NI PXI-6521 150 V Mechanical Relay Outputs, 30 V Digital Inputs

Starting at $ 605 (view pricing options)
  • 8 nonlatching mechanical relay outputs, 150 VAC/VDC
  • 2 A switching current, 60 W switching power
  • 24 V logic, sinking or sourcing inputs
  • Channel-to-channel isolation: 60 V continuous, 620 Vrms withstand for 5 seconds
  • Prog. power-up states and input filters, watchdog timers, change detection
  • NI measurement services software with configuration utility for easy setup
  • Configure Complete PXI System
  • View Support Resources
The National Instruments PXI-6521 is an industrial digital I/O module with eight 150 VAC/VDC relay outputs with maximum switching power of 60 W, and eight ±30 VDC digital inputs with 60 V channel-to-channel isolation and industry-standard 24 V logic levels. The digital inputs offer connectivity to both sinking and sourcing signals. The NI PXI-6521 is a UL listed device with 60 V continuous and 620 Vrms withstand (5 s) isolation. For added safety the PXI-6521 requires a keyed connector. For added reliability, the module features watchdog timers to recover from a variety of computer and application faults. It also features programmable power-up states, digital filtering, and change detection for optimal control over your application. The PXI-6521 offers a keyed 37-pin D-Sub connector for connectivity to NI low-cost high-voltage accessories. PXI-6521 takes advantage of NI-DAQmx driver software, which helps you achieve shorter setup times and increased productivity.

Specifications Documents

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Specifications Summary


To use the NI PXI-6521 , you need all items in the diagram below. Select Option 1 if you already own a PXI System, or Option 2 if you do not already own a chassis, controller, or software.

Roll over the icons below to learn why you need each item in the system

PXI System

1 Connector Block

1 Cable

NI PXI-6521




NI PXI-6521 and Accessories Only
NI PXI-6521 - 779313-01 Qty $ 605 each
Required Accessories
Connector Block - Screw Terminal
CB-37F-HVD - 779491-01
Qty $ 192 each
Cable - Shielded
SH37F-37M Cable (1m) - 778621-01
Select length:
Qty $ 34 each
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Subtotal: $ 831

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