TM3DQ8T | Schneider Electric 8-Ch Transistor Output Module

What Is the TM3DQ8T Digital Output Module?

The Schneider Electric TM3DQ8T is an 8-channel digital output expansion module from the Modicon TM3 series. It delivers 24 Vdc transistor outputs in source (PNP) configuration, with a maximum of 0.5 A per channel. Consequently, machine builders gain fast, repeatable switching for solenoids, relays, indicator lamps and small contactors. Each module occupies a compact 27.4 mm width on the controller rail, so panel space stays efficient.

Because the module communicates through the TM3 bus, it draws its supply directly from the host platform. Bus current consumption is 20 mA at 5 V DC with all outputs on, and 5 mA with all outputs off. This keeps total system loading predictable during panel design.

TM3DQ8T Key Specifications

• Output type: 24 Vdc transistor, source (PNP)
• Channels: 8 digital outputs
• Output current: 0.5 A per channel (max)
• Isolation: 500 V AC between output and internal logic
• Response time: 450 µs max. (turn on/off)
• Diagnostics: Module status, bus status, short-circuit and overload protection
• Supply voltage: 24 Vdc via the TM3 bus
• Operating temperature: 0...+55 °C
• Protection rating: IP20
• Dimensions (H×W×D): 90 × 27.4 × 84.6 mm
• Weight: 0.1 kg

Notably, the 450 µs response time suits high-cycle sorting, packaging and labeling tasks where output latency directly affects throughput. The 500 V AC isolation barrier protects internal logic from field transients, although there is no isolation between individual channels. Therefore, all outputs share a common reference, which simplifies wiring for grouped loads.

Compatibility and Integration

The TM3DQ8T operates with Modicon M221, M241, M251 and M262 controllers. It connects through the TM3 expansion bus, so no separate fieldbus gateway is required for basic I/O expansion. For distributed architectures, confirm gateway and cabling requirements with the supplier before commissioning. Wiring uses a removable screw terminal block at 5.08 mm pitch, which speeds replacement without disturbing adjacent wiring.

Typical Applications

In packaging machinery, the module drives pneumatic valve islands and status lamps. In material handling, it actuates diverter solenoids and motor starters. Because each channel handles 0.5 A, small contactors and pilot relays connect directly without interposing relays. Meanwhile, the short-circuit and overload diagnostics help maintenance teams isolate faults quickly. For process skids, the wide 0...+55 °C operating range supports non-conditioned cabinets.

Installation and Maintenance Notes

Mount the module on the controller rail and secure the removable terminal block after wiring. Verify 24 Vdc supply polarity before energizing, since source (PNP) outputs require the correct common reference. Periodically inspect terminals for loosening and confirm the IP20 enclosure remains free of conductive dust. The module reports status through module and bus LEDs, which simplifies fault finding during scheduled checks.