renewal
(1) Service life
Our products are composed of very reliable parts, but inside each product is a great number of
electronic components.
When all components function normally, optimal function and performance of the product will be
realized.
However, some parts (electrolytic capacitors, relays, switches and others) have a limited service life.
The length of the service life varies depending on the part, and if used beyond the service life, optimal
operation can not be expected and troubles or failures may occur. Generally, the deterioration of
electronic components depends on the operating environment, and premature deterioration may occur if
used in hot environments, overloaded conditions, or if incorrectly installed or connected.
Deterioration of parts due to aging or environment may shorten the service life of the product, and
periodic renewal becomes necessary.
(2) Systematic and planned preventive maintenance
It can be difcult to dedicate resources for maintenance of systems that may still be functioning within
an acceptable range.
Conversely, poor maintenance may accelerate deterioration.
Once a problem occurs, it may take an increased amount of time for recovery, and losses incurred may
end up being signicantly greater than if preventative maintenance had been performed routinely.
Therefore, it is important to plan maintenance carefully by investigating the equipment, reading the
programs, preparing spare parts, and considering a renewal procedure.
Carefully planned maintenance and renewal should always be recommended.