When a Legacy Line Goes Down, Every Minute Counts
A production supervisor watches a packaging line stall because a 20-year-old Modicon TSX Micro PLC has a failed I/O base. The replacement must match the existing wiring, fit the same DIN rail, and survive the same washdown-adjacent humidity. The TSXDMZ28AR from Schneider Electric answers exactly that challenge. This discrete relay I/O base belongs to the Modicon TSX Micro automation platform. It packs 16 discrete inputs and 12 relay outputs into a single module. That density lets you restore a full machine section without adding rack space or rewiring field devices.
What Makes This Module a Drop-In Upgrade
Channel Count and Field Wiring
The module provides 16 screw terminal block inputs and 12 NO relay outputs. The inputs accept 100…120 V AC at 47…63 Hz. Each input draws 11 mA at 50 Hz or 13 mA at 60 Hz. Input voltage limits are >= 74 V at state 1 and < 20 V at state 0. Guaranteed current is <= 4 mA at state 0 and >= 6 mA at state 1. These thresholds tolerate the voltage sag common on long cable runs in older plants. The inputs also work with 2-wire proximity sensors, so you can keep existing sensor wiring intact.
Output Flexibility and Load Handling
Relay outputs switch 19…264 V AC or 10…34 V DC. Contact composition is NO. Power consumption ratings include 50 VA at 24 V AC-12 resistive and 220 VA at 220 V AC-12 resistive. Inductive loads are covered at 24 VA for 24 V AC-15 and 220 VA for 220 V AC-15. DC ratings reach 40 W at 24 V DC-12 resistive and 24 W at 24 V DC-13 inductive. That range lets one module drive solenoids, contactors, and indicator lamps without interposing relays.
Speed, Isolation, and Environmental Tolerance
Output response time is < 10 ms. Input response ranges from 11...18 ms at state 0 to state 1 at 50 Hz, and 11...24 ms at state 1 to state 0 at 50 Hz. Isolation between channels and logic is 500 V AC, with a 1500 V 1 s isolation voltage rating and insulation resistance >= 10 mOhm. The module operates from -25°C to +70°C and stores from -40°C to +85°C. Humidity tolerance is 5% to 95% non-condensing. Power consumption is just 3 W, with current consumption of 125 mA and power dissipation of 5.6 W.
Where the TSXDMZ28AR Fits Best
Replacing Obsolete I/O in Food and Beverage Plants
A bottling plant in a humid environment needs I/O that tolerates washdown humidity without condensation failures. The 5% to 95% non-condensing rating and -25°C to +70°C operating range suit this setting. The 28-channel density reduces cabinet footprint, which matters when floor space is tight.
Material Handling and Conveyor Control
A distribution center runs sortation conveyors with 24 V DC photoeyes and AC motor starters. The 16 AC inputs read photoeyes directly. The 12 relay outputs switch starter coils at 220 V AC. The < 10 ms output response keeps divert arms timed correctly at high line speeds.
Legacy TSX Micro PLC Retrofits
When a TSX Micro PLC rack loses an I/O base, the TSXDMZ28AR restores the exact channel mix the original machine used. The DIN rail mount and screw terminal blocks match the original installation method. This avoids rewiring field devices or modifying the control cabinet.
Installation and Commissioning Notes
Mount the module on DIN rail inside a protective enclosure. Verify that input voltage stays within the 100…120 V AC range and frequency within 47…63 Hz. Confirm that state 0 voltage remains below 20 V and state 1 voltage reaches at least 74 V. For output circuits, check that load current stays within the VA and W ratings for the specific voltage and load type. The 500 V AC channel-to-logic isolation protects the PLC backplane from field transients. Follow Schneider Electric’s installation manual for terminal torque and wire sizing. Do not exceed the [Ith] conventional free air thermal current of 3 A.
Maintenance and Long-Term Reliability
Relay contacts are the primary wear point. Inspect them periodically if the module switches inductive loads frequently. Keep the cabinet humidity within the 5% to 95% non-condensing range. Verify that ambient temperature stays between -25°C and +70°C during operation. The 3 W power consumption and 5.6 W dissipation produce minimal heat, which extends component life. For storage, keep the module between -40°C and +85°C. These practices protect your investment and reduce unplanned downtime.
Compatibility and Integration
The module belongs to the Modicon TSX Micro automation platform. It integrates with TSX Micro PLC racks through the backplane. Inputs accept 2-wire proximity sensors and 100…120 V AC signals. Outputs handle AC and DC loads within the stated limits. The module carries CE, UL, and CSA certifications. Verify that your existing rack and power supply match the TSX Micro platform before ordering.
What to Verify Before You Buy
Confirm your PLC rack accepts TSX Micro I/O bases. Check that your field devices match the 100…120 V AC input range and the relay output ratings. Verify the DIN rail space and terminal block layout in your cabinet. The module weighs 1.00 lbs (0.45 kg) and ships in packaging measuring 2.2 in height, 7.09 in width, and 10.2 in length. Please verify current lifecycle status and availability with SpareTechPLC before ordering.
Frequently Asked Questions
Can the TSXDMZ28AR replace a failed I/O base in an existing TSX Micro rack?
Yes, if your rack accepts TSX Micro I/O bases. The module uses the same DIN rail mount and screw terminal connections. Confirm your rack model and backplane compatibility before ordering.
What input voltage does this module require?
The discrete inputs accept 100…120 V AC at 47…63 Hz. State 1 requires at least 74 V, and state 0 must stay below 20 V. Input current is 11 mA at 50 Hz or 13 mA at 60 Hz.
What types of loads can the relay outputs switch?
Outputs handle 19…264 V AC or 10…34 V DC. Resistive AC loads reach 220 VA at 220 V AC. DC resistive loads reach 40 W at 24 V DC. Inductive loads are rated at 24 VA for 24 V AC-15 and 220 VA for 220 V AC-15.
What is the operating temperature range?
The module operates from -25°C to +70°C and stores from -40°C to +85°C. Humidity tolerance is 5% to 95% non-condensing.
How fast does the module respond?
Output response time is less than 10 ms. Input response ranges from 11…18 ms at state 0 to state 1 at 50 Hz, and up to 24 ms at state 1 to state 0 at 50 Hz.
