The digital voltmeter has to be powered with a power supply or batteries, while the magnetoelectric type meter only needs a battery in the ohms mode.
The digital voltmeter has to be powered with a power supply or batteries, while the magnetoelectric type meter only needs a battery in the ohms mode.
数字式伏特计必须供以能量或者以电池组为动力,而磁电式仪表仅仅在欧姆表里需要一节电池。