Page 1 of 1

Using 7705 with 201 DMM

Posted: July 17th, 2011, 8:20 pm
by RapidKris
I am using Keithley 2701 DMM with 7705 control module in my application. I need to use four channels of 7705 as normal switches that has to open/close (each independently) with respect to time. I also need to configure other 20 channels of it as measurement channels on which DC voltage, AC voltage, AC current, DC Current and temperature are to be measured. I designed two algorithms. Can any one help me in choosing which one is good.
Option A:

1. open/close the 4 channels that are using as switches (multiple channels at a time)
2. close all the channels that are to be measured (multiple channels at a time)
3. read data

Iterate the above three steps in a loop and update/modify the channels that are to be closed / opened.
Option B:

1. open/close the 4 channels that are using as switches (multiple channels at a time)
2. close single channels at a time that are to be measured (multiple channels at a time) and read data for that channel
3. repeat step 2 for all channels that are to be measured

Iterate the above three steps in a loop and update/modify the channels that are to be closed / opened. Timing is very critical in my application.

Is there any better algorithm, I have very little knowledge on this and any minor information will be helpful to me.

Re: Using 7705 with 201 DMM

Posted: July 26th, 2011, 7:38 am
by Dale C
My suggestion would Option B.
This way the measurement would be sequential and not interfere with the other closed channels.