Regarding differential pressure level gauges
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The new Yokogawa differential pressure level gauge installed in the unit is used to measure the level of a small storage tank; the pressure is taken from the pressure guide tube. However, the transmitter is installed about 20 centimeters higher than the point where pressure is taken from the positive pressure side. Will this have an impact on the measurement? If there is an impact, how should it be set? Do you need to migrate? How should it be calculated? Solve your doubts!
It’s not a double-flange type; a pressure transfer tube can be used directly (provided that there is no water, isolating fluid, or other pressure-transmitting substances inside). No migration processing is required – just ensure the zero point is set accurately
It’s usually lower than the pressure tapping point; can’t it be changed?
The transmitter should be below the positive pressure tap; otherwise, when the liquid level is below the transmitter, accurate measurement cannot be achieved.
“The installation position of the transmitter is indeed about 20 cm higher than the positive pressure sampling point. The installation location of the transmitter serves as the zero point; as a result, the measurement range will be reduced by 200 mm of static pressure. It is necessary to recalibrate the zero point and the measurement range of the transmitter. If there is a standard water column on the negative pressure side, negative migration will occur, with the amount of migration equal to the static pressure of that standard water column on the negative pressure side of the transmitter.