R/I converter

Any chance of a digital picture?

unfortunatly no but i gaus it's type of ommeter convert from ohm to current

The question is a bit vague. But.

The position of something could change a resistance. The resistance value is then converted into a form that can be read by a PLC. eg A dancer arm position can be fed into the 4-20mA inputs of a VSD, to trim linespeed.

Throw it into the draw, it may come in handy someday. Jeff

R/I converter is Resistance to current converter. In your case when the resistance of the slide wire is 100 ohms the current will be 4 mA, and when the resistance is 10000 ohms the current will be 20 mA , in between the current output will be proportional to the resistance. . More details are required about the exact application.

Not really knowing wether you HAVE or you WANT a schematic - you may look at TI.COM at the XTR101 - XTR117 series to get an idea of how these converters work and can be applied.

Good luck
Uwe

In these Control-Topology the controls values used are to vary the output value from min to max by:

1. 4-20 mA

2. 0-20mA

3, 0-10 V

4. (-)10 -0- (+) V

5. 0-10KΩ

etc etc

Almost in majority of Control-values a Variable resistor is used to Vary the Output values fom min to max.

Actually the Input to R/I or R/V converters is the variable voltage varied thru var resistor. It is normally multi-turn.

Well, it is resistance to current converter. Usually it is use as a positioner, the slide is mechanicaly link (linkage) to a valve opening ang closing, or a linear mechanism to and pro.

Converter alone is not enough. the control Loop includes your controller in which reads your 4-20 mA from your converter as a min max position, your controller has also an output, defending on the input of the actuator you need, 4-20 mA, 0-20 mA, 0-5 V, 0-10 V etc, the actuator converts the electrical signal to mechanical action, from 0 - 100 % actuation.

Now a days it not only connected to actuators, connected to PLC and do a multi task job, control speed, volume, heat anything you can measure.

Available this days were positioner using infra-red, laser to achieve a high degree of control.

This control loop are the heart of most of the industrial processes if no all.