NI 9205 for passive sensor

[shohag.mech]

Hello

I am using the Module NI 9205 with a NI cDAQ 9188. I have 7 sensors to connect to the module, among those 3 are passive sensors and rest of the sensors are active sensors. I am using differential connection which makes my 32 channel module to 16 channel. I have already connceted 4 active sensors to my module which are currently working fine but I am confused about the passive sensors. Do I need to follow the same connection diagram that I did for the active sensors to get reading from the passive sensors. I just need the connection diagram for the passive sensors to the module NI 9205. Any help in this regard will be highly appreciated.

RAKIB

[Henrik_Volkers]

It would be helpful if you tell us the type of sensor? Link to datasheet? Needed  resolution, bandwidth, ....

[TheEngineeringBear]

It all really depends on what you are doing/wanting fromt he passive sensors.  They should have wiring guides that will explain what you need from them connectin wise.  Here is a good white paper on different wiring conditions and expains a setup for Differential Grounded and Floating setup.

Field Wiring and Noise Considerations for Analog Signals

Also, could you explain what you mean by passive vs. active?

- Bear

[shohag.mech]

I have gas flow sensor and pressure sensor which doesn't require external excitation. Those sensors (Active) take the required power through the module but other sensors (passive): electrical conductivity and desity requires external excitation (power source).  So far thats what I know about the active and passive.

[Henrik_Volkers]

Again: It will depend on the type of sensor.

Your 9205 read voltages (ignoring the 75µA @2.1-3.3V PFI output 😉 )

So you will need something that will convert your 'passiv' output into a coresponding output voltage you can measure. 

A TEC, TC , dynamometer, sensing coil or solar cell ligth sensor can output a voltage, a RTD or switch will need an additional source.

IF you know the sensors  your questions can be answered. (And it would be of great help to help you if you add a link or post the sensor datasheet!)

[TheEngineeringBear]

Are you working with LabVIEW and/or NI MAX?  If working with MAX, you can create the channels the sensors will be on and then see how MAX tells you to configure and wire them.  Between the paper sited above and the datasheets on the sensors, you should have all the information to wiring up the sensors to the DAQs.  A quick google search should be able to find the datasheets if you don't have them.