The main points for laying the signal lines of electromagnetic flowmeters. Nowadays, the laying of cables is divided into two types: well-known and concealed. The concealed shop is to consider the electromagnetic flowmeter and other industrial control instrument panels in the design of the factory building. The concrete steel pipe and the seamless steel pipe in the wall are laid in advance. Later, the cable is laid in a seamless steel pipe by a wiring method. Sometimes, it is also processed by the tight combination of cable trench and embedded parts. There are two ways of paving, one is to lay the cable along the wall and the foot of the wall, and then insert the cable inside. This method of electromagnetic flowmeter depends on the details on the spot.
Generally there are two cables between the electromagnetic flowmeter converter and the transmitter. One is the power plug of the converter showing the exciting current switching power supply to the transmitter. One is the ground signal line that the transmitter wants the converter to output. In order to reduce the impact of AC power on data signals, it is stipulated that the signal line and the power plug are respectively laid in two seamless steel pipes, and it is not necessary to lay in another seamless steel pipe. For the LD wastewater electromagnetic flowmeter and LD-F type electromagnetic flowmeter, a cable for transporting the electromagnetic field compensation magnetic coil magnetic induction data signal or the switching power supply voltage transformer output data signal must be upgraded between the transmitter and the converter. At this time, this cable can be laid in the same seamless steel pipe as the excitation current power plug.
Converter output specifications When the output terminal of the AC current is not externally connected, the output terminal should be short-circuited. Otherwise, the converter indicates that the watt-hour meter is short-circuited and not marked. When externally marking, recording, accumulating, and manipulating the dashboard, they should be connected in series. Pay attention to the optical rotation of the AC current, and it is required that the output load does not exceed 2 kiloohms.
Pay attention to the following when wiring the electromagnetic flowmeter:
1. Be sure to connect the transmitter and converter with the complete set of equipment according to the standard of the matching number of the transmitter and converter, and strictly connect the wires according to the wiring diagram.
2. The signal line should be prevented from paving in parallel with the driving force line of large current
3. If it is equipped with a switching power supply, an automatic switch and a fuse should be installed, and a display lamp should be provided when necessary.
4. After the wiring is completed, the threaded sleeves of the transmitter and converter out-of-boundary holes should be tightened to make them tight. Avoid the intrusion of moisture and harmful substances.