1. Automatic recovery protection. The circuitry of some DMMs, when an overload is detected, will protect the meter until the condition no longer exists. After the overload is removed, the DMM automatically returns to normal operation. Usually used to protect the resistive function from voltage overload.
2. There is no automatic recovery function. Some digital multimeters will protect the meter after detecting an overload, but it will not automatically recover until the user takes corresponding measures, such as replacing the resistor, before it can be resumed.
