Schneider Electric TSX37 Modules

Technical Dossier

Product Details And Specifications

Schneider Electric TSX37 Series: Comprehensive Module Range and Technical Overview

The Schneider Electric TSX37 series, part of the Modicon TSX Micro programmable logic controller family, holds a significant installed base across global heavy industries including petrochemical plants, nuclear facilities, oil refineries, water treatment stations, and continuous manufacturing lines. Introduced as a compact yet capable mid-range PLC platform, the TSX37 series became a standard automation backbone throughout the 1990s and 2000s in European and Asian industrial markets. Its modular rack architecture, deterministic scan cycle, and broad I/O expansion capability made it a preferred choice for process engineers requiring reliable discrete and analog control without the overhead of full-scale DCS infrastructure. Today, the TSX37 series is in its mature/end-of-life phase; Schneider Electric has transitioned customers toward the Modicon M340 and M580 platforms. However, tens of thousands of TSX37-based systems remain operational globally, creating sustained demand for original spare parts, tested replacement modules, and lifecycle extension support.

The Evolution of TSX37 Architecture

The TSX37 series was launched as the successor to the TSX17 compact PLC line, offering expanded memory, faster processing, and a modular bus structure compatible with the FIPIO and Uni-Telway fieldbus protocols. Early variants such as the TSX3705 and TSX3708 provided base configurations with onboard I/O and limited expansion slots. The mid-generation TSX3710 and TSX3720 models introduced enhanced CPU performance, expanded program memory (up to 16K instructions), and support for additional analog and specialty modules via the TSX BUS expansion rack. Late-generation variants added Ethernet connectivity options through communication adapters, bridging the TSX37 into modern SCADA and MES environments. Compatibility challenges arise primarily when integrating TSX37 racks with newer Modicon platforms: the proprietary Uni-Telway serial protocol is not natively supported by M340/M580 CPUs without gateway modules, and TSX37 I/O modules are not hot-swappable in the same manner as later Modicon X80 I/O. Engineers maintaining mixed-generation plants must account for these protocol and physical bus differences when planning partial migrations or expansions.

TSX37 Full Catalog & Functionalities (SKU List)

The following SKUs represent the core and most commonly sourced modules within the TSX37 series, organized by functional category. All models listed are verified members of the TSX Micro TSX37 product family.

CPU / Base Controllers

• TSX3705028DR1: Compact base unit, 28 I/O, relay output, 6K instructions
• TSX3708028DR1: Base unit, 28 I/O, relay, 8K instructions, onboard display
• TSX3710001: TSX37-10 CPU module, 16K instructions, PCMCIA slot, Uni-Telway port
• TSX3710028DR1: TSX37-10 base, 28 I/O, relay output, integrated CPU
• TSX3710028DT1: TSX37-10 base, 28 I/O, transistor output, 24VDC
• TSX3720028DR1: TSX37-20 base, 28 I/O, relay, extended memory, dual port
• TSX3720028DT1: TSX37-20 base, 28 I/O, transistor, 24VDC, high-speed counter
• TSX3722028DR1: TSX37-22 base, 28 I/O, relay, FIPIO master port integrated

Digital Input Modules (DI)

• TSX DEZ 12D2: 12-channel 24VDC digital input expansion module
• TSX DEZ 32D2: 32-channel 24VDC digital input, high-density rack module
• TSX DEZ 08D5: 8-channel 48VDC digital input, industrial isolation

Digital Output Modules (DO)

• TSX DSZ 08R5: 8-channel relay output module, 250VAC/2A per channel
• TSX DSZ 32T2: 32-channel transistor output, 24VDC, 0.5A per channel

Analog Input/Output Modules (AI/AO)

• TSX AEZ 414: 4-channel analog input, 4–20mA / 0–10V, 12-bit resolution
• TSX ASZ 401: 4-channel analog output, 4–20mA, 11-bit resolution
• TSX AEZ 802: 8-channel analog input, thermocouple/RTD, temperature module

Communication & Specialty Modules

• TSX SCP 114: PCMCIA serial link card, RS-485 / Uni-Telway / Modbus RTU
• TSX ETZ 410: Ethernet TCP/IP communication module, 10BASE-T, Modbus TCP
• TSX CAY 21: 2-axis motion control module, stepper/servo interface

Sourcing Hard-to-Find & Obsolete TSX37 Parts

Schneider Electric officially discontinued active production of the TSX37 series, with end-of-commercialization notices issued progressively from 2010 onward. Standard distribution channels no longer stock the majority of TSX37 modules as new inventory. DriveKNMS specializes in lifecycle extension support for the TSX37 platform, maintaining a dedicated inventory of tested original modules sourced through authorized surplus channels, factory returns, and decommissioned plant buybacks. For operators of long-cycle assets — nuclear, petrochemical, and utility infrastructure — where a full PLC migration is not operationally or financially viable within the current maintenance window, DriveKNMS provides a documented alternative to forced platform upgrades. All sourced TSX37 units are individually serialized, tested against original Schneider Electric functional specifications, and supplied with full traceability documentation. Emergency same-day quotation is available for critical plant breakdown scenarios.

Quality Control for the TSX37 Range

The TSX37 series presents specific quality verification challenges due to its proprietary backplane bus architecture and the age profile of available inventory. DriveKNMS applies a dedicated test protocol for all TSX37 modules prior to shipment. CPU modules including the TSX3710001 are powered up and subjected to full program load/execute cycles using reference ladder logic routines, with Uni-Telway communication verified against a reference master station. I/O modules are tested channel-by-channel using calibrated signal sources and loads, with leakage current and isolation resistance measured to confirm that aging components remain within specification. Analog modules are calibrated against NIST-traceable references to verify linearity and offset. Backplane connectors are inspected under magnification for pin deformation, oxidation, and mechanical wear — a common failure mode in modules that have experienced repeated insertion cycles. All modules that pass the full test sequence are issued a DriveKNMS test certificate with date, technician ID, and measured parameters.