What it is, what it does
The Schneider Electric TM5SDM8DTS is a discrete I/O module in the Modicon TM5 family — 4 sink digital inputs and 4 source transistor outputs at 24 V DC on a 12.5 mm DIN-rail slice. It runs on the TM5 bus with 2 mA draw at 5 V DC and 62.5 mA at 24 V DC from the backplane, dissipating 1.51 W — power-budget that slot before you stack it next to a heavy analog slice. One green LED indicates power supply status, one red LED indicates power supply status, and 8 LEDs map per-channel input/output state for point-level fault isolation without an HMI.
Per-channel current is 0.1 A with a 0.4 A peak and a 0.4 A common ceiling, and the output drops <0.9 V at 0.1 A — sized for indicator lamps, solenoid valves and small relay coils rather than motor contactor coils. Off-state leakage stays at 25 µA at 24 V DC, so the sink input does not see a phantom ON through a long field run. Inputs accept 24 V DC within 20.4–28.8 V; outputs switch the same 24 V DC window. Hardware switching is rated at 2 µs, which carries fast event tasks but is not a high-speed counter slice. Voltage state windows follow IEC 61131-2 Type 1 sink input / positive-logic source output — the standard mix for European panels.
Mechanical and environment
Footprint is 12.5 mm wide by 99 mm tall by 75 mm deep on DIN rail, IP20 with pollution degree 2 — typical for a closed control cabinet, not a field-mounted enclosure. Electrical connection is single-wire per point, which keeps the wiring diagram clean but means return conductors land on the TM5 common terminal — not a 3-wire sensor-friendly slice. Operating range is -10…60 °C horizontal installation with derating and -10…50 °C vertical; storage spans -40…70 °C. Altitude is rated to 2000 m and humidity 5…95 % non-condensing. Shock is 15 gn for 11 ms and vibration 1 gn at 8.4…150 Hz on DIN rail (3.5 mm at 5…8.4 Hz), so it rides normal industrial cabinet vibration without complaint.
Compliance and EMC envelope
Agency standards carried are UL 508, CSA C22.2 No 142 and IEC 61131-2 — the usual North American and IEC industrial control package, no extra approvals layered on for hazardous locations. EMC immunity covers the full industrial stack: 4 kV contact / 8 kV air ESD, 10 V/m radiated 80…2000 MHz, 1 kV on I/O and shielded cable plus 2 kV on power lines for fast transient/burst, 0.5 kV differential / 1 kV common mode surge, and conducted RF per IEC 61000-4-6, with emissions to CISPR 11.
For a BOM line that needs this exact 4DI/4DO 24 V DC source/sink mix, the spec is stable: the part sits on the standard TM5 compact I/O footprint with the standard bus interface, so there is no current substitute to chase and no firmware-version trap to set up.