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Anonymous Poster

4-20mA

12/08/2009 10:52 PM

Hello,

What will happen if I use 1 pair instrumentation cable to supply 2 transmitters (4-20mA)??
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PWSlack
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#1

Re: 4-20mA

12/09/2009 3:52 AM

Nothing useful will come out of the cable at the receiving end.

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porky2009
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#2

Re: 4-20mA

12/09/2009 4:24 AM

what would be the point in that ??? how would you connect the transmitters in parallel or in series ? weird question !!

Do you not mean a valve positioner ??
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jcchiefeng
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#3

Re: 4-20mA

12/12/2009 10:52 PM

Is the cable providing power to the transmitter or is the cable returning a 4-20mA signal from two sources?

1. If power, nothing. This will be fine to supply the transmitters with power from the same source if 4-wire transmitters. It should not be used with multiple two wire current loops.

2. Never could you share the signal from two transmitters on one pair of wires.

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