Velocity and Duty Cycle Measurements Supports NI 9361 Only

Issue Details

• I cannot measure Angular velocity on my multifunctional DAQ board(PCIe-6353) using counter. (Error -200431). Why?

• What's hardware requirements difference for measurements between Angular encoder postion and Angluar velocity? 

Solution

Among NI DAQ devices, only NI 9361 counter module supports measurements of Duty Cycle and Velocity(Angular and Linear). This measurements are usually different with measurement using one counter (ex.Angular Encoder Position. And, multiple counters must be used in a single task. 

A general DIO module can only use one counter in one task. Among NI DAQ devices, only NI 9361 supports Multi Counter.

Additional Information

You can use NI 9361 to perform encoder position and velocity measurements as well as to synchronize the counters with other analog, digital, and counter measurements in your chassis. Below are the unique properties related with the counter.

• The NI 9361 is the only module that has built-in counters itself
• The NI 9361 Counter Input module cannot access the onboard counters from the chassis
• The NI 9361 only supports a single task. 
• The NI 9361 has 8 embeded counters
• If you need to use multiple counters from the NI 9361, you need to add all the required counters to the same task.

Below link is the LabVIEW example page that demonstrates how to continuously acquire velocity measurements using the NI 9361.

• Encoder Velocity Measurements and the NI 9361