how to connect 2 wire sensor to DAQ

[Grugh_Mike]

I need to connect a 2 wire and 3 wire sensor to the NI PCI 6514 DAQ board.

How do i do that?

Will the sensor work if i connect one wire to the input port and the other wire to the corresponding COM port? (ex. P0.0 and P0.COM)

What is the solution in case of 3 wire sensor ? i have no clue on this...where should i connect each wire to?

Kindly help me out.

Its urgent.

[GerdW]

Hi Mike,

you better read the manual of your sensors. They usually explain how to connect them...

2-wire-sensors commonly use the current as signal, while 3-wire-sensors usually use power supply for 3rd wire and give a (ratiometric?) voltage signal on "middle" pin...

P0.0 seems to denote a digital input - it can be tricky to use an analog sensor with that input!

[Grugh_Mike]

Dear GerdW

Thank you for the reply.

I read the manual--> I am using the proximity sensor from FESTO SME-8-K-LED-24

It has three wires, blue, brown and black.

It should be connected to the 6514 card.

If i am using bank 0; then the P0.0 and P0.COM will my required pins.

Will it be ok of i connect brown and black to P.COM and blue to P0.0?

Kindly advice.

Also what should be the required rating of P0.COM to be supplied external ?

Will a 24V, 1.42A DC supply be ok?

Kindly help.

[GerdW]

Hi Mike,

well, there are schematics in the manuals - ot hard to find that information...

brown = +voltage

black = P0.0

blue = ground

For your P0.0 input you should use a supply of 5V (TTL-compatible), propably available on your card. Connect the supply voltage with your brown wire. (Maybe switch to the P6 or P7 bank, as they provide 5V!) Maybe you will need a pullup or pulldown resistor to assure clear voltage potential

when the FESTO switch is open.