4-20mA Calculation

I am using Pressure Sensor 4-20mA and at 10 PSI my multimeter is showing me 5,6mA.I just want to know if this is rite, can somebody please tell me how to calculate this.

thx

I don't know - what colour is it ?

Seriously , you are asking an open ended question- what you state suggests that this is a 100 PSI transducer
((20-4)/(5.5-4))*10 (I hope I got that right after the beautiful essay posted here about this very subject)

But I could be completely wrong - unless I know two points , I can't extrapolate ( put a line) through your data .
This transducer could be 8-20 PSI , and I would be none the wiser without either you reading what it has stamped on the body , or posting a few more readings .

well , if you take the span of a 4-20mA signal , you have 16mA , let us divide this 16 into the span of your device (100 PSI) and we should get the ratio :- 100PSI/16mA= 6.25PSI/mA - now you said that your device gave an output of 5.6 mA at 10PSI lets see if this is OK :-

(5.6mA-4mA)*6.25 = 1.6*6.25 = 10

I reckon that is OK then , but you may want to stick a few more PSI up its kilt and make sure that it is reasonably linear .

10BaseT. said:

well , if you take the span of a 4-20mA signal , you have 16mA , let us divide this 16 into the span of your device (100 PSI) and we should get the ratio :- 100PSI/16mA= 6.25PSI/mA - now you said that your device gave an output of 5.6 mA at 10PSI lets see if this is OK :-

(5.6mA-4mA)*6.25 = 1.6*6.25 = 10

I reckon that is OK then , but you may want to stick a few more PSI up its kilt and make sure that it is reasonably linear .

Click to expand...

Thanks

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