Waterproof pH/CON 300 Meter from Oakton Instruments

Waterproof pH/CON 300 Meter from Oakton Instruments

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Waterproof pH/CON 300 Meter

The one meter you need for taking conductivity, TDS, pH and temperature readings in rugged environments!




Waterproof and dustproof housing (IP67 rating) that floats!
Reads pH, conductivity, TDS and temperature in °C/°F
Dual display of measurement plus temperature
Easy push-button conductivity and pH calibration
Auto-ranging for conductivity measurements; Auto-buffer recognition for pH calibration
Features selectable automatic endpoint display to "hold" reading when it is stable for more than five seconds
Selectable Manual or Automatic Temperature
Compensation with separate temperature readout
Easy to clean housing
Hold function; "Ready" indicator; Error messages; Auto-off function

The microprocessor-based OAKTON waterproof pH/CON 300 meter meets IP67 ratings for dustproof and waterproof ingress protection.


Advanced setup mode lets you customize meter parameters, view calibration values for pH and conductivity (TDS), view pH electrode slope for diagnostic purposes, and more. All functions are accessible from the waterproof keypad.

Click below to download Acrobat (.pdf) file of:
pH / CON 300 meter product bulletin
pH / CON 300 meter manual

Measures pH, Conductivity, TDS, °F, °C
pHRange -2.00 to 16.00 pH
pHResolution 0.01 pH
pHAccuracy ±0.01 pH
pHCalibration 5 points (pH 1.68, 4.01, 7.01, 10.01, 12.45)
mVRange -2000 to +2000 mV
mVResolution 0.1 mV ±199.9 mV, 1 mV beyond
mVAccuracy ±0.2 mV ±199.9 mV, ±2 mV beyond
mVCalibration Offset up to ±2000 mV
0.00 to 19.99 µS,
0.0 to 199.9 µS,
0 to 1999 µS,
0.00 to 19.99 mS,
0.0 to 199.9 mS
ConductivityResolution 0.01 µS, 0.1 µS, 1 µS, 0.01 mS, 0.1 mS
ConductivityAccuracy ±1% full scale
ConductivityCalibration Five-point calibration
0 to 9.99 ppm
10.0 to 99.9 ppm
100 to 999 ppm
1.00 to 9.99 ppt
10.0 to 199.9 ppt
TDSResolution 0.01 ppm, 0.1 ppm, 1 ppm, 0.01 ppt, 0.1 ppt
TDSAccuracy ±1% full scale
TDSCalibration one point per range (up to 5)
TemperatureRange 0.0 to 100.0°C
TemperatureResolution 0.1°C
TemperatureAccuracy ±0.5°C
TemperatureCalibration offset 0.1°C increments
ATC manual or automatic from 0.0 to 100.0°C
Power 4 1.5 V AAA batteries, >200 hours continuous use
Memory Up to 16 sets with temperature
Optional AC Power Yes
Built-in Stand Yes
Dual Display Yes
Waterproof/Dustproof (IP67) Yes
Dimensions 7.5" x 3.5" x 1.75" (19 x 9 x 4.5 cm)
Shipping weight 2.0 lb (0.9 kg)

Metex Corporation