Model Explanation

PXI: PXI bus platform (modular instrument standard)

2533: Product serial number, representing a 256 cross-point solid-state matrix switch

Alias: NI-2533, PXI-2533 (SSR matrix)

Function Positioning: 4×64 single-line high-density matrix, without mechanical contacts, suitable for high-reliability, long-life signal routing

Technical Parameters

Cross-point Number: 256 (fixed 4 rows × 64 columns single-line matrix) NI

Relay Type: Solid-state relay (SSR), without mechanical lifespan limit NI

Maximum Switching Voltage: ±55 VDC / 30 VACrms

Maximum Switching Current: 1 A / channel

Maximum Switching Power: 55 W (all channels closed simultaneously) NI

Bandwidth (‑3 dB, 50 Ω): Typical > 1.5 MHz

Thermal Emissivity: Typical 2 μV

Channel Isolation Resistance: Typical > 2 GΩ (DC)

Path Resistance: Typical 1 Ω (row to column)

Switching Time: Typical 724 μs, maximum 2.5 ms

Scanning Rate: 400 cross-points / second (≤ 20 V, 1 A) NI

Simultaneous Drive Limit: 256 relays (fully closed)

Trigger Characteristics: PXI trigger line 0–7, minimum pulse width 70 ns; output trigger 1–62 μs software selectable

I/O Connector: 68-pin male SCSI type NI

Size: 3U PXI single slot (216 × 20 × 130 mm) NI

Weight: Approximately 238 g NI

Operating Temperature: 0–55 °C NI

Interface and Communication Configuration

PXI Bus Interface: Standard 3U PXI backplane connector, providing power supply, trigger, clock and communication

Front-end I/O Connector: 68-pin male SCSI, high-density signal output NI

Terminal Block (optional): TB-2625, etc., supports screw terminals or ribbon cable connections

Control Communication: PXI bus, compatible with NI- SWITCH, MAX, LabVIEW, TestStand

Trigger Synchronization: Hardware trigger input/output, nanosecond-level synchronization, improves test throughput

Expansion Capability: Multi-module cascading, can be extended to larger matrix size Core function

Fixed 4×64 high-density matrix: 256 intersections, single-line topology, meeting the requirements of multi-channel signal routing for NI.

Infinite mechanical lifespan: Solid-state relays have no contact wear, suitable for long-term continuous operation and high-frequency switching scenarios for NI.

Low thermoelectric potential and high isolation: Typical 2 μV thermal offset, >2 GΩ isolation, suitable for low-level, high-precision measurements.

High power switching capability: Single channel 1 A, total power of 55 W, capable of simultaneously driving all channels to close for NI.

Hardware triggering and deterministic timing: Minimum trigger pulse width of 70 ns, precise synchronization of multiple instruments, improving test efficiency.

On-board relay count: Real-time monitoring of switching times, predicting maintenance cycles, reducing unexpected downtime. Applicable scenarios

Semiconductor testing: Wafer testing, parameter testing, aging screening, requiring long-term high-reliability switching.

Automotive electronics: ECU verification, sensor/lux signal simulation, wiring harness conduction test, high-frequency switching.

Aerospace: Multi-channel signal routing, fault injection, aviation bus testing, long-life requirement.

Industrial automation: Process control, signal conditioning, data acquisition system, continuous operation scenario.

Precision testing and measurement: Low-level signal switching, instrument calibration, sensor signal acquisition, low thermal offset requirement.

Usage and Maintenance Instructions

Usage Points

Installation: Standard 3U PXI chassis single slot, lock the panel, ensure the backplane connector is reliably connected.

Configuration: Set channel mapping, trigger parameters and scan sequence through NI-SWITCH or MAX software.

Cabling: Connect TB-2625 terminal block with 68-pin SCSI, then transfer to the tested device; strictly follow voltage/current/power limits to avoid overload.

Operation Monitoring: Use the onboard relay counting function to regularly read the switching times and evaluate the module status.

Environment: Operating temperature 0–55 °C, avoid strong electromagnetic interference, dust and condensation.

Maintenance Instructions

Regular Inspection: Check the connector tightness and whether the terminal block wiring is loose every quarter, and clean the surface dust.

Life Management: Solid-state relays have no mechanical lifespan, but electrical stress needs to be monitored to avoid long-term over-power operation.

Fault Troubleshooting: When the channel is not connected or has poor contact, first check the wiring and terminal block, then diagnose the relay status through software; when the signal is abnormal, check the grounding and shielding.

Storage: When not in use for a long time, disconnect the power supply and store in a dry, dust-proof environment to avoid connector moisture and oxidation.