When the user uses the electromagnetic flow meter, there will be an occasional flow meter alarm. People will naturally think of whether the electromagnetic flow meter is malfunctioning when it is working. In fact, specific problems need specific analysis. The alarm of electromagnetic flow meters often has the following three misunderstandings:
SYS: also called excitation alarm, which belongs to the flow meter alarm of the excitation signal detected by the smart electromagnetic type flow meter. When the customer encounters such a situation, it is mostly due to excessive pipeline vibration, or in the course of use, the junction box is exposed to water and damp, causing the excitation coil to open.
The solution of flow meter problems to the system alarm when the electromagnetic flow meter is working: The solution is also very simple. The user can use a multimeter to detect the on-off of the excitation circuit to judge. The specific terminals are EXT+ and EXT. The two terminals measure whether there is a resistance value and judge the resistance. The value is used to determine the reason for the disconnection of the excitation circuit. Specific criterion: The resistance of the excitation coil will not exceed 200Ω. There is also a battery-powered electromagnetic flow meter. Its excitation alarm is detecting the resistance of the excitation coil. Although an excitation alarm will appear, it will not affect the measurement results. Users can solve this type of phenomenon by setting the excitation method.
FGP: It refers to an empty pipe alarm. As one of the flow transmitter types, smart electromagnetic flow meters generally have FGP function, and no additional electrodes are required. When the user selects the FGP, when the fluid in the pipe is lower than the measuring electrode, the smart electromagnetic flow meter can detect an empty pipe state. When the empty pipe state is detected, the analogue output and digital output signal of the instrument are 0, and the flow rate display of the meter is also 0.
According to the electromagnetic flowmeter working principle, the significance of the FGP when the electromagnetic flow meter is working is that the customer can know the flow state of the medium in the measuring pipe in real time, even the empty pipe or full pipe state, especially suitable for those opaque pipe sections, it is the most convenient and quick for users to judge the fluid in the pipe, which embodies the humanized and intelligent design of the smart flow meter. Therefore, when the electromagnetic flow meter is working, FGP is not that the electromagnetic flow meter is malfunctioning, but that it faithfully reflects the fluid condition in the measurement pipeline. Of course, users can choose to prohibit this setting as needed.
FQH refers to high flow alarm FQL refers to low flow meter alarm. The high and low flow alarms are calculated according to the percentage of the flow meter's range. This parameter reflects whether the specific flow range exceeds the set range. It does not mean that the electromagnetic flow meter exceeds the measurement range, but can only be regarded as a percentage of the range set by the electromagnetic flowmeter. The setting is emphasized here because the range of the electromagnetic flowmeter can be set. Sometimes it is to improve the resolution of the output signal of the electromagnetic flow meter. Therefore, for the high and low flow alarm of the electromagnetic flow meter, the user can set it according to the actual needs of the measurement. If you think it is not necessary, you can also choose to close it. It is mainly used as a reminder of the customer's specific flow.
The specific solutions are as follows: FQH and FQL indicate that the output current and output frequency or pulse are all over the limit. After changing the flow range to large and small, the high and low flow alarms are cancelled.