Brief Introduction This instrument can measure temperature, optical dissolved oxygen, fiber optic turbidity, four-electrode conductivity, pH, salinity, etc. The BQ401 multi-parameter handheld probe can support up to 4 types of probe measurements. When connected to the instrument, these data can be automatically identified. This meter is equipped with a backlight display and operation keyboard. It has comprehensive functions and simple operation. The interface is simple. It can also realize measurement data storage, sensor calibration and other functions at the same time, and it can export USB data to achieve more high-end functions. The pursuit of high cost performance is our consistent pursuit. Features 1) 4 types of parameters measurement, data identified automatically 2) Equipped with a backlight display and operation keyboard. Comprehensive functions and simple operation 3) Several fucntions include  measurement data storage, sensor calibration and other functions 4) Response time of the optical dissolved oxygen probe 30 Seconds, more accurate, more stable, faster and more convenient during testing                                          Waste Water                                                                             River Water                                                                          Aquaculture Technical Indexes

Multi-parameter Sensor Indexes
Optical dissolved oxygen sensor	Range	0-20mg/L or 0-200% saturation
	Accuracy	±1%
	Resolution	0.01mg/L
	Calibration	One or two point calibration
Turbidity Sensor	Range	0.1~1000 NTU
	Accuracy	±5% or ±0.3 NTU（whichever is greater）
	Resolution	0.1 NTU
	Calibration	Zero, one or two point calibration
Four-electrode conductivity sensor	Range	1uS/cm～100mS/cm or 0~5mS/cm
	Accuracy	±1%
	Resolution	1uS/cm～100mS/cm: 0.01mS/cm 0~5mS/cm: 0.01uS/cm
	Calibration	One or two point calibration
Digital pH sensor	Range	pH:0～14
	Accuracy	±0.1
	Resolution	0.01
	Calibration	Three-point calibration
Salinity sensor	Range	0~80ppt
	Accuracy	±1ppt
	Resolution	0.01 ppt
	Calibration	One or two point calibration
Temperature	Range	0~50℃（no freezing）
	Accuracy	±0.2℃
	Resolution	0.01℃
Other information	Protection grade	IP68
	Size	Φ22×166mm
	Interface	RS-485, MODBUS protocol
	Power supply	DC 5~12V, current <50mA
Instrument specifications
Size	220 x 96 x 44mm
Weight	460g
Power supply	2 18650 rechargeable batteries
Storage temperature range	-40~85℃
Display	54.38 x 54.38LCD with backlight
Data storage	support
Air pressure compensation	Built-in instrument, automatic compensation 50~115kPa
Protection grade	IP67
Timed shutdown	support