Driving Relays with PXI-2567

Before driving relays with the PXI-2567, make sure you connect the matching cable and connector to the PXI-2567 as specified in PXI-2567 Pinout and PXI-2567 Topology.
Table 6. PXI-2567 Matching Accessories
Module PXI-2567
Topology Independent
Connector Type D-Sub 78-pin
Front Mounted Terminal Block N/A
Cable N/A
Remote Terminal Block N/A
Custom Connectivity N/A

Driving Single Coil Non-latching Relays

You can use the niSwitch Connect Channels VI or the niSwitch_Connect function to drive relays with the PXI-2567. The following example shows how to connect a relay to channel 7 on the PXI-2567:
  1. Connect the positive terminal of your voltage source to the positive side of the relay coil.
  2. Connect the negative side of the relay coil to pin 44 of the front connector.
    Note Polarized relays do not work if installed incorrectly.
  3. Connect the negative terminal of your voltage source to the common ground return of channel 7 (pin 42).
  4. Call niSwitch_Connect(vi, "ch7", "com7") to close the channel 7 relay. This completes the circuit and drives your relay to channel 7.

    The following figure illustrates how to actuate a relay connected to channel 7.

    Figure 13. Driving Single Coil Non-latching Relay

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    You can also open and close relays by calling the niSwitch Relay Control VI or the niSwitch_RelayControl function. For the relay name, enter K0 for channel 0, K1 for channel 1, and so on.

    Note When scanning the module, a typical scan list entry could be ch2->com2;. This entry drives the relay connected to channel 2.

Driving Two-Coil Latching Relays

The following figure shows an example of using the PXI-2567 to drive a two-coil latching relay.

Figure 14. Driving a Two-Coil Latching Relay

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To close the relay in this example, call niSwitch_Connect(vi, "ch7", "com7"). To open the relay, call niSwitch_Disconnect(vi, "ch7", "com7") and then niSwitch_Connect(vi, "ch6", "com6").

Alternatively, you can actuate the relay by calling the niSwitch Relay Control VI or the niSwitch_RelayControl function. To close the relay in this example, call niSwitch_RelayControl(vi, K7, NISWITCH_VAL_CLOSE_RELAY) to power on the lower coil in the diagram. Then call niSwitch_RelayControl(vi, K7, NISWITCH_VAL_OPEN_RELAY) to power off the lower coil, and call niSwitch_RelayControl(vi, K6, NISWITCH_VAL_CLOSE_RELAY) to power on the other coil and open the relay.