Answer / carl_ellis

Installation error - there is insufficient upstream and
downstream straight run piping for flow conditioning.

Failure to understand that all vortex do low flow cutoff at
approximately 10% of flow because there are not enough
vortices formed to produce an accurate flow rate
measurement. Low velocity flow rate in a steam header can
indicate zero flow even when the boiler is operating with
reasonable loads.

Corrosive fluid destroys the thin sensor membranes.

Carl Ellis
Measure First

What is meant by GAP VOLTAGE, in vibration measurement. Normally how much GAP VOLTAGE is set and state the reason.

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give me the formula for analog to digital converter and also d to a converter

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Q1: Consider part of a control loop, which excludes the transmitter, consisting of a process, a controller and a control valve which may be represented by two dead times of 0.5 min each and three exponential lags of 0.8 min., 1.0 min. and 1.5 min. respectively. We wish to express this system as an overall first order plus dead time (FOPLD) model ie gain, time constant and process dead time. (We will see later that this is often done, to simplify controller tuning). For this exercise, gain is considered to be 1.0. (A) If the transmitter is a flow transmitter whose behaviour can be described by a dead time of 0.2 min. and an exponential lag of 0.5 min. in terms of the overall dead time and overall first order lag how can the system behaviour be approximated ? Overall dead time = Overall time constant = (B) If the transmitter is a temperature transmitter with a temperature sensor in a protecting well whose behaviour can be described by a dead time of 0.7 min. and an exponential lag of 15 min. how can the overall system behaviour be approximated now? Overall dead time = Overall time constant =

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2 Answers  

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which type signal come control valve

6 Answers  

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

19 Answers   Honeywell, TCS, TN,

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