how to wait a few seconds after switch action

[小木虫]

Hi,Chad Erickson, thanks for your answers:

  I'd like to know that whether the niDMM property node (time delay property) can be only used in handshaking example? I believe that time delay property can not be used in sychronous scanning example.  

Best regards

小木虫

[chericks1]

Hi 小木虫 ,

The Settle Time property can be used in either example to delay the DMM acquisitions.

Hope this helps!

Chad Erickson

Switch Product Support Engineer
NI - USA

[小木虫]

Hi,Chad Erickson, thanks for your answer:

One question coming: Generally, how long should the relay delay do you think is better when nA or 100pA current is measured using switch? 0.5 second, 1 second or 2 second?

Another question: I'd like to know how can I finish this current measurement: after two relays connect to DMM (c0->r0&c1->r1;), the DMM can measure the current continuously? I can not finish this action using scan list.

Best regards

小木虫

帖子被小木虫在 08-18-2008 05:42 AM

时编辑过了

[木虫]

Hi,Chad Erickson:

I add the niDMM property node (time delay property) in sychronous scanning example, but it seems to does not work.  I set the time interval to 0 or a small number and set the niDMM property/ time delay to1s or more. When I run the program, it finish in short time (50 channles are tested ). Then obviously the time delay does not work in sychronous scanning example.

 Is this right?

Best regards

小木虫

[chericks1]

Hi 小木虫,

I've not had the chance to verify this yet, but the time delay should be imposed before the first measurement.  Try setting a time delay of 10 seconds.  Does the VI take at least 10 seconds to run?

Please let me know!

Chad Erickson
Switch Product Support Engineer

NI - USA

[chericks1]

Hi 小木虫,

One question coming: Generally, how long should the relay delay do you think is better when nA or 100pA current is measured using switch? 0.5 second, 1 second or 2 second?

I'm a proponent of a long delay, as it provides more time for the circuit to transition to a steady state.  However, if you are attempting to achieve top speeds, you might trade a little accuracy for a faster scan rate.

Another question: I'd like to know how can I finish this current measurement: after two relays connect to DMM (c0->r0&c1->r1, the DMM can measure the current continuously? I can not finish this action using scan list.

The above action connects r0 to c0 and r1 to c1 before the DMM takes a measurement.  Please clarify what you mean by "DMM can measure the current continuously".  Are you attempting to have the DMM read at intervals every so often after r0 connects to c0 and r1 connects to c1?

Please let me know!

Chad Erickson

Switch Product Support Engineer

NI - USA