PLEASE HELP!!what is the function of this keithley output source VI?

Question

i would like to know what does "trigger delay","sour delay","NPLC","arm count" do in this example.Please help!! thanks!!=D!!
Attachments:
24xx Swp-I Meas-V gpib.llb ‏687 KB

Answer 1

I didn't open your example (I'm not at my work computer), but here is an explanation of the terms:
Trigger delay is the amount of time between a DMM being given a command to take a reading, and the actual reading being taken.  Lets say you want to read the voltage on line A exactly one second after the voltage on line B goes above 2V.  You set the DMM for external trigger with line B connected to the external trigger input on the DMM.  THen set Trigger Delay for 1 second.  Then send the command to read the DMM (Read?).  The DMM will become armed (waiting for trigger).  When line B goes above 2V, the DMM will wait one more second, then read line A.  If you don't want to wait to take a reading, set the trigger to immediate.
Sour stands for source.  I've never heard of source delay.
NPLC is the Number of Power Line Cycles.  In the U.S., we use 60Hz power (50Hz in Europe), so one power line cycle is 1/60 seconds.  When setting NPLC, the DMM will take continuous readings for that length of time, then take an average of all the readings and return this value.  Setting NPLC to 10 will make the DMM take readings ofr 10/60, or 1/6 seconds, and return the average of all readings.  How many readings can be taken during that time interval depends on the DMM, the range setting, and the resolution setting.
Not sure about "arm count", but "arm" means that the DMM has been given a command to read but has not yet received the trigger to take the reading.
Reading a DMM through GPIB involves a series of events:  Arming (GPIB command to read or measure), triggering (immediate or delayed, internal or external), measuring (one measurement or several for averaging), then returning the measurement.
Message Edited by tbob on 05-29-2006 11:54 AM
- tbob
Inventor of the WORM Global