Joe McGivern
New Member
I have recently had a situation where I needed to change the analogue current signal output from an instrument from 4/20 mA to 1/5 volts to suit the input to another piece of equipment.
There are converters for this purpose and are readily available for those who have the cash and know where to look.
While doing some tests I had an accident and caused irreparable damage to the converter. I needed a quick fix and connected a 250R resistor across the terminals where the voltage signal was to be connected. By connecting the 4/20 current signal through the resistor it created the desired effect ,ie 1 to 5 volts depending on the level of the current flowing.
It seems to work perfectly but I am concerned that there will be a detrimental effect to either one or other instrument in the long term.
The purpose built converter has several options which make it adaptable to suit other circumstances but "my shortcut" works
If any one can understand what I am doing please comment.
Regards JMcG
There are converters for this purpose and are readily available for those who have the cash and know where to look.
While doing some tests I had an accident and caused irreparable damage to the converter. I needed a quick fix and connected a 250R resistor across the terminals where the voltage signal was to be connected. By connecting the 4/20 current signal through the resistor it created the desired effect ,ie 1 to 5 volts depending on the level of the current flowing.
It seems to work perfectly but I am concerned that there will be a detrimental effect to either one or other instrument in the long term.
The purpose built converter has several options which make it adaptable to suit other circumstances but "my shortcut" works
If any one can understand what I am doing please comment.
Regards JMcG