Connection of the pressure transmitter to the scxi-1102 module

Dear sir,
we have a differential pressure transmitter whose specifications are as follows:
Excitation:24 Vdc, output:4-20mA.(make: Cole-parmer instrumentation company)
now, we have a NI scxi-1102 and scxi-1520 module with corresponding terminal blocks.
Our question is how to connect this transmitter to the module and to which module? can we connect it to the scxi-1102? And for the excitation what we should do? please explain the detailed procedure for that.
As the excitation is 24 Vdc, i think we have to use 1102 and has to be excited externally.
Since, i m a mechanical engineer and don't have much knowledge of electronics, please explain all the details as simply as possible.
regards...
Lalit.

I am assuming a couple of things here. They are:
The input you are looking at is a slow responding signal ie less than 2 hz. The 1102 has a built in 2 hz filter.
and or the transducer you are connecting to has a slow update rate.
You are using scxi 1300, 1303, or 1308 terminal block to connect to your chassis.
Channel 0 isn't being used.
That being said, in Max, set the gain to 1
input mode to differential
You can do the scaling in Max if you want to.That's what I typically do.
Linear scAle, 1 volt = 4 ma and 5 volt = 20 ma
On your terminal block, connect a 250 ohm precision resistor across Ch 0 in ( pin 96 & 64)
In series with your current loop ( cut the wire of the existing loop)
Connect one end to pin 96 and the other to pin 64.
Put a voltmeter across the input. red lead to 96, black lead to 64
If the reading is negative flip flop the wires. If positive, good guess.
you should be ready to rock and roll.
GB
Greg Bush CLAD

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DjDave,
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Three_SCXI-1102_Thermocouple_Modules.vi ‏189 KB

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Message Edited by Travis G. on 04-18-2006 05:09 PM
Attachments:
MultipleThermocoupleTask.Jpg ‏68 KB

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MV/psi input for SCXI-1102 using SCXI-1308?

Is there a way to physically connect a mV/psi signal to an SCXI-1102 that is also using a SCXI-1308 terminal block? From what I have read, the terminal block can only use a 4-20 or 0-20mA signal, right? I don't see any pins that the terminal block doesn't plug in to to use for the pressure sensor's mV output.
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Solved!
Go to Solution.

Hi FMC_Pumptest,
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Bad reading of thermocouple on SCXI-1102

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Cannot configure SCXI 1102 in parrallel mode

Hi all...
I have a little problem, i have a system made of 3 Daqmx cards : 2 PXI-6254 and 1 PXI-6229. these cards are linked to SCXI modules. The acquisition of the data are done in parrell i.e. the first PXI 6254 is linked to 2 SCXI-1125, the 2nde PXI-6254 is linked to one SCXI 1125 and one SCXI 1102B and the third one is linked to one SCXI 1180 and one SCXI 1102...
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Error -200619 occurred at DAQmx Start Task.vi:6
Possible reason(s):
Measurements: Chassis cannot be used for more than one scanning operation at the same time.
Do only one scanning operation, or combine multiple scanning operations into a single operation.
Can't anybody explain me why ???
Thanks a lot for your futures answers ...

Not necssarily, You can have parallel mode for other SCXI modules while acquiring from SCXI 1102 in multiplexed mode
See this Link

SCXI different Modules Compatability

I am using a SXCI 1000 (4-slot) chassis with one SCXI-1100 module and 3 SCXI-1102 modules. I want to know if I can multiplex a SCXI-1100 moudule with a SCXI-1102 module to one pulg in DAQ board and the other two SCXI-1102 modules into another plug in DAQ board, eventhough all moudles are housed in the same chassis.

Dunty,
Please refer to the following Knowledge Base article for more information.
Can I Use SCXI Modules in Parallel Mode and Multiplexed Mode in the Same Chassis?
http://digital.ni.com/public.nsf/websearch/C94797073B74E51E86256A93005CABFF?OpenDocument
In your situation you are asking to run all four modules in multiplexed mode with two of them being the controlers. Therefore you will have two groups and this is not possible. If you decide to multiplex the SCXI-1100 module with a SCXI-1102 module to one DAQ board then you will have two modules left over. You could set both remaining SCXI-1102 modules to parallel mode or you could set one to parallel mode and multiplex the last module with the first SCXI-1100 and 1102.
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Justin Britten
Ap
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Connection of the pressure transmitter to the scxi-1102 module

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