Can a pointer multimeter measure AC current?
There are two ways of shunt: first shunt and then rectify, or first rectify and then shunt.
1, the difference between rectification and shunt sequence
When shunt first and then rectify, the current flowing through the rectifying element is smaller; while rectify first and then shunt is equivalent to the measured current all through the rectifying element, which makes the range of the AC ammeter limited by the permissible current of the rectifying element, and thus this method is less frequently used.
2,Commonly used rectifier AC ammeter circuit
The circuit of the two end voltage will change with the range changes, and at the same time, due to the rectifier element, making the AC ammeter internal resistance increases, which is the shortcomings of the resistance shunt circuit.
How to measure resistance with a multimeter and read the resistance number
In the repair of electronic circuit boards, circuit boards, its resistance components account for about 50% of the entire electronic components, if the circuit has a fault resistance components is one of the components we want to measure.
So how to use a multimeter to measure resistance and read the number of resistance? Below I give you the problems in this regard, before measuring resistance we had better carry out two zeroing operations, one is the pointer multimeter mechanical zeroing; the second is the ohm zeroing. After the operation of these two steps you can choose the appropriate resistance multiplier for resistance measurements, due to the multimeter resistance file scale is not uniform, we choose the multiplier file generally want to make the pointer scale stays in the sparse part of the scale is the best, and the closer the pointer is to the middle of the scale position the more accurate. I suggest that it is best to make the pointer in the scale of 1/3 to 2/3.
Reading Methods
The method of reading the multimeter is not complicated, that is, the reading of the meter head is multiplied by the multiplier, that is, the resistance value of the resistor to be measured. For example, to measure the resistance value of a resistor is 47 ohms, then the range to "Rx10" on the ohms file, then Hou multimeter pointer points to the position of 4.7, the final reading is 4.7x10 for 47 ohms. If the measurement of large resistors can choose a larger resistance range, such as Rx1k or Rx10K, they read the resistance value of the same method.
