PH/ORP measuring instrument

The utility model discloses a pH/ORP measuring instrument which comprises a measuring instrument main body, a processor, a pH/ORP analysis rod and a light alarm, the processor comprises a first alarm output end used for outputting an alarm signal during alarm; the light alarm comprises a first LED lamp, a first NPN type triode, a first resistor, a second resistor, a third resistor, a grounding end and a power supply end; the first alarm output end is electrically connected with one end of the first resistor; the other end of the first resistor is electrically connected with the grounding end through the base electrode and the emitting electrode of the first NPN type triode in sequence, and is electrically connected with the grounding end through the second resistor; the power supply end is electrically connected with the collector electrode of the first NPN type triode through the third resistor and the first LED lamp in sequence; a light-transmitting area is arranged below the operation keys on the front sid