I have three ISM-7400 stepper motors connected to a UMI-7774 interface which is connected to a PXI 7430 controller. All three motors are wired identically with identical switch settings.
Some channels of the UMI-7774 do not respond correctly in my set-up. Here are the motor responses when connected to the UMI-7774 interface unit:
- All three motors operate correctly (forward, reverse, etc.) when independently connected to channel 3 of the UMI-7774. Each motor has its own cabling and the motor/cabling combination is being connected to channel 3.
- For all three motor/cable sets, none will response in any direction on channel 1 of the UMI-7774.
- For all three motor/cable sets, each will respond only in the forward direction when connected to channels 2 and 4 of the UMI-7774.
- With all three motor/cable sets connected to any three channels of the UMI-7774, all channels respond as listed above.
- No red indicator lights of the UMI-7774 were ‘on’ at any time of operation.
NI MAX was used to setup and execute the motor testing above. To insure each channel was setup identically I setup one channel's parameters and applied that setup to all channels. I also visually inspected each channel's setup parameters to insure they were the same.
Channel 1 (no motion) did not have any 'RED' indicators such as limit or home switches engaged. I insured those were disabled (ignored) in NI MAX.
My first guess was a faulty UMI-7774 interface unit. The unit was replaced with a newly purchased unit. The results did not change and were identical to the previous unit (see above results).
The only areas I can imagine the problem could lie is the PXI-7430 Controller/UMI-7774 interface cable, the PXI-7340 controller card itself or an incorrect NI MAX setting (which I believe I have thoroughly checked - but it is possible I missed something).
Does anyone have any suggestions toward identifying the problem?
Respectfully,
-Tim
