Cannot use built in CJC in Scb68 due to error 200077 while config task in daqmx

[rupak]

I am trying to read temperature of a type T, TC.When i used constant source CJC i was able to read quite fine. I now want to read using In built CJC(which is in the SCB 68 i was using).I am having difficulty in going about it.When i configure in daqmx task it shows that task could not be saved because of error 200077.Any suggestions!

[RobCole]

Error -200077 for DAQmx means that the system does not think that this is a valid option for the device.

Ensure that in MAX, the device has an SCB-68 listed as its accessory. Click on the device, click the properties button and then look on the Accessories tab page. There should be a drop-down there to select the accessory for this device.

Also, ensure that the switches on the SCB-68 have the Temp Sensor enabled. There should be a quick reference label inside the lid of the SCB-68 box.

I hope this helps.

     Rob

[rupak]

Dear Rob

Thanks for your interest in this matter.

However I had already enlisted scb68 as an accessory  and also ticked in the box "temperature sensor enabled" in configuring SCB 68 with MAX.Also I had made the switch settings for "differential - temperature sensor enabled" as mentioned in the "scb 68 quick reference label".

In spite of it I got the error 200077 when trying to use in built option for cjc .

Also it would be a great help if you could tell me how to use the "channel" option for cjc.In fact I tried it in the following way but it did not work.I first put the thermocouple input to ai1 & ai9 in differential mode, and then tried to configure a channel for cjc.So in daqmx task i chose :analog input-temperature-thermocouple-etc and then for cjc  option i selected channel.However then i had to mention the channel .So i tried Dev1/ai0,but it showed that i could not add a physical channel,andthat i had to specify  a virtual channel. So i again followed the same procedure to first define a virtual channel for using it in the place where i had to mention the channel name.However i had to use cjc"constant source" in defining this channel and later i realised that the device was using the constant value that i put in and not measuring the cj temperature itself.

With Regards

Rupak

[RobCole]

Hmmm. I've never had a problem setting up a system with the SCB68 accessory. Since I have no other idea and was given a new computer recently and haven't installed my DAQ card yet, I'll attempt to read between the lines here...

Are you setting up the channel as a virtual channel first and then adding the virtual channel to a task?  Or are you setting up the channel directly in a task?

I was curious because your message seems to indicate that youare setting it up in a task and not a virtual channel first. Our systems all set up virtual channels because you can duplicate them (and sometimes we're dealing with dozens of channels) and then we add them to a task. I know that virtual channels can reference virtual channels, but it is possible that a task can not reference one (as opposed to using one for acquisition). I hope that makes sense.

If you find that it works when set up as a virtual channel first, then kick this back to NI as a bug report. MAX shouldn't let you set up something that doesn't work.

     Rob