PXI-2570 Overview

PXI-2570 Pinout



Table 1. Signal Descriptions
Signal Description
COMx Routing destination for corresponding signal connections
NCx Normally closed signal connection
NOx Normally open signal connection

PXI-2570 Hardware Diagram

This figure shows the hardware diagram of the module.



PXI-2570 Topology

Module software name: 2570/40-SPDT (NISWITCH_TOPOLOGY_2570_40_SPDT)

The module is composed of 40 armature latching SPDT relays.

For certain applications, you may need to increase the default settling time.

Note Switching inductive loads (for example, motors and solenoids) can produce high voltage transients in excess of the module's rated voltage. Without additional protection, these transients can interfere with module operation and impact relay life.

40-SPDT Topology



Making a Connection

You can control the channels using the niSwitch Connect Channels VI or the niSwitch_Connect function.

To connect the NO terminal to the COM terminal of that channel, disconnect the NC terminal from the COM of that channel.

For example, to connect NO2 to COM2, use the following code:

niSwitch_Disconnect(vi, "NC2", "COM2")
niSwitch_Connect(vi, "NO2", "COM2")
Note To connect NO to COM you do not need to disconnect NC from COM after the module has been reset or a call to the niSwitch Disconnect All Channels VI or the niSwitch_DisconnectAll function has been made.
Note niSwitch_Disconnect(vi, "NC2", "COM2") does not activate the relay until niSwitch_Connect(vi, "NO2", "COM2") is executed.

PXI-2570 Relay Replacement

The module uses electromechanical armature relays.

Ensure you have the following:

  • Temperature-regulated soldering iron
    • Set to 371 °C (700 °F) for lead-free solder rework
    • Set to 316 °C (600 °F) for lead solder rework
  • Solder
    • 96.5/3.0/0.5 Tin/Silver/Copper solder (flux core) for lead-free solder rework
    • 63/37 Tin/Lead solder (flux core) for lead solder rework
  • Solder wick
  • Fine pick
  • Isopropyl alcohol
  • Cotton swabs
Note NI recommends using lead-free solder for relay replacement on lead-free assemblies, and lead solder for relay replacement on lead assemblies.
Notice Do not rework lead assemblies using a lead-free work station. Lead solder from the unit could contaminate the station.
Notice If a lead-free assembly is reworked with lead solder, label the assembly to indicate this. This can prevent the same unit from being reworked later on a lead-free solder station, which could contaminate the station.

Complete the following sets of steps to disassemble your module and replace a failed relay.

  1. Ground yourself using a grounding strap or a ground connected to your PXI chassis.
    Note Properly grounding yourself prevents damage to your module from electrostatic discharge.
  2. Locate the relay you want to replace. Refer to the following figure and table for relay locations.


    Channel NameRelay NameChannel NameRelay Name
    CH0 K0CH20K20
    CH1K1CH21K21
    CH2K2CH22K22
    CH3K3CH23K23
    CH4K4CH24K24
    CH5K5CH25K25
    CH6K6CH26K26
    CH7K7CH27K27
    CH8K8CH28K28
    CH9K9CH29K29
    CH10K10CH30K30
    CH11K11CH31K31
    CH12K12CH32K32
    CH13K13CH33K33
    CH14K14CH34K34
    CH15K15CH35K35
    CH16K16CH36K36
    CH17K17CH37K37
    CH18K18CH38K38
    CH19K19CH39K39
    Note Older versions of this module might have adhesive plastic lead covers that you must remove. The module retains full specifications even if these covers are not reinstalled.
  3. Locate the assembly and serial number labels on the board with the relay you want to replace.
    • Green labels indicate the board was assembled using lead-free solder (Sn 96.5Ag 3.0Cu 0.5). Lead-free assemblies have assembly numbers ending in L.
    • White labels indicate the board was assembled using lead solder (Sn 63Pb 37).
    The different label types are shown in the following figure.

Tip Use the NI-SWITCH Switch Soft Front Panel to reset the relay count after you have replaced a failed relay. Refer to the Switch Soft Front Panel Help for more information.

Refer to the following topics for relay instructison for through-hole and surface-mount relays depending on the revision of your module assembly:

Through-Hole Relay Replacement

Refer to the following table for information about ordering replacement relays.

Replacement Relay Part Number
AXICOM (Tyco Electronics) (relay manufacturer) IM42PNS (7-1462039-8)
NI relay kit (10 relays) 781678-01

Replace the relay as you would any other through-hole part.

Surface-Mount Relay Replacement

Refer to the following table for information about ordering replacement relays.

Replacement Relay Part Number
AXICOM (Tyco Electronics) (relay manufacturer) IM42GR (3-1462037-1)
NI relay kit (10 relays) 779356-01

If you have a surface mount rework station, replace the relay as you would any other surface mount part. Otherwise, complete the following steps to replace the relay:

  1. Use the soldering iron and solder wick to remove as much solder from the relay pads as possible. Do not leave the soldering iron on any lead for more than 5 seconds.
    Note If it is necessary to reapply the soldering iron to the pad, allow the connection to cool completely before reapplying the soldering iron.
  2. Apply heat to the pads one at a time, and use the pick to gently pry the relay pins from the pads. Make sure that the solder is molten before prying.
    Notice Using excessive force on a soldered pad can result in lifting the PCB trace and ruining the board.
  3. Remove the relay.
  4. Clean the pads with isopropyl alcohol and cotton swabs.
  5. Place the new relay on the PCB pads and solder.
  6. Remove the excess flux with isopropyl alcohol and cotton swabs.
    Notice Do not use flux remover to clean the board after relay replacement.