Instrument and meter maintenance items

1. When using a multimeter to ohmic block, remember not to perform live measurement. 2. When using a logic pen or oscilloscope to detect signals, be careful not to make the probe touch the two measurement pins at the same time, because the essence of this situation is to form a short circuit when the power is turned on. 3. When testing the filter capacitor in the power supply, the positive and negative electrodes of the electrolytic capacitor should be short-circuited first, and do not use the test lead wire when short-circuited. 1. When using a multimeter to ohmic block, remember not to perform live measurement.　　 2. When using a logic pen or oscilloscope to detect signals, be careful not to make the probe touch the two measurement pins at the same time, because the essence of this situation is to form a short circuit when the power is turned on.　　 3. When detecting the filter capacitor in the power supply, the positive and negative electrodes of the electrolytic capacitor should be short-circuited first, and do not use the test lead wire to replace the lead to discharge the capacitor during the short circuit, because it is easy to burn the core wire. You can take a 220V, 60-100W lamp with a lamp cap and connect it to both ends of the capacitor. The bulb will flash at the moment of discharge.　　4. When inspecting and repairing instrument faults in a humid environment, it is necessary to use a multimeter on the printed circuit to test whether the points are unobstructed, because the main fault in this case is the corrosion of the copper foil. 5. When inspecting and repairing the internal circuit of the instrument, if the contact points of the installation components and the circuit board are coated with insulating varnish, when measuring the parameters of each point, you can weld the test pen of the multimeter with a common hand stitch to pierce the paint layer and directly measure each point. There is no need to peel off the paint over a large area.　　6. u200bu200bDo not plug and unplug various control boards and plugs with power on. Because when the power is on, plugging and unplugging the control board will generate a strong induced electromotive force. At this time, the instantaneous counterattack voltage is very high, and it is easy to damage the corresponding control board and plug.　　7. Do not blindly knock and touch during maintenance, so as not to enlarge the fault, the more the repair, the worse.　　 8. When disassembling and adjusting the meter, the original position should be recorded in order to restore it. 9. When repairing precision instruments and meters, if you accidentally fly small parts, you should first determine the place where they might fly. Don't look for it or turn it around. You can use magnet scanning and line-of-sight scanning to search. In short, in the maintenance of instruments and meters, we must first understand the basic principles of instruments and meters, and master the knowledge and skills related to electronics, and we should prepare all instrument manuals, drawings and other technical materials. In addition, we should develop a Good work quality, thereby improving efficiency and reducing errors in the maintenance of instruments and meters.