II. Model Interpretation

PXI: PCI eXtensions for Instrumentation, compatible with PXI/PXIe hybrid slots.

2523: 2500 series (general-purpose relay switch), 23 represents 26 channels, DPDT double-pole double-throw, 100V/2A specification.

Part Number: 778572-23.

Status: In stock (NI mainstream DPDT general switch module).

III. Technical Parameters

Channel Configuration

Relay Type: 26 independent DPDT (Form C, double-pole double-throw) non-retentive armature relay.

Topology: 26 fully independent double-pole channels, each channel includes COM+/COM− (common terminal), NO+/NO− (normally open), NC+/NC− (normally closed).

Electrical Characteristics

Maximum switching voltage: 100 VDC (channel-to-channel / channel-to-ground, CAT I).

Maximum switching current: 2 A (per channel, switching / carrying).

Maximum switching power: 60 W, 62.5 VA (DC–60 Hz, per channel).

On-resistance: <0.5 Ω (typical).

Thermal offset: Low (suitable for precise differential measurement).

Relay Life: 10^8 times (mechanical life, typical).

Contact Material: Palladium-ruthenium alloy plated gold (low contact resistance, corrosion-resistant).

Dynamic Performance

Bandwidth: 36 MHz.

Switching Time: <1 ms (typical).

Scan Rate: 145 cycles/second.

Physical and Environmental

Size: 3U PXI (100 mm×160 mm), single slot.

Weight: Approximately 0.35 kg.

Operating Temperature: 0–55 °C; Storage: −40–70 °C.

Humidity: 10%–90% RH (no condensation).

Power Consumption: 5 W (5 V).

IV. Interface and Communication Configuration

Host Interface: PXI hybrid bus (compatible with PXIe/PXI), supports hot plugging, plug-and-play.

Signal Interface: 160-pin DIN 41612 female connector (front panel), each channel leads out COM+/COM−, NO+/NO−, NC+/NC−, suitable for differential / floating ground wiring.

Trigger and Synchronization: PXI trigger line (0–7, minimum pulse width of 150 ns), supports multi-module synchronous scanning and timing control.

Driver Software: Compatible with NI-SWITCH, LabVIEW, TestStand, C/C++/Python API, supports IVI standard driver.

V. Core Functions

26 independent DPDT double-pole double-throw switching: Each channel can achieve differential dual-line common terminal and NO/NC dual-select, suitable for differential signals, floating ground load, avoiding common ground interference from NI.

Medium-power differential switching: 100 V/2 A double-pole synchronous switching, covering low-voltage differential power supply, sensors, actuators (heaters, fans, solenoid valves) control requirements.

Low-resistance low-noise precise switching: <0.5 Ω on-resistance + low thermal offset, suitable for precise differential voltage / current signal routing and measurement.

Built-in relay count: Built-in action count, supports predictive maintenance, early replacement of aged relays.

Software programmable and scanning: Supports immediate control and list scanning, suitable for automated test sequences and real-time control.

VI. Application Scenarios

Automation Testing (ATE): Differential power / signal routing of circuit boards, modules, systems, functional testing and aging testing.

Differential / Grounded Signal Switching: Dual-line signal switching of sensors, instruments, communication equipment, eliminating common ground interference. Power and Load Control: Low-voltage differential power distribution, relay/contactor drive, heater/fan/valve control.

Industrial Control and Monitoring: Equipment status monitoring, alarm circuit control, small actuator drive.

Automotive Electronic Testing: Differential power / I/O interface testing for on-board ECU, sensors, actuators.

VII. Installation and Maintenance Instructions

Installation and Wiring

Module: Unplug and power off, insert into PXI/PXIe mixed slot, tighten the fixing screws.

Wiring: Connect COM/NO/NC differential loads / tested equipment according to channel definitions. Do not exceed 100 V, 2 A.

Grounding: Secure the chassis to the system ground to reduce electromagnetic interference.

Software Configuration

Install NI-SWITCH driver, NI-MAX recognizes the module, configure DPDT channel topology.

Programming: Call the switch VI in LabVIEW, or configure the test sequence in TestStand to achieve channel control and scanning.

Daily Maintenance

Cleaning: Wipe the panel with a soft cloth after power off, avoid liquid entering the DIN interface.

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

Protection Mechanism: Avoid overvoltage (>100 V), overcurrent (>2 A), inductive loads (without surge suppression), extend relay lifespan.

Static Protection: Wear an anti-static wristband when plugging and unplugging the module, ensure good grounding of the chassis.