Obsolescence guides · Modicon Quantum (140) catalogue
Modicon Quantum end of commercialisation
Schneider Electric Modicon Quantum (140) · 1995–2028 announced EOL
Where the platform stands
Schneider Electric has announced the end of commercialisation for the Modicon Quantum platform. The announcement itself changes the market: every site running Quantum is now competing for the same finite pool of spares, and the pool stops being replenished.
Why spares are hard to find
Quantum is concentrated in water treatment, oil and gas, and infrastructure — long-life assets with long procurement cycles and little appetite for a control system rebuild. Demand for 140 CPU and 140 I/O modules is rising against a fixed supply, which is the textbook setup for prices climbing year on year.
What actually fails first
From what comes through a repair bench on control gear of this age. Worth reading before you buy a replacement — two of these are cheap fixes that get misdiagnosed as a failed module.
Electrolytics dry out over 15–25 years, especially in warm panels. The supply does not fail cleanly — it sags under load, which presents as random processor faults and I/O dropouts that look like a software problem. If an old rack is behaving strangely, suspect the supply before the program.
Processors of this era keep the program and retentive data in volatile memory backed by a lithium cell. The cell lasts years, not decades — and when it dies the program goes with it on the next power cycle. Many "dead processor" calls are a flat battery and a lost program. Keep a current backup of the program off the machine; it is the cheapest insurance in the panel.
Relay outputs are rated in operations, not years. A contact switching an inductive load every few seconds reaches end of life long before the rest of the module. Symptoms are intermittent: the output is commanded and the device sometimes does not move.
The migration route, and what it really costs
Modicon M580 is the declared successor, and Schneider position it as a modernisation path that can retain Quantum remote I/O drops — which, if it applies to your architecture, is a very large saving over a full rebuild. Worth a serious conversation with an integrator before buying more Quantum spares, because the economics may already favour moving.
The case for keeping it running
Spares worth holding
If you are keeping the platform running, these are the items whose failure stops production — hold them rather than waiting to need them.
All 27 Modicon Quantum (140) parts we source →
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Forge Horizons is an independent sourcing merchant and not an authorised distributor or agent of Schneider Electric. This page is general guidance from our own sourcing experience, not engineering advice — confirm anything safety-related with the manufacturer or your integrator.