Converting voltage module to current module

[flyers]

Hi guys,

I'm sizing up a Micrologix 1400 and their base itself comes with 4 AI & 2 AO, but all a voltage type (0-10V), is there anywhere we can change this voltage input & output to current? (4-20mA).

Can we put a resistor across the AI to get current measurement?

Thank you

 

[OkiePC]

No, if they were current outputs you could add a resistor to get voltage, but the reverse won't work.

You probably need to add a signal converter to do what you want.

There are many of these available on the market, some of which are as small as terminal blocks.

One example:
http://www.phoenixcontact.com/signal-level-matching/31244.htm

Paul

 

[Kidblue]

You can certainly use a resistor across the AI (see (one of many) post below)...Typically 500ohm precision resistor.

http://www.plctalk.net/qanda/showthread.php?t=36088&highlight=0-10v+4-20mA+resistor

Hope this helps!

Rob

 

[flyers]

Guys, thanks a lot for the info.

 

[shooter]

the analog inputs can be done with a resistor.
for full you could use 500 ohms with 20 mA it will result in 10000mv is equal to 10 volts.
however in the software you will have to calculate from 2 volts up to 10 volts
0% is 2 volts and 100% is 10 volts


the resistor has to be a little bigger as usual as the wattage is 10 volts times 20 mA is 200 mWatt and that is the max of a small resistor. so find a little bigger and it will work fine.
the output can not make this high current, depends on type of card.
however check if on the inputs you are driving there is a resistor present. if you make it bigger the amps get lower for the output.

 

[Roy Matson]

For typical 2 wire loop you need to bear in mind that a transmitter drops about 11 Volts, 11 + 10 for the input = 21 so there is no room for additional loads unless you boost up the supply voltage over 24 DC
Roy

 

[flyers]

Guys, I'm referring to MLX 1100, the 2 analog points are having the same common 1A, can I put a resistor at [IA COM] & [IV1(+)] for analog input 1 and [IA COM] & [IV2(+)] analog input 2.