How many different ranges can be configured on a 9207? Does each on need a separate task? This will be programmed using CVI.

[mjl]

I am starting a project using a cDAQ and CVI.  I have some devices running on 2.5 Volts, some on 9 Volts.  I am looking to use both current and voltage measurements.  The 9207 supports 16 channels.  Do I need to configure the device with separate tasks for each configuration (+-5,V +-10V, 4-20ma)  or can it be done in one task?

[Cavarval]

Hello,

It has 16 channels. Channels 0 to 7 are voltage inputs and channels 8 to 15 are for current. Unfortunately, each group has a single input range, as shown in the specifications document.

http://www.ni.com/pdf/manuals/375206b_02.pdf#page=5

So, voltage channels are (roughly) +/- 10 V and current channels +/- 20 mA. If you need multiple voltage ranges, you may need different devices.

You need to configure all channels in a single task as explained in the article below. It uses LabVIEW as an example, but the same should be possible in CVI (I'm not much of a CVI person myself, but I think this will help).

Regards,

[mjl]

I realized after the fact that the specs on the 9207 do not support the different voltage ranges.  In addition, the 9207 ADC's accuracy is a lot lower than ones with lower resolution.  I was very surprised to find this out with the assistance of an NI Engineer.  The 9207 can detect small changes in signals, but the actual accuracy of the reading is horrible.  You really need to dig into the spec sheets when selecting these cards.  It is also annoying that the specifications for the different boards are represented in different ways so it is difficult to compare the boards without spending time doing calculations to actually determine noise and error levels.