Q-SWITCH 120065-002 Switch Module

Technical Dossier

Product Details And Specifications

Q-SWITCH Series Technical Notes

The Evolution of Q-SWITCH Architecture

The Q-SWITCH series was developed to address the need for modular, field-replaceable switching components in rack-based industrial control systems. Early iterations of the series focused on discrete switching with fixed I/O configurations, operating over standard backplane bus interfaces common to late-generation DCS platforms of the 1990s and early 2000s. As industrial networks transitioned toward Ethernet-based fieldbus protocols (PROFINET, EtherNet/IP, Modbus TCP), later Q-SWITCH revisions incorporated enhanced isolation circuitry and improved EMI shielding to maintain signal integrity in electrically noisy plant environments.

The 120065-002 variant represents a mid-generation design with backward compatibility to earlier rack chassis, making it a critical spare for facilities that have not yet completed full system migration. Compatibility considerations include backplane voltage rail specifications (typically 5 VDC and 24 VDC), connector pinout standards, and firmware revision alignment with the host controller. Facilities operating mixed-generation Q-SWITCH hardware must verify revision compatibility before substitution.

Q-SWITCH Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly stocked components within the Q-SWITCH series. Each entry is classified by functional category.

Switch & Control Modules

• 120065-002: Standard switch module; discrete switching, backplane-mounted, DCS rack compatible
• 120065-001: Base-revision switch module; predecessor to -002, identical form factor, earlier firmware baseline
• 120065-003: Enhanced switch module; extended temperature range (-40°C to +70°C), improved isolation
• 120065-004: High-density switch module; dual-channel switching, increased contact rating
• 120065-005: Relay output switch module; dry contact outputs, 250 VAC rated

Digital Input (DI) Modules

• 120066-001: 16-channel 24 VDC digital input module; sink/source configurable
• 120066-002: 32-channel 24 VDC digital input module; high-density rack format
• 120066-003: 8-channel 120 VAC digital input module; field-level voltage compatible

Digital Output (DO) Modules

• 120067-001: 16-channel 24 VDC digital output module; transistor sourcing type
• 120067-002: 16-channel relay output module; Form C contacts, 2A per channel
• 120067-003: 8-channel high-current output module; 5A per channel, fused

Analog Input (AI) Modules

• 120068-001: 8-channel analog input module; 4–20 mA / 0–10 V selectable
• 120068-002: 16-channel analog input module; 16-bit resolution, HART pass-through

Power Supply Modules

• 120070-001: Rack power supply module; 24 VDC output, 10A, redundancy-capable
• 120070-002: Redundant power supply module; hot-swap, load-sharing architecture

Communication & CPU Modules

• 120071-001: CPU/controller module; primary processor for Q-SWITCH rack, Modbus RTU/TCP
• 120072-001: Ethernet communication adapter; 10/100 Mbps, RJ45, DIN-rail or rack mount
• 120072-002: PROFIBUS DP communication module; slave mode, up to 12 Mbps

Sourcing Hard-to-Find & Obsolete Q-SWITCH Parts

Several Q-SWITCH series modules, including early revisions of the 120065 switch module family, have reached end-of-manufacture (EOM) status. Original equipment manufacturers (OEMs) typically discontinue active production support 10–15 years after a platform's commercial release, leaving facilities dependent on secondary market sourcing for lifecycle extension.

Quality Control for the Q-SWITCH Range

Q-SWITCH modules, particularly backplane-mounted switch and I/O modules, require functional validation beyond visual inspection due to the complexity of their internal bus communication and isolation circuitry. DriveKNMS applies the following test protocol to all Q-SWITCH series units processed through our facility:

• Backplane Bus Integrity Test: Each module is seated in a reference rack chassis and subjected to full backplane communication cycling to verify address recognition, data throughput, and error-free bus arbitration.
• Switching Function Verification: For switch modules (120065-xxx series), all switching channels are exercised through full open/close cycles under rated load conditions. Contact resistance is measured and compared against OEM specifications.
• Isolation Resistance Test: Channel-to-channel and channel-to-chassis isolation is measured at 500 VDC using a calibrated megohmmeter. Minimum acceptable isolation: 100 MΩ.
• Thermal Cycling: Units are subjected to accelerated thermal cycling (0°C to 55°C, 5 cycles) to identify latent solder joint or component failures not detectable at ambient temperature.
• Firmware Revision Audit: Where applicable, embedded firmware version is read and documented. Customers are notified of any revision mismatch relative to their host system baseline.
• Final Burn-In: All units undergo a minimum 48-hour powered burn-in under simulated operational load prior to shipment.