ADLINK PXI-7921 - Manual (Page 7)

Introduction • 1
1
Introduction
ADLINK PXI-7921 is a relay multiplexer module which consists of 24 2-wire
relays (DPDT, 2 Form C). PXI-7921 provides 48x1 1-wire and 24x1 2-wire and
12x1 4-wire configurations and typically connects one instrument, such as a
DMM, a digitizer or a signal source, with many points which need measurement
or excitation.
Relays of PXI-7921 can be updated by either direct-update mode or auto-scan
mode. The latter mode supports scanlist of 1k-sample for deterministic
scanning.
PXI trigger functions are fully supported and software programmable. The
multiple switch modules can be synchronized and triggered without additional
field wiring.
For safety critical applications, PXI-7921 module can switch to the preset state
by either asserting emergency shutdown manually, or watchdog timer overflow
event.
1.1 Features
• PXI specifications Rev. 2.0 compliant
• 3U Eurocard form factor, CompactPCI compliant (PICMG 2.0 R3.0)
• PICMG 2.1 R2.0 CompactPCI Hot-Swap specifications compliant
• 24-CH DPDT (2 Form C) non-latching relays
• Contact rating
• 2A switching, 2A carrying
• 220V
DC
, 125V
AC
• 125 operations per second
• 1k-sample scanlist for deterministic scanning
• Provides handshaking signals to trigger external instruments
• Programmable emergency shutdown function and Watchdog timer for
safety critical applications
• Three auxiliary 3.3V/TTL digital inputs/outputs with 5V tolerance
• Supports PXI backplane triggers to synchronize multiple modules
• Fully software programmable