Schneider 140CPS11100 | Modicon Quantum 115/230 VAC Power Supply, 3 A Standalone

Description

Key Technical Specifications

Product Introduction

When a Modicon Quantum rack loses power, the first suspect is usually the incoming AC supply or a tripped breaker. But sometimes the AC is healthy, the breaker is closed, and the rack is still dead. That is when the 140CPS11100 earns its keep — or reveals its failure.

The Schneider Electric 140CPS11100 is the standalone AC power supply for the Modicon Quantum PLC platform. It accepts 115 or 230 VAC and converts it to a regulated 5.1 VDC that feeds the backplane bus, powering the CPU, communication modules, and I/O modules installed in the rack. It does not power field devices — sensors and actuators get their 24 VDC from separate sources or from dedicated I/O power supplies. Its job is purely internal: keep the rack alive.

With a 3 A output, the 140CPS11100 is sized for smaller or medium-density Quantum racks. Larger configurations with many I/O modules typically require the higher-capacity summable (140CPS11420, 11 A) or redundant (140CPS12420, 11 A) variants. The 140CPS11100 cannot be paralleled for current sharing — it is a standalone unit.

Bottom line: if your Quantum rack has AC at the terminals but no PWR OK LED and no backplane activity, the 140CPS11100 is the first module to test. For legacy Quantum installations that cannot be migrated overnight, a tested surplus unit is often the fastest path to restoration.

Schneider 140CPS11100

QA/QC Transparency SOP

1. Intake & Origin Verification
Verify the full model number 140CPS11100 on the front label. Inspect the AC input terminals for corrosion or burn marks, the backplane connector for bent pins, and the enclosure for signs of overheating. Confirm it is the standalone 3 A variant, not the summable 140CPS11420 or redundant 140CPS12420.

2. Live Functional Testing
Install the module in a verified Modicon Quantum backplane (e.g., 140XBP series). Apply 115 VAC or 230 VAC to the AC input terminals with proper PE grounding. Verify the green PWR OK LED illuminates.

3. Electrical Parameter Tests
Use a Fluke 115 or equivalent multimeter to measure the 5.1 VDC backplane output at the module terminals and at the CPU slot. Verify output is within specification under no-load and loaded conditions. Check for shorts on the output side. Measure input current draw and confirm it is within expected range for the applied voltage.

4. Protection Circuit Verification
Verify that the internal overvoltage and overcurrent protection circuits are functional by monitoring output behavior during controlled test conditions. Confirm the module shuts down cleanly on fault and recovers when power is cycled.

5. Final QC & Anti-Static Packaging
Document test results, model number, input voltage used, output voltage measured, and LED status. Seal in ESD-safe packaging with terminal protection. Include a test certificate referencing the backplane model and load configuration used during testing.

Field Engineer Gotchas

Standalone vs. Summable vs. Redundant
The 140CPS11100 is a standalone 3 A supply. It cannot be paralleled with another 140CPS11100 for current sharing. If your rack draws more than 3 A on the 5 VDC bus, you need the summable 140CPS11420 or redundant 140CPS12420. Mixing these variants in the same rack requires careful configuration.

5 VDC Backplane Power Only
The 140CPS11100 supplies only the 5.1 VDC backplane bus. It does not provide 24 VDC for field sensors or actuators. If your I/O points are dead but the CPU is running, the problem is almost certainly not this power supply — check the field power distribution instead.

Input Voltage Selection
The module auto-ranges between 115 VAC and 230 VAC — there is no voltage selection switch. However, verify that the incoming AC is within the specified range (93–138 VAC or 170–276 VAC). A marginal supply at 100 VAC on a 115 VAC circuit may cause intermittent dropouts.

PWR OK LED Interpretation
A solid green PWR OK LED means the 5.1 VDC backplane bus is powered and within tolerance. If the LED is off but AC is present at the terminals, the module has likely failed internally. If the LED is flashing or dim, check for an overloaded backplane — too many modules drawing current beyond the 3 A limit.

Backplane Slot Position
In most Quantum rack configurations, the power supply occupies the leftmost slot (Slot 0). Installing it in the wrong slot will prevent the rack from powering up. Verify the rack documentation for your specific 140XBP backplane model.

Legacy Product Status
The Modicon Quantum platform is a mature/legacy system. The 140CPS11100 is no longer in active production and is sourced primarily through surplus and refurbished channels. For new projects, consider migrating to the Modicon M580 or M340 platform.

Schneider 140CPS11100

Application Scenarios

Legacy Process Control Systems
Many water/wastewater treatment plants, power generation facilities, and chemical processing sites still run Modicon Quantum PLCs installed in the 1990s and 2000s. The 140CPS11100 keeps these racks powered when original units fail.

Small to Medium Quantum Racks
With a 3 A output, the 140CPS11100 is well-suited for compact Quantum racks with a CPU, one or two communication modules, and a modest I/O count. Larger racks should use the 11 A summable or redundant variants.

Spare Parts Inventory
For facilities running multiple Quantum racks, keeping a tested 140CPS11100 in spare parts inventory minimizes downtime. A failed power supply can take an entire rack offline in seconds.

Case Study (Anonymized):
A municipal water treatment plant reported that one of its Modicon Quantum racks had gone dark overnight. The incoming 120 VAC was confirmed present at the power supply terminals, but the PWR OK LED was off and the CPU was unresponsive. The maintenance team checked the AC breaker, verified wiring, and even swapped the CPU — all without success. Replacing the 140CPS11100 with a tested surplus unit restored the rack immediately. Root cause: aged electrolytic capacitors in the DC/DC converter stage had failed after 18 years of continuous operation. The lesson: on legacy Quantum systems, the power supply is often the weakest link, not the CPU.

FAQ

Is the 140CPS11100 still in production?
No. The Modicon Quantum platform is a legacy system, and the 140CPS11100 is no longer in active production. Units are available through surplus and refurbished channels. For new installations, consider the Modicon M580 or M340 platform.

What is the difference between 140CPS11100 and 140CPS11420?
The 140CPS11100 is a standalone 3 A power supply. The 140CPS11420 is a summable 11 A power supply that can be paralleled with other summable units for higher backplane current capacity. They are not interchangeable without verifying the rack power budget.

Does the 140CPS11100 provide 24 VDC for field devices?
No. It provides only 5.1 VDC to the Quantum backplane bus. Field devices (sensors, actuators, relays) require separate 24 VDC power distribution.

Can I use 140CPS11100 with a 140XBP backplane?
Yes. The 140CPS11100 is designed for Modicon Quantum 140XBP series backplanes. It installs in the dedicated power supply slot, typically the leftmost position.

What does a flashing PWR OK LED mean?
The official documentation describes a solid green PWR OK LED for normal operation. A flashing or absent LED typically indicates a fault — either insufficient AC input, an overloaded backplane, or an internal module failure. Measure the 5.1 VDC output to confirm.

Can I hot-swap the 140CPS11100?
Modicon Quantum power supplies are generally designed for hot-swap capability, but always follow site-specific lockout/tagout procedures and verify with the official Schneider Electric product manual before removing or inserting a live power supply.

What fuse rating should I use on the AC input?
The associated fuse rating is 1.5 A slow-blow. Use this rating on the AC input circuit to provide proper overcurrent protection without nuisance tripping.