Schneider Electric 140CPS12400 – 24 VDC Power Supply for Modicon Quantum Racks

The 140CPS12400 is a Modicon Quantum power supply module designed to feed stable backplane power to 140XBP-series racks. It runs on a 24 VDC input and, in most cases, is a straightforward drop-in for standard Quantum control cabinets where DC plant power is already available.

From my experience, this model is chosen when teams want predictable uptime, clear status indication, and a proven form factor without reworking existing panels. It’s a practical choice for sustaining mature Quantum systems in process, utility, and manufacturing environments.

• 24 VDC input range – Typically accepts 24 VDC nominal (industry-standard DC bus in many plants), which helps simplify cabinet power distribution.

• Backplane power for Quantum – Provides regulated 5 VDC to the Modicon Quantum backplane for CPUs, comms, and I/O modules.

• Status LEDs – Clear front-panel indicators for power conditions; you can quickly see if the rack power is healthy without tools.

• Protection built-in – Includes overcurrent and thermal protection to help safeguard both the power module and your rack electronics.

• Single-slot form factor – Installs in the left-most power-supply slot of 140XBP racks; no special brackets or adapters required.

• Service-friendly – Front-access terminals make wiring checks and replacements quicker during planned downtime.

You’ll typically see the 140CPS12400 supporting Quantum racks in:

• Process industries – Chemical, oil & gas, and refining sites that standardize on 24 VDC distribution for control cabinets.

• Water & wastewater – Plants maintaining Quantum-based SCADA and remote I/O, where stable rack power is non‑negotiable.

• Discrete manufacturing – Packaging lines and material handling systems keeping a legacy Quantum backbone in service.

• Power & utilities – Balance-of-plant controls where DC-backed panels are the norm for reliability reasons.

• Reliability under load – It seems to be quite tolerant of typical plant voltage swings, keeping the backplane stable.

• Compatibility – Works with standard 140XBP racks and the broader Modicon Quantum ecosystem; no rewiring surprises.

• Lower retrofit effort – When you already have 24 VDC available, this avoids AC feed changes and extra hardware.

• Service continuity – A sensible spare for sustaining existing Quantum racks while planning longer-term migrations.

One thing I appreciate is how quickly maintenance teams can diagnose power states from the front LEDs. A maintenance lead recently mentioned they’ve run these in a dusty packaging hall for years with no unexplained dropouts—routine cleaning and proper grounding made the difference.

• Cabinet & mounting – Install the Quantum rack on a rigid panel in a clean, ventilated control cabinet. Keep ambient within the specified temperature range.

• Wiring – Use appropriately rated 24 VDC supply wiring with proper overcurrent protection. Tighten terminal screws to the recommended torque and connect protective earth to the cabinet ground bus.

• Clearance & airflow – Provide space for convection; avoid bundling high-current motor wiring adjacent to the rack to reduce noise coupling.

• Load planning – Verify the total module load against the PSU capability; in many cases, a mid-sized rack is fine, but high-density I/O may require load balancing across racks.

• Routine checks – Inspect terminals for looseness, clean dust from vents, and review LED status at shift handovers. Replace if thermal derating or nuisance trips are observed.

• Certifications – CE and UL/cUL; RoHS-compliant design is typical for this series.

• Warranty – Manufacturer warranty typically 18 months from shipment (region-dependent).

If you’re matching this against an installed rack, a quick check of the rack model (140XBPxxxxx) and the available 24 VDC feed usually confirms fit. If you’d like, I can help estimate backplane load based on your CPU, comms, and I/O mix to ensure the 140CPS12400 is comfortably sized.