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qalood
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Join Date: Mar 2008
Posts: 2

differential pressure level transmitter

03/21/2008 3:31 PM

dear all,

could you please help me to calculate the range of dp level transmitter in the above example?

appreciate your soonest response.

regards,

qalood

distance in mm

6350

4450

6075
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Ace Boeringa
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#1

Re: differential pressure level transmitter

03/21/2008 4:12 PM

An instrument range of 4450 to 6075 mm WC will provide a signal that is proportonal to 0% to 85.55% of level.

With this configuration you will not be able to measure the level when it is higher than the low pressure tap.

Note that water finding its way into the low pressure sensing line will cause a false low indication.
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Vulcan
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#8
In reply to #1

Re: differential pressure level transmitter

03/23/2008 7:46 AM

I agree with Ace Boeringa. Your 100% level is higher than your upper tap (low side) and this will result in a range of only 0 to 85.5%.

If you're using open impulse lines (no seals), you should fill them with either product or a substance that will not mix with the product. Personally, I'd use pressure seals to avoid complications.

If you want to measure up to the 100% level, you should put your low side tap higher than the 6350mm point.

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Steve S.
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#2

Re: differential pressure level transmitter

03/21/2008 4:15 PM

Wow, that screen name makes me wonder what you are processing....
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Mikerho
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#3
In reply to #2

Re: differential pressure level transmitter

03/21/2008 10:56 PM

?

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qalood
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Posts: 2
#6
In reply to #2

Re: differential pressure level transmitter

03/22/2008 8:56 AM

steve s,

could you please explain to me why you are deride???????????????
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Steve S.
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#7
In reply to #6

Re: differential pressure level transmitter

03/22/2008 9:14 AM

Sorry, that was not derision. That was a question.

I am curious why you choose that screen name? It sounds like a very famous pharmaceutical that was very popular in the 60's and 70's for use in getting high.

Which brings me back to the original question, what are you processing that you are trying to get a level on? It might actually impact the measurement.
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Mikerho
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#4

Re: differential pressure level transmitter

03/21/2008 11:08 PM

Hi qalood,

Hope you're up for this.

Your range will be ~250 in H2O abs. or 10 psia.

Please note: Your low side (static) tap should be ported to the vacuum headspace.

Mike

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josej
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Location: Mumbai
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#5

Re: differential pressure level transmitter

03/22/2008 7:53 AM

ASSUMING THAT CONDN DOES NOT OCCUR AND ISTALLED SCHEME IS DRY LEG TYPE

SPAN : 1900*1=1900 MMWC

ELEVATION: 4450*1=4450 MMWC

LRV=4450

URV=6350 MMWC
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Users who posted comments:

Ace Boeringa (1); josej (1); Mikerho (2); qalood (1); Steve S. (2); Vulcan (1)

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