(3) when you turn on the measuring instrumentPut in place must not have any coercive force. And turn near the magnet from the magnetic field at the time is set to 0, the exact numbers cannot be measured.
③ when turning on the power to the instrument, please put in the not necessarily place the magnetic force. When you turn in the vicinity of the magnet, it can not force 0 is set to measure the exact number from at that time.
When you put the power of measuring instrumentPlease do not put in the place of the magnetic force. Tags: near the magnet can not be accurately measured value is set to 0 when out of the magnetic force.