Switch Hardware and Software

[David Ng]

Hi All

I experienced a problem to connect channel ab0 and ab2 to the respective measurement channel so that I can get a resistance reading. I'm using SCXI-1127 with 1331 and a DMM of HP34401A.

I have done my wiring correctly and now it's a matter of coding it correctly. There are lots of way to do this in my mind. Tried each one of them and didn't work.

Any help (software or detail of coding sequence) will be very much appreciated.

David Ng

[Guy Ferraro]

What is controlling the SCXI-Chassis?
What version of NI-SWITCH do you have?

[David Ng]

I have Labview 7.1 which means I'll have the most updated Ni-switch. A 421 PCI card is controlling my chassis either through traditional Ni-DAQ or Ni-DAQmx.

My computer has the following:
1. 488.2 GPIB controller
2. PXI - not related for this particular problem
3. NI 421 PCI card
4. SCXI - 1000 chassis
5. SCXI - 1127 Mechanical relay switch that will need to be set up in 16x1 4-wire mux
6. SCXI - 1331 module

Thanks for following up so fast

Dave

[Guy Ferraro]

- Use the chassis created in DAQmx.
- In MAX (SCXI-1127 property) select the SCXI-1331 as the terminal block for the SCXI-1127.
- Use the shiping NI-SWITCH example found in: F:\Program Files\National Instruments\LabVIEW 7.1\examples\instr\niSwitch called niSwitch Making Connection on a Switch.vi.
- Delete the second connect vi and wait for debounce
- Point to your SCXI-1127 (SC1Mod4 for example)
- Change the topology to "1127/4-Wire 16x1 Mux"
- Check the NI-SWITCH help file (Start>>Programs>>National Instruments>>NI-SWITCH>>Documentation>>NI Switches help) for valid channel names under: NI Switch Help>>Devices>>SCXI-1127/1128>>4-wire 16x1 Topology

[Guy Ferraro]

Correction: your NI-SWITCH examples should be in the root directory.
\Program Files\National Instruments\LabVIEW 7.1\examples\instr\niSwitch

[David Ng]

thanks

Your suggestion really helps a lot!

Dave