TM3DI32K Overview
When expanding the I/O capacity of your Modicon M221, M241, M251, or M262 controller, the Schneider Electric TM3DI32K discrete input module delivers a cost-effective and space-saving solution. This 32-point module accepts 24V DC signals and supports both sink and source wiring, giving you the flexibility to match existing field wiring without extra adapters. With a compact 33.5 mm width, the TM3DI32K maximizes panel density, reducing enclosure size and per-point cost.

Key Technical Specifications
The TM3DI32K is engineered for reliable, high-density digital sensing. Below are the critical parameters that define its performance and installation requirements:
| Parameter | Value |
|———–|——-|
| Inputs | 32 (IEC 61131-2 Type 1) |
| Input Voltage | 24V DC |
| Input Current | 5 mA per input |
| Logic Type | Sink or Source (positive/negative) |
| On-state Voltage | 15…28.8V |
| Off-state Voltage | 0…5V |
| On-state Current | ≥2.5 mA |
| Off-state Current | ≤1 mA |
| Input Impedance | 4.4 kΩ |
| Response Time | 4 ms on / 4 ms off |
| Connection | HE-10 connector |
| Isolation | 500V AC (input to logic) |
| Power Consumption | 65 mA @5V DC (on); 5 mA @5V DC (off) |
| Operating Temp | -10…55°C (horizontal), -10…35°C (vertical) |
| Dimensions (H×W×D) | 90 × 33.5 × 81.3 mm |
| Weight | 0.1 kg |
These specifications show a module that balances speed, power efficiency, and environmental tolerance. The 4ms response time suits fast counting or position sensing, while the low 5 mA input current reduces control transformer loading.
Real-World Applications
Packaging Machinery: In a bottle-filling line, the TM3DI32K reads 32 proximity sensors that detect bottle presence and fill levels. Its fast 4ms update ensures accurate timing for valve actuation, minimizing product waste and rework costs.
Material Handling: For a conveyor sortation system, the module monitors photoelectric sensors across multiple lanes. The sink/source flexibility lets you connect NPN or PNP sensors directly, eliminating the need for signal converters—saving hardware cost and installation time.
HVAC Control: In a building management retrofit, the TM3DI32K replaces older, higher-power input cards. The 5 mA per input reduces heat generation inside the control panel, extending the life of adjacent electronics and lowering cooling requirements.

Installation & Setup Guidance
Mount the TM3DI32K on a standard 35 mm DIN rail (TH35-15 or TH35-7.5) or on a panel using a fixing kit. For reliable operation, keep unshielded input wiring shorter than 30 meters—this prevents noise pickup that could cause false triggers. Use the HE-10 connector for all input wiring; ensure the connector is fully seated to avoid intermittent signals. The module supports both sink and source wiring, so verify your sensor type and set the common wiring accordingly. Because inputs are non-isolated from each other, group wires by voltage potential to avoid cross-talk.
Maintenance & Reliability
With no moving parts, the TM3DI32K requires minimal upkeep. However, periodic inspection of the HE-10 connector and wiring terminals is recommended to catch loose connections before they cause downtime. The module operates reliably in temperatures up to 55°C when mounted horizontally, but if you install it vertically, derate to 35°C—this prevents overheating in confined cabinets. The IP20 rating (with protective cover) means you should keep the cover on in dusty environments. Following these simple steps maximizes uptime and avoids costly emergency repairs.
Compatibility & Integration
The TM3DI32K is designed for Modicon M221, M241, M251, and M262 controllers. It connects via the bus connector, drawing power from the backplane—no separate supply needed. The module is CE, CULus, UKCA, RCM, and EAC certified, ensuring compliance for global installations. It also meets marine specifications (LR, ABS, DNV, GL), making it suitable for shipboard automation. When integrating, verify that your PLC firmware supports the module; refer to the controller’s I/O configuration guide for channel mapping.
Selection & Purchasing Advice
Before ordering, confirm that your PLC model is in the compatible list (M221/M241/M251/M262) and that your input voltage is 24V DC. The TM3DI32K uses a HE-10 connector, so you may need a pre-wired cable or a field-wireable HE-10 plug—check your existing spares. For high-density applications, this module offers 32 points in a 33.5 mm width, which can reduce the number of I/O cards required, lowering overall system cost.
SpareTechPLC stocks the TM3DI32K and can advise on availability and lifecycle status. Contact our team for a quote or to discuss replacement options if your system uses older, discontinued input modules.
Frequently Asked Questions
Can the TM3DI32K accept both NPN and PNP sensors?
Yes, the module supports sink (NPN) and source (PNP) wiring, so you can connect either type without additional converters.
What is the maximum cable length for the inputs?
For unshielded cable, keep the distance under 30 meters to ensure reliable signal detection. For longer runs, use shielded cable or consider remote I/O.
Does the TM3DI32K require an external power supply?
No, it draws power from the PLC backplane via the bus connector. It consumes 65 mA at 5V DC when all inputs are on.
What is the response time of the inputs?
Both turn-on and turn-off times are 4 ms, which is suitable for most industrial sensing applications, including counting and position detection.
Is the TM3DI32K compatible with Modicon M580 or M340?
No, it is specifically designed for Modicon M221, M241, M251, and M262 controllers. For other platforms, consult SpareTechPLC for compatible I/O modules.