First recall the failure phenomenon of the stainless steel electric heating tube, and what are the obvious characteristics; secondly, observe whether there are intuitive failure points from the surface, and then proceed to the next inspection:
Shake the meter to detect whether the heating tube is leaking
Shake the meter, that is, the resistance meter to detect the heating tube. When using the shaking table to detect electric heating tubes, we are accustomed to connecting one end of the shaking table to the heating tube terminal and the other end to the heating tube shell, so that the result can be detected. In fact, it is not: before using the shaker, the shaker should be kept in a horizontal position, and the wiring must be correct (the shaker has 3 terminals L, E, G. The L end is connected to the exposed conductor of the loop, when measuring the loop's ground resistance; E When measuring the insulation resistance of the circuit by connecting the first end and the end of the loop to L and E respectively, when measuring the insulation resistance of the cable to prevent the leakage current of the cable from affecting the measurement accuracy, when measuring the insulation resistance of the cable, the insulation resistance of the cable should be measured. The shielding layer is connected to the G end) Press the body of the watch with the left hand, and shake the handle of the watch with the right hand. The speed of about 120r/min and the pointer should point to infinity (∞) is normal, otherwise the heating tube is faulty. Therefore, remember not to connect the wires randomly when detecting the leakage of the heating tube. Do not touch the terminal of the shaker and the circuit under test with your hands during testing, and finally. To prevent electric shock; after shaking the meter, the terminals cannot be short-circuited to avoid damage, and the time should not be too long.
The multimeter detects whether the heating tube is leaking
1. First disconnect the main isolation switch of the user's power supply line, and turn off all the user's electrical loads.
2. Put the gear of the digital multimeter on the 200M gear of the ohm gear, place one test lead on one of the two lead wires on the load side, and the other test lead touches the wall, it is best to touch the ground wire or temporarily Ground wire. After the number displayed on the multimeter is stable, the insulation resistance value of the main circuit is read. If the insulation resistance value is less than 0.5 megohm, then there is a problem with the main circuit. If the insulation resistance is above 0.5 megohm, it can be ruled out There is a problem with the main line. Use the same method to measure another wire, and also check the value to see if there is a problem with the main circuit.
3. Check the insulation resistance of the shunt and each electrical appliance, and use the same method to check one by one until the fault point is found.
Precautions for operating the universal meter:
1. When using the 200M block of the ohmic block of the multimeter, be careful not to touch the metal part of the test pen with your hands during measurement, otherwise the reading will be inaccurate.
2. When measuring various electrical equipment, be sure to discharge first to prevent the capacitive current in the electrical equipment from hurting people.
This method is a safer way to find the fault point in the absence of electricity. However, when searching, it is necessary to disconnect not only the power supply line, but also the neutral line to avoid electric shock accidents.
The heating tube is leaking. If it is to measure whether an object is electrified (electricity to the ground), turn on the multimeter to the appropriate range (depending on the situation), black and white ground, and the red test pen connected to the object under test. If there is an indication, it means that The object has electricity to the ground. If it is to measure whether there is electrical leakage to the ground wire, then measure whether there is current in the ground wire. If it is a clamp meter directly clamp the ground wire to measure, if it is an ordinary multimeter, then you have to cut off the ground wire, open the AC current position of the multimeter (be careful, after cutting the ground wire, the protection of the metal shell electrical appliances will be lost), and both ends will be disconnected Connect it to the two test leads of the multimeter, if there is a reading, it means there is leakage.
The instrument detects whether the heating tube is leaking, and then analyzes whether it is repaired or replaced according to the detected results to finally solve the problem. Various problems may arise in daily industrial use. We are willing to communicate, discuss, and solve problems with customers.
