Due to the influence of environment, fluid characteristics and other factors on the measurement site of electromagnetic flowmeter, it is necessary to conduct a field calibration.Below we introduce the method of field calibration.
1. Select the appropriate water pump according to the pipe diameter and flow rate of the verification test;
2. If the system adopts compressed air power, open the air compressor to meet the air source pressure required by the system, so as to ensure the quick switch of the commutator and the normal operation of the meter clamp;
3. After the flowmeter is installed and connected correctly, it should be electrified and preheated for about 30min in accordance with the verification regulations;
4. If high tank water source is used, check whether overflow signal of stabilized water tower appears.Before the formal test, according to the requirements of the verification regulations, the verification medium should be used to circulate in the pipeline system for a certain period of time, and at the same time, check whether the sealing parts in the pipeline have leakage phenomenon.
5. Before formal verification, the verification medium should be filled with the detected flowmeter sensor, and then the downstream valve should be closed for zero adjustment;
6. At the beginning of verification, the valve at the front of the pipeline should be opened first, and the valve after the tested flowmeter should be opened slowly, so as to adjust the flow rate at the test point.