Maintenance method of MF47 multimeter
Maintenance method of MF47 multimeter
It's not that the meter is broken! Because "use the 50V AC file to measure the voltage of 220V, and the needle will deflect". If the watch head is broken, the watch hands will not deflect
How to repair the resistance gear pointer of mf47 multimeter
If the pointer multimeter can measure other measurements, but the pointer of the resistance gear does not move, you should check:
1. The resistance gear band switch is in poor contact.
2. The adjustable resistor (zero-adjustment fine-tuning, and some wire-wound fine-tuning) is short-circuited.
3. The shunt and step-down resistors are desoldered or burned.
The following is the circuit schematic diagram of the multimeter:
Maintenance of mf47 multimeter
Friends, it is very likely that you mistakenly use the 10K or 1K range of the resistance range as the voltage range when measuring the voltage and burn out the internal circuit of the multimeter. You have to disassemble and check the current limiting resistor and the diode part of the circuit.
Maintenance of MF47 multimeter head Maintenance method of MF47 multimeter
MF47 Multimeter Maintenance
Turn on the multimeter and see if there is any abnormality or odor on the wiring and components on the circuit board inside. It is estimated that some components inside are broken! It is very likely that the resistor is burned or a component is broken down.
Did you switch the gear of the multimeter when measuring the 5A current?
When the multimeter is measuring a certain amount of electricity, it is not possible to change gears while measuring, especially when measuring high voltage or large current, more attention should be paid. Otherwise, the multimeter will be destroyed.
It must be that some components are burnt out, such as diode breakdown, resistor device open circuit, or triode linearity deterioration, etc. Many of these electronic components are damaged and cannot be seen with the naked eye.
I haven't done anything specific about the circuit board of the multimeter, so I can only offer these opinions! sorry!
Maintenance of mf47 multimeter, any resistance gear and two test leads are connected, and the test needle does not move, how to repair it?
Hey! If you have both the voltage and current files and they are all good and accurate, then you should replace the battery first. Most of the time, the battery is dead or the battery is not installed (including the battery wiring is rusted, which is the most common failure). Otherwise, you can check whether there is a resistance close to the center value of the meter on the 1K file. If not, you should check the voltage file and current file first. Is the internal fuse (specific to MF47) burned, and the meter coils are all broken?
