Measuring 220V with a multimeter only shows 107V What's the reason?
In this case, you should disconnect the power to investigate the cause in detail. It can be measured elsewhere at someone else's house to see if it is normal. Normal should be around 200 to 240 volts. In rural areas it can be as low as about 160 volts at peak times during summer irrigation. This is due to the power supply system. If you measure elsewhere in other people's homes is normal, alone home or one of the way is not normal, that is a fault, should be eliminated before the power supply. To prevent fire damage to electrical accidents. Focus on detailed view of whether poor contact, electrical faults, electrical heavy-duty wire is too thin overload and other reasons. It is best to ask the master electrician to help eliminate. To prevent the expansion of the fault injury damage.
One may be outside the line because the zero line is broken, two, can be used to determine the light and dark pen, three multimeter internal battery is insufficient, take another multimeter for comparison!
First of all, is not the same multimeter in the same total power supply A single-phase line measured the beginning of the voltage 220V, but in the B single-phase line measured the beginning of the voltage 107V? The second question is whether the same multimeter at the beginning of the single-phase line A measured voltage is 220V, but measured at the end of the voltage 107V?
If the same multimeter to measure the same total power supply A single-phase line measured the beginning of the voltage is 220V, and measured B single-phase line voltage is 107V; then B single-phase line line circuit breaker (switch) of the upper and lower ends of each of the two junction should be the existence of oxidation and poor contact resulting in increased contact resistance caused by the voltage drop.
If the same multimeter to measure the same power supply A single-phase line or B single-phase line measurement of the beginning voltage is 220V, and measurement of the end voltage is 107V; then it should be measured that the end voltage of 107V of the line is too long or the line on the line load current is greater than the safety of the line conductor load capacity resulting in voltage drop.
If the same power supply A and B single-phase line measured at the beginning of the voltage is 107V; then it should be the low-voltage distribution area of the distribution transformer's capacity is much smaller than the user's capacity, or the distribution transformer from the user's distribution line is too long and too small to cause voltage drop.
