Mitsubishi Q Series NZ | Q38B Q65B Q61P QX40 QJ71 MELSEC Q

Mitsubishi MELSEC Q Series

Mitsubishi / MELSEC Q series

A Q55B and a Q65B are both five-slot extension bases. The Q55B needs no power supply module and the Q65B requires one. One character, and it decides whether the base works on its own.

Q series is the Mitsubishi modular platform and still runs a great deal of New Zealand plant, particularly on imported machinery.

Reading a base unit number

The most systematic part of the Q range, and the most commonly misordered.

Prefix	Type	Power supply module
Q3xB	Main base	Required
Q5xB	Extension base	Not required
Q6xB	Extension base	Required

The digits after that are the slot count.

Slots	Main base	Extension, no PSU	Extension, PSU required
2		Q52B
3	Q33B		Q63B
5	Q35B	Q55B	Q65B
8	Q38B		Q68B
12	Q312B		Q612B

So the number tells you both the role and the slot count. A Q68B is an eight-slot extension needing its own supply; a Q38B is an eight-slot main base.

Mounting widths

Useful when checking whether a larger base will fit.

Base	Width
Q33B	189 mm
Q35B	245 mm
Q38B	328 mm
Q312B	439 mm
Q52B	106 mm
Q55B	189 mm

All are 98 mm high.

The suffix letters

Suffix	Meaning	Examples
D	High speed, multi-CPU	Q35DB, Q38DB, Q312DB
R	Redundant	Q38RB, Q68RB, Q65WRB
S	Slim	Q32SB, Q33SB, Q35SB
L	Variant	Q35BL, Q38BL, Q55BL, Q65BL

The slim base cannot be extended

A hard limitation worth knowing before specifying one.

A slim type main base unit cannot be connected to an extension base.

Slim base	Slots	Width
Q32SB	2	114 mm
Q33SB	3	142 mm
Q35SB	5	197.5 mm

So a machine on a slim base that has run out of slots needs a different base, not an extension. That is a rebuild rather than an addition.

Slim bases also do not support the process CPU.

The D base and multiple CPUs

High speed base units use a secondary inter-CPU bus to share more data at faster speeds between up to four CPUs.

Older Q series CPUs can be used on a D base but will not gain performance from it. So fitting a D base to an existing single-CPU system achieves nothing.

The reverse matters more: a multi-CPU system built around a D base cannot be moved to a standard base without losing the inter-CPU bus.

A and AnS modules need a QA base

The migration path, and the reason some Q systems look mixed.

Standard Q bases take Q series I/O, intelligent function and network modules only. Mitsubishi is explicit that A and AnS series modules cannot be loaded on them.

Base	Takes	Power supply
QA1S51B	AnS series modules	No AnS PSU needed
QA1S65B, QA1S68B	AnS series modules	AnS series PSU required
QA65B, QA68B	A series modules	A series PSU required
QA6ADP with A5B or A6B	A series modules via adapter	Varies

So a plant moving from A series to Q can keep its existing A and AnS modules by running them on QA bases off a Q CPU.

That turns a full replacement into a staged one, and it is the same pattern as the RQ bases on iQ-R and the BK1120 on our Beckhoff page.

Note the power supply follows the module generation, not the CPU. A QA65B needs an A series supply, not a Q one.

Power supply modules

Module	Input	Output
Q61P	100 to 240 V AC	5 V DC, 6 A
Q61P-A1	100 to 120 V AC	5 V DC
Q61P-A2	200 to 240 V AC	5 V DC
Q62P	100 to 240 V AC	5 V DC 3 A plus 24 V DC 0.6 A
Q63P	24 V DC	5 V DC, 6 A
Q64P	100 to 120 or 200 to 240 V AC	5 V DC, 8.5 A
Q61SP	AC	Slim base version
Q63RP, Q64RP		Redundant

Three that catch people

The Q61P replaced both the Q61P-A1 and Q61P-A2, combining their input ranges. So a Q61P is a valid replacement for either; the reverse is not true, because the A1 is 100 to 120 V only.

The Q62P is the one with a 24 V output. If a panel takes its sensor supply from the PLC power module, that is why. A Q61P has no 24 V output and swapping one in leaves the sensors dead.

The Q63P is DC input. On a 24 V panel that is the correct module, and an AC unit will not work.

Extension cables

Cable	Length
QC05B	0.45 m
QC06B	0.6 m
QC12B	1.2 m
QC30B	3 m
QC50B	5 m
QC100B	10 m

There is a limit on total extension length across the whole system, not just per cable. So a long run to a remote base plus several short hops can exceed it even when each cable is within spec.

Tell us the layout and we will flag it.

The Q00J is an all-in-one

Worth knowing because it changes what you are ordering.

The Q00JCPU and Q00UJCPU integrate the power supply, CPU and a five-slot main base into a single unit. No separate base and no separate supply.

CPU	Main base	I/O points
Q00JCPU	Integrated, 5 slots	256
Q00CPU, Q01CPU	Required separately	1024

So a Q00J failure is a bigger replacement than a Q00 failure, because the base and supply go with it.

Extension bases can still be connected to a Q00J.

The CPU families

Family	Range
Basic	Q00J, Q00, Q01
High performance	Q02, Q02H through Q25H
Universal	Q02U through Q26UD(E)H
Process	Q02PH through Q25PH
Redundant	Q12PRHCPU, Q25PRHCPU
Motion	Q172, Q173 series

The number is the program capacity, so a Q25 holds considerably more than a Q02.

The redundant CPUs carry 124k steps on the Q12PRH and 252k steps on the Q25PRH, both at 4096 I/O points.

The E is Ethernet

A Q03UDE has built-in Ethernet and a Q03UD does not. One character, and on a networked machine it is the whole difference.

Send the CPU designation exactly as printed on the module.

Batteries and memory cards

Part	Notes
Q6BAT	Standard memory cell
Q7BAT	Large capacity
Q7BAT-SET	Large capacity with holder

SRAM cards need the battery, flash cards do not

Card	Type	Battery dependent
Q2MEM-1MBS, Q2MEM-2MBS	SRAM	Yes
Q2MEM-2MBF, Q2MEM-4MBF	Flash	No

The S is SRAM and the F is flash. One character, and it decides whether the contents survive a flat battery.

So a Q with an SRAM card and an unattended battery is carrying a real risk. If a battery warning has been ignored on such a system, that is worth acting on.

Batteries are cheap and a consumable. Order them ahead.

DIN rail adapters are base-specific

Q bases mount on screws by default. DIN mounting needs an adapter, and it is matched to the base size.

Adapter	Suits
Q6DIN1	Q38B, Q312B, Q68B, Q612B
Q6DIN2	Q35B, Q65B, Q00JCPU, Q00UJCPU
Q6DIN3	Q33B, Q52B, Q55B, Q63B

The adapter is a separate part and it is easy to leave off an order. Tell us how the base mounts.

I/O modules

Prefix	Type
QX	Digital input. QX40, QX41, QX80
QY	Digital output. QY10, QY40P, QY41P, QY70, QY71, QY80
QX41Y41P	Mixed input and output
Q6xAD, Q6xDA	Analogue
QJ71	Network modules. QJ71E71 Ethernet, QJ71BR11 and QJ71LP21 MELSECNET
QJ72	Remote I/O network modules
QD	Positioning and counter modules

QJ71 is master or local and QJ72 is the remote station. One digit, and they sit at opposite ends of the network.

Connectors and terminal blocks

High-density modules use a 40-pin connector, and the connector is a separate part in several forms.

Part	Type
A6CON1	Soldering
A6CON2	Crimp contact
A6CON3	IDC
A6CON4	Soldering, inclined insertion
Q6TE-18S	Spring clamp terminal block
Q6TA32	IDC terminal block adapter, with Q6TA32-TOL tool

A 40-pin module arrives without a connector. If you are replacing a high-density module and the existing connector is sound, you do not need another. On a new installation you do, and you need the right termination type.

Programming

The QC30R2 cable connects a PC to the CPU over RS-232.

Software	Covers
GX Developer	Q series, version 7 or later for basic model QCPU
GX Works2	Q series and FX
GX Works3	iQ-R and FX5. Not Q

GX Works3 does not open a Q series project. A site that has moved to the current tooling may find it cannot open its own older programs.

What to send us

The full model number of whatever failed.

The base unit number. It tells us the slot count and whether a supply is needed.

The power supply module, particularly whether it has a 24 V output.

Whether the system has QA bases, since A and AnS modules need them.

Whether the base is DIN mounted.

A photo of the rack. Q modules are clearly labelled and one photo usually identifies the lot.

What we can supply

Q series across the range. CPUs, base units, power supplies, QX and QY I/O, analogue, QJ71 network modules, positioning modules, extension cables, batteries, memory cards, DIN adapters and connectors.

QA bases and A and AnS series modules, for mixed systems.

MELSEC iQ-R, including the RQ extension bases that let Q modules run on an iQ-R system.

Much of the Q range is discontinued, so this is new old stock, surplus and tested used.

We buy Mitsubishi Q

Q series modules hold real value because a like-for-like replacement avoids both a program conversion and a rack rebuild.

If you are migrating a plant to iQ-R, do not scrap the Q modules. They are worth considerably more to another plant, and CPUs and network modules most of all. See Sell To Us.

Send us your part numbers

The base number tells us the slot count and whether it needs its own supply. Q55B and Q65B are not the same thing. Quotes in NZD including GST.

Request a quote

Industech is an independent supplier of new, surplus and used industrial automation equipment. We are not an authorised distributor of, approved by, sanctioned by, or affiliated with Mitsubishi Electric. MELSEC, MELSECNET, CC-Link, GX Developer and GX Works are trademarks of Mitsubishi Electric Corporation. All trademarks, brand names and part numbers are the property of their respective owners and are used here for identification purposes only.