DIGITAL MULTIMETER WITH MISOPERATION PREVENTING FUNCTION

摘要

The present utility model provides a digital multimeter that can not only; generate warning signal when the test probe is misplugged but also indicate the assigned socket before the probe is plugged in. The multimeter contains a socket indicating and misplug warning circuit whose micro- control unit is connected with each measurement function switch via its terminals respectively. When any measurement function switch is closed and its corresponding socket is unclosed, the microcontrol unit switchs on the relevant LED to emit light via connected terminal in order to Indicate the assigned socket. On the contrary, the microcontrol unit switchs off the LED to stop emitting light in order to indicate the proper operation. The multimeter can indicate not only misoperation after the probe has been plugged in but also the assigned socket before it so that it decreases the possibility of misoperation and avoids damage effectively and elongates its working life.