why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything

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Question Posted / ravi sankar

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why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything..

Answer / suresh

why put 4-20ma na process zero or live zero.

Is This Answer Correct ?

1 Yes

2 No

why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything..

Answer / pradip

*To determine live zero
*To avoid noise
*Linearity is maximum
*Transmission of signal over long distace

Is This Answer Correct ?

1 Yes

2 No

why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything..

Answer / kambiz

why 4ma show higher zero ?
i have transmiter flow renge 0-1000 m3/h but 4 ma show in
monitoring 200 m3/h and 20 ma show 1000 m3/h i want when 4ma
show 0 m3/h and 20ma 1000m3/h

Is This Answer Correct ?

1 Yes

2 No

why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything..

Answer / smruti senapati

with 0-20 ma you canot distinguish between minimum field
value and connection break.with 2-20 ma ,internal circuits
can distunguish between connection break of minimum
value.normally when the value is minimum the transmitter
will give you 4 ma while in case of connection breakage it
will give 0 ma...

Is This Answer Correct ?

1 Yes

2 No

why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything..

Answer / rajesh

As per Numerology 4 is the good number for all analog instruments. next number of 4 is 5. multiply both of them
(4 x 5 = 20).

So only 4 to 20 MA is used in all Analog Signals.

Note: Sorry Friends, i just check whether this website accept all answers or filter.

Don't accept these answers even more no of YES. Because everyone will answer this website without knowing the answer.

Is This Answer Correct ?

0 Yes

3 No

why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything..

Answer / palak m

Why only 4 mA, why not 1,2,3 mA? Because it is universally
tested and approved that at 4 mA the signal has minimal
interference.

Is This Answer Correct ?

9 Yes

19 No

why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything..

Answer / bill

4 milliamp is used as span lower limit, because some
elements on the loop require power from the loop and
therefore a minimum level of power must be available

Is This Answer Correct ?

11 Yes

35 No

why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything..

Answer / imran

The minimum value is 4 mA is because to avoid any confusion
of out put at lowest value.

Is This Answer Correct ?

10 Yes

62 No

why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything..

Answer / saravana

one of reason may be the threshold value

Is This Answer Correct ?

8 Yes

73 No

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