Clamp multimeter DC party current can not always show zero
The advantage of the clamp meter is that it does not need to move the circuit wiring when measuring the current. AC clamp meters use transformers, while DC clamp meters use Hall elements. The Hall element is affected by the environmental magnetic field (including the earth's magnetic field), and the reading is often in a state of change. Even when measuring, the reading will change when the angle of the watch is turned. AC clamp meters with transformers do not have this problem. Of course, this is only in the case of a small current, after all, the strength of the environmental magnetic field is not very large. The accuracy is still good at high current.
