Maintenance advice for intelligent remote flow meter

When using a logic pen or an oscilloscope to detect signals, pay special attention to the fact that the probe cannot be touched to both measurement pins at the same time, because the essence of this situation is that a short circuit is formed in the case of power-on, and the instrument may have a bad possibility.

When measuring with a multimeter ohmmeter, do not operate the measurement with live power.

When overhauling the instrument in a humid environment, it is necessary to measure the smoothness of each point on the printed circuit with a multimeter, because the main fault in this case is copper foil corrosion.

When detecting the filter capacitor in the power supply, the positive and negative electrodes of the electrolytic capacitor should be short-circuited first, and the short circuit can not be used to replace the wire to discharge the capacitor, because it is easy to burn the core wire. You can take a 220V, 60 ~ 100W lamp with a lamp lead, connected to the two ends of the capacitor, the bulb will flash when the battery is discharged.

Do not plug and unplug various control boards and plugs. Because in the case of power-on, the plug-in control board will generate a strong induced electromotive force, and the instantaneous counter-attack voltage is very high, which easily damages the corresponding control board and plug.

When inspecting the internal circuit of the instrument, if the contact points of the mounted components and the circuit board are coated with insulating varnish, the parameters of each point can be measured by ordinary hand stitching on the test chart of the multimeter, so as to pierce the paint layer and directly measure each point without large Area peeling paint layer.

When repairing precision instruments and meters, if you accidentally fly a small part, you should first judge where it may fly. Do not look east, turn it over, you can use magnet scanning and line-of-sight scanning to find.

When disassembling and adjusting the meter, the original position should be recorded for recovery.

Don't blindly knock and bump when you are overhauling, so as not to expand the fault, the more you repair it.