Misunderstandings in the analysis of the electromagnetic flowmeter alarm phenomenon

When the user uses the electromagnetic flow meter, there will occasionally be an alarm phenomenon, and the other party will naturally think that there is something wrong with the flow meter? In fact, specific problems must be analyzed in detail. The alarm phenomenon of magmeters often has the following three main misunderstandings:

Misunderstanding 1: magmeter excitation alarm and system alarm are caused by magmeter failure?

System alarm: SYS——system excitation alarm, also called excitation alarm

Actually, excitation alarm and system alarm are the same, sometimes called system excitation alarm, which belongs to intelligent electromagnetic The excitation signal alarm detected by the flow meter intelligently, when the customer encounters such a situation, it is mainly caused by vibration.excessive damage to the line, or an open circuit in the pickup coil caused by water entering the junction box during use.

The solution to the magmeter system alarm:

The solution is also very simple. The user can use a multimeter to detect the on-off of the excitation line to be judged. The specific terminals are EXT + and EXT - these two terminals A, measure whether there is a resistance value, and determine the reason for the excitation line disconnection by judging the resistance value. Specific criteria for judging: the resistance of the excitation coil shall not exceed 200Ω. Another situation belongs to the battery-powered electromagnetic flowmeter. Its excitation alarm is to detect the resistance of the excitation coil. Although the excitation alarm appears, it will not affect the measurement results. Users can solve this phenomene by defining the method of excitation.

Misunderstanding 2: The magmeter empty pipe alarm is the failure of the magmeter?

Empty pipe alarm: FGP—fluid empty pipe alarm

Smart electromagnetic flowmeters usually have the function of empty pipe detection and do not require additional electrodes. When the user selects the empty pipe alarm, when the fluid in the pipeline is lower than the measuring electrode, the smart magmeter can detect an empty pipe condition. When the empty pipe condition is detected, the counter\'s analog output and digital output signals are both 0, and the meter\'s flow rate display is also 0.

The meaning of the electromagnetic flowmeter empty pipe alarm is that the customer can know the flow status of the fluid in the measuring pipe in real time.re, and even the state of the empty pipe and the full pipe. It is particularly suitable for these opaque pipe sections. The fluid inside is convenient and fast, reflecting the humanized and intelligent design of the smart flow meter. Therefore, the electromagnetic flowmeter empty pipe alarm is not a failure of the electromagnetic flowmeter, but a true reflection of the fluid situation in the measurement pipeline. Of course, users can choose to disable this setting according to their needs.

Misunderstanding 3: Are the flow rate upper limit alarm and flow rate lower limit alarm of the electromagnetic flowmeter out of range?

FQH——upper flow limit alarm

FQL——lower flow limit alarm

Upper and lower flow limit alarms are calculated depending on the percentage of range of the flow meter. The parameter concretely reflects whether the usemagmeter exceeds the set range in a specific flow range, and it does not mean that the magmeter exceeds the measuring range, it can only be regarded as the setting of the magmeterThe percentage of the range of the magmeter is underlined here because the electromagnetic flowmeter range can be set, sometimes to improve the resolution of the electromagnetic flowmeter output signal, so for the electromagnetic flowmeter upper and lower limit alarm phenomena, the user can according to the measurement You can set it if you really need it. If you think it is not necessary, you can also choose to close it. It is primarily used for client-specific traffic callback. Specific solutions are as follows:

Upper and lower limit alarms indicate that the output current, output frequency, or pulsewe are all over the limit. After changing the flow range to a larger or smaller range, cancel the upper and lower limit alarms.

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