Data Acquisition Idea Exchange

I would like to see a C series module just like the NI 9474 only with push-pull outputs.

Dear NI Idea Exchange,

I had a service request recently where the customer wished to use a mass flow meter, using the HART protocol (massive industrial protocol used worldwide with over 30 million devices) to communicate updated values to a cRIO 9074 chassis using a NI 9208 module.

They did not know how they could use this protocol with our products. There was only one example online regarding use of this protocol using low level VISA functions. There is currently no real support for this protocol.

I suggested that if they wished to use this sensor they would be required to convert it to a protocol we do support, for example Modbus or to RS-232 (using a gateway/converter).

Then they could use low level VISA functions to allow the data communication.

They were fine with doing this but they felt that NI should probably support this protocol with an off-the-shelf adaptor or module. This is the main point of this idea exchange.

There is clearly a reason why we do not currently provide support for this protocol in comparison to PROFIBUS or Modbus.

I thought I would pass on this customer feedback as it seemed relevant to NI and our vision. 

Regards,

Dominic Clarke

Applications Engineer

National Instruments UK

I am not an electircal engineer, so I have no idea if there is some reason this has not been implemented in exiting versions of teh cDAQ chassis.  But there are a whole host of applications where a user wants to do Hardware timed digital output to different channels using DIFFERENT time bases.  It would be nice to have more than one DO timing engine available.  I would love to see that in future versions of the cDAQ chassis.

Thanks

Matt

In the case of a power failure on a cRIO or cDAQ having a C Series module which could provide back up power would be helpful.

We can use this to:

• Keep the system clock going on cRIOs that do not have an internal battery
• Take time stamp of the crash
• Grab the last known value of shared variables and store them for the reset
• Perform any shutdown operations that are nessecary

I'm not sure who reads this, but I'm not seeing any feedback in the forum so I thought I'd post up here.   This may seem like a simple thing, but hopefully my pain will be someone else gain.  I messed with this off and on for two months before I finally figured it out.  It's probably obvious to those who work with this equipment every day and have EE degrees, but not so much to those of us who do not. 

Please see http://forums.ni.com/t5/Multifunction-DAQ/Measuring-220VAC-with-CompactDAQ/td-p/1145956 for a description of the issues I was having. 

Some will tell me to "search"... well, I did.  ...and everywhere I looked all I found was that I needed to measure from the power leg to ground.  All of the examples either were only measuring 120 which is fine since what you have is one power leg and neutral... which is basically ground!  So those numbers come out fine.  Or they were for 3 phase, which I don't use currently.  BUT when you try and measure anything with two power legs (basically anything between 208VAC to 240 VAC) the numbers don't work out right if you try to measure between each power leg to ground and then try to recombine them and plug them into the Power VI's.  Not one place that I looked did it tell me that I need to measure both power legs across a single channel.  I only finally tried it because I'd done pretty much everything else.  I know this is pretty basic stuff, but when all you give me says one thing... that's what we do.  Just trying to help others.

Thanks,

Chad