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Note on the laying of the electromagnetic flowmeter signal line

Cable laying is now divided into two types: name shop and dark shop. The dark shop is to consider the electromagnetic flowmeter and other industrial control instruments in the design of the plant. The steel pipe for laying the cable is pre-embedded on the concrete floor and the wall. Then use the threading method to lay the cable in the steel pipe. Sometimes it is solved by a combination of cable trenches and pre-buried. There are two ways to open the shop. One is to lay the cable along the wall and the corner, and then wear the cable inside. These methods of electromagnetic flowmeter depend on the specific conditions of the site.

There are usually two heel cables between the electromagnetic flowmeter changer and the transmitter. One is the power cord that the converter supplies to the transmitter with an excitation power supply. One is the signal line that the transmitter wants to output from the converter. In order to reduce the interference of the AC power supply to the signal, the signal line and the power line are required to be respectively laid in two steel pipes, and not to be laid in one steel pipe at the same time. For the LD sewage electromagnetic flowmeter and the LD-F electromagnetic flowmeter, a cable for transmitting the magnetic field compensation coil induction signal or the power transformer output signal is added between the transmitter and the converter. At this time, the cable can be laid in the same steel pipe as the excitation power cord.

The output of the converter outputting standard DC current should be shorted when there is no external load. Otherwise the converter indicates that the meter is open without indication. When externally instructing, recording, accumulating, and controlling the instrument, they should be connected in series. Note the polarity of the DC current and specify that the output load does not exceed 2 kΩ.

The following points must be noted when wiring the electromagnetic flowmeter:

1. When wiring, it must be connected according to the principle that the transmitter and the converter are matched.

2. The signal line should be avoided as parallel as possible with the high current power line.

3. Configure the power supply, you should install the control switch, fuse, and if necessary, you need to configure the indicator light.

4. After the wiring is completed, the screw sleeve of the transmitter and the converter outlet hole should be tightened to seal it. Prevent the intrusion of moisture and harmful gases.

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