PXI-2503 Relay Replacement

The module uses electromechanical armature relays.

Replacement Relay Part Number
NEC-TOKIN EF2-4.5NUX-L6
M3 Distribution (10 relays) 197488A-01

Complete the following steps to replace a failed relay.

Locate the 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 hardware diagram in PXI-2503 Overview and the following figure and table for relay locations.

    Relay NameReference Designator
    CH0K32
    CH1K1
    CH2K2
    CH3K3
    CH4K4
    CH5K5
    CH6K6
    CH7K7
    CH8K8
    CH9K9
    CH10K10
    CH11K11
    CH12K12
    k13K12
    CH13K13
    CH14K14
    CH15K15
    CH16K16
    CH17K17
    CH18K18
    CH19K19
    CH20K20
    CH21K21
    CH22K22
    CH23K23
    BC01K24
    BC23K25
    BC02K26
    CJTEMPK27
    1WIREK28
    HLSELK29
    AB0K30
    AB2K31
  3. Locate the assembly and serial number labels on the board with the relay you want to replace. White labels indicate the board was assembled using lead solder (Sn 63 Pb 37). Green labels indicate the board was assembled using lead-free solder (Sn 96.5 Ag 3.0 Cu 0.5). Lead-free assemblies have assembly numbers ending in L.

Replace the Relay

Note NI recommends using lead-free solder for relay replacement on lead-free assemblies, and lead solder for relay replacement on lead assemblies.
Note Do not rework lead assemblies using a lead-free work station. Lead solder from the unit could contaminate the station.
Note If a lead-free assembly is reworked with lead solder, label the assembly to indicate this condition. This rework can prevent the same unit from being reworked later on a lead-free solder station, because it could contaminate the station.

Make sure that you have the following items:

  • Temperature-regulated soldering iron set to 316 °C (600 °F) for lead solder rework or 371 °C (700 °F) for lead-free solder rework
  • 63/37 Tin/Lead solder (flux core) for lead solder rework
  • 96.5/3.0/0.5 Tin/Silver/Copper solder (flux core) for lead-free solder rework
  • Solder wick
  • Fine pick
  • Isopropyl alcohol
  • Cotton swabs

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

Note You can use the Switch Soft Front Panel to reset the relay count after you have replaced a failed relay.