Transmitter settings?
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This post was last edited by “Weak current is still electricity” on 2010-11-1 at 04:31. I’m a beginner; I’d like to ask everyone a question: Is the lower limit of a transmitter equivalent to zero? In other words, if the range of a table is 0 to 25 KP, then is the zero point 0 KP? Suppose I set the range of a transmitter using the terminal handheld device to 0 to 25 KP; then, in the absence of pressure or level, that is at 0 KP, the lower limit output signal should be 4 MA and the upper limit signal 20 MA – is no calibration necessary in that case? If the lower limit is 8MA and the upper limit is 26MA, should I perform negative migration? How can I apply the migrated values to the transmitter? This is what I’m thinking: should we use a terminal handheld device to adjust the range so that it corresponds to 4 to 20 MA? I hope those with more experience can answer my questions one by one. Please do not use copy-pasting; only genuine inquiries are welcome. The younger ones sincerely offer their regards: handshake
The lower limit of the gauge’s measurement range corresponds to 4 mA, while the upper limit corresponds to 20 mA. A gauge with a measurement range of 0–25 KPa does not necessarily have a range of exactly 0–25 KPa; therefore, its zero point is not necessarily at 0 KPa. The assumption you made isn’t entirely correct, because in this case the gauge’s measurement range is set to 0–25 KPa, which allows it to operate within the 4–20 mA range. However, due to differences in installation conditions, sometimes the gauge may show readings even when there is no pressure or liquid level present. In such cases, it’s necessary to adjust the reading back to the zero point. (If the lower limit is 8 mA and the upper limit is 26 mA, should I adjust the value negatively?) I’m not quite sure about that. In any case, to set up the gauge, one first calculates its measurement range and then determines the amount of adjustment needed, which is then set using a handheld controller. Some handheld controllers have automatic zero-point adjustment functions; in such cases, the measurement range can be set first, the gauge’s pressure sensing element can be disconnected and placed in a position where there is no pressure or liquid level, and after the zero point is automatically adjusted, the gauge can be put into use.
Big brother, just answer the question I asked you; don’t say anything else
First, I want to ask if the lower limit is zero? Second, is migration necessary? Third, how can the migrated data be applied to the transmitter? Could you go into more detail on this? Fourthly, this is my thinking: should we use a handheld terminal to adjust the range so that it corresponds to 4 to 20 MA? Fifthly, could you tell me the formulas for calculating the range and for handling positive and negative offsets? Please answer each one
Is the lower limit of the transmitter zero? 0~10mA corresponds to 0, while 4~20mA does not correspond to 0. If the range of a table is from 0 to 25 KP, then isn’t the zero point 0 KP? First of all, the unit is written incorrectly; it should be kPa ； The zero point of the table is 0. Suppose I set the range of a transmitter using the terminal handheld device to 0 to 25 KP; then, in the absence of pressure or level, that is at 0 KP, the lower limit output signal should be 4 MA and the upper limit signal 20 MA – is no calibration necessary in that case? In the absence of pressure and liquid level, the output signal is definitely 4 mA at the lower limit and 20 mA at the upper limit at 0 kPa. Whether a shift is necessary depends on the actual conditions; shifts can be positive or negative. If the lower limit is 8MA and the upper limit is 26MA, negative migration should be performed; migration does not involve changing the range, but rather adjusting the zero point.