Problem of small signal rejection in steam flow measurement using flowmeters

This post was last edited by supersuboy on 2012-7-20 08:22. Small-signal rejection is required, for example, 5% rejection. It can be achieved through modification; protocols that support Hart can be modified using a handheld controller

What was said upstairs is correct; 5% is a suggested value, and this value can also be determined based on the specific conditions of the operation.

When using an orifice plate to measure steam flow, how should the small-signal cut-off value be selected?

This post was last edited by hjbjl on 2012-7-17 15:11. Strongly oppose the notion of \"interference\". . . Question: Is low-temperature signal rejection available? Can low-pressure signals be removed? Is small-signal current rejection available? Can low battery signal clipping be enabled? . . . . . . . . . Is it perhaps because of the special nature of traffic that interference occurs and monopolies arise? ! Is it perhaps because of the special nature of traffic that interference occurs and monopolies arise? ! Is it perhaps because of the special nature of traffic that interference occurs and monopolies arise? !

Since flow rate is proportional to the square root of the differential pressure, if the differential pressure is 2%, then the flow rate will be √2% = 14.14%. Therefore, when the flow rate is very low, errors in the flow rate indication can be significant due to the errors in the differential pressure gauge.

The small-signal cut-off for orifice plate flowmeters should be as low as possible; we generally use 1%.

Why use an orifice plate for measurement? Isn’t a vortex flow meter better? ? ?

1. “A differential pressure of 2%” corresponds to a flow rate of “√2% = 14.14%”. This is not an issue related to measurement errors in the differential pressure gauge! Rather, the use of the mathematical relationship √2 is overly forced, which leads to severe distortion in the amount of computation required for low-flow, low-signal conditions, and poses a serious theoretical flaw 2. Small-signal trimming is an engineering approach taken when the errors are too large to be resolved properly, forcing rough compensations; it is an unsightly method that lacks mathematical modeling support. 3. After decades of practical application, there have been endless debates and numerous problematic cases; this approach lacks depth and sophistication in thinking, relying on conventional methods. How can precise measurement be achieved in such a situation? ? ? ? ? ? It can only be a game, a dream – an illusion and delusion. In the 2010s, instrument designers and instrument application engineers, you all hold master’s and doctor’s degrees; you ought to have a moral and scientific responsibility to re-examine and reassess certain measurement theories 4. To provoke further discussion: Russia is nothing but a worthless, contemptible country. In my opinion, the relationship between pressure difference and flow rate should at least be redefined and studied using a polynomial formula: Y=A0+A1X+A2X^2+A3X^3

√Can the equation 2% = 14.14% hold?

The differential pressure transmitter, which supports HART, can be isolated at the gauge head or within the DCS system.