Replacement Selection Points - Mitsubishi Electric MELSEC-A Series Manual

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INTRODUCTION

1.1.3 Replacement selection points

To replace any one stations in the existing MELSECNET(II) with the QCPU or to add the QCPU in the
system, replace the network used with the MELSECNET/10 simultaneously.
(1) Replacing the existing A/AnS/QnA/QnASCPU with the QCPU
This section describes the methods for replacing the network used with the MELSECNET/10
simultaneously and replacing any one stations in the existing MELSECNET(II) with the QCPU.
Existing network configuration
A2
MELSECNET(II)
A3
Item
Cable
laying
Cost
Network module
Only first half set
in second tier
system
Modification
Latter half set in
on software
second tier system
Three-tier system
Extensibility
*1 Twisted pair cables can be used by replacing the remote I/O station with a normal station and configuring a PLC to PLC
network.
A1
A6
A5
A4
Advantage
• Laying change is not required since the existing network
Optical cable can be used without change.
cable • Due to restrictions on station-to-station distance in some
cable types, check the cable type if the distance is long.
• Change from coaxial loop to coaxial bus is required.
Coaxial • One side of the existing coaxial cable can be utilized.
loop • Due to restrictions on overall cable distance, if the distance
is long, repeater module is required.
• Since the twisted pair cables can be used for the
MELSECNET/H only, all stations must be replaced with
QCPU.
Twisted
• When replacing the stations with QCPU step-by-step or
pair
replacing with the remote I/O network, change the twisted
pair cables to coaxial bus cables. (The twisted pair cables
cannot be used for the remote I/O network.)
• All the existing stations are required to be replaced with the
MELSECNET/10 modules.
• Setting made to the existing network parameter can be
utilized without change.
• Station-specific parameter setting is required.
• If the AnN, AnA, or AnSCPU (excluding AnUS(H)CPU)
exists, newly set network parameters and modify the
program.
• Since the second tier and the third tier is separate network,
reviewing the network parameter and program is required
• By simultaneous replacement to the MELSECNET/10,
replacing arbitrary station with the QCPU is possible.
• If modification on software is required, modifying it at
replacement of the first module allows omitting modification
to the second module or later.
Replaced network configuration
A1
A2 A6
MELSECNET/10
A3 Q5
A4
: No restrictions, : Some restrictions,
Outline
Replaced QCPU
: Many restrictions
Reference
Section 2.2.1
(1)
Section 2.2.1
(2)
Section 2.2.1
(3)
*1
-
Section 2.5.1
(1)
Section 2.5.1
(1)
Section 2.5.3,
Section 2.5.4
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