And if it were a diode bridge, the PMMC meter would indeed read 1V, not 0V.cnh1995 said:
A PMMC (Permanent Magnet Moving Coil) measuring instrument is used for measuring electrical quantities such as current, voltage, and resistance. It is commonly used in laboratories and in electronic testing and measuring equipment.
A PMMC instrument works by using a permanent magnet and a moving coil. When a current is passed through the coil, it experiences a force due to the interaction between the magnetic field of the permanent magnet and the magnetic field produced by the coil. This force causes the coil to move, and the displacement is measured and converted to an electrical reading.
Some advantages of using a PMMC instrument include its high accuracy, reliability, and sensitivity. It is also unaffected by external magnetic fields and has a linear scale, making it easy to read and interpret measurements.
There are some limitations to using a PMMC instrument, such as its low power handling capacity and susceptibility to errors due to changes in temperature. It also requires a stable power supply for accurate readings.
To calibrate a PMMC instrument, it is necessary to use a known reference source to check and adjust the instrument's readings. This can be done by comparing the readings of the instrument with the known values and adjusting the instrument's scale if needed. It is important to regularly calibrate a PMMC instrument to ensure accurate measurements.
