USER GUIDE
NI 6520/6521
This document describes how to use the National Instruments 6520 and
6521 data acquisition (DAQ) devices with NI-DAQ 7.5 or later. Device
specifications can be found on
ni.com/manuals
. If you have not already
installed the DAQ device, refer to the
DAQ Getting Started Guide
for
installation instructions.
The NI 6520/6521 contains five Form A single-pole single-throw (SPST)
non-latching relay outputs, three Form C single-pole double-throw (SPDT)
non-latching relay outputs, and eight channel-to-channel isolated industrial
inputs. The relay’s maximum switching power is 60 W/60 VA. The
maximum switching voltage for the NI 6520 is 30 Vrms/42.4 V
pk
/
60 VDC. The maximum switching voltage for the NI 6521 is
150 VDC/VAC.
The NI 6520/6521 uses positive logic. A digital high energizes the relay,
and a digital low deenergizes it. In the energized state, the common (COM)
contact is connected to the normally open (NO) contact. For Form C relays
in the deenergized state, the common contact is connected to the normally
closed (NC) contact. For Form A relays in the deenergized state, the
common contact is not connected to the normally open (NO) contact. When
the board (PC) is powered off, the relays are deenergized.
Caution
(NI 6521 Only)
This 150 V Measurement Category II module features 1,400 Vrms
isolation between I/O channels and the backplane, as verified by a dielectric withstand test,
5 s maximum. For more information on hazardous voltage requirements and safety
information for the NI 6521, refer to the
Contents
Configuration .......................................................................................... 2
Functional Overview............................................................................... 3
Safety Information .................................................................................. 4
Related Documentation........................................................................... 6
Features ................................................................................................... 6
Digital Filtering................................................................................ 6