Low Level (ppb,ug/ml) DO Meter

The TOA DO-32a low density Dissolved Oxygen meter is designed for very low level measurement of dissolve oxygen down to the part per billion level (ug/L). Generally, trace oxygen level monitoring is required in steam and cooling waters for power generation stations, metal corrosion test facilities, atomic power generation stations, production facilities for semi-conductor manufacturing, and other related industries.

The DO-32 can be used for field monitoring or real time control of water quality using its superior electrode system and flow thru cell assembly.

The unit is battery operated and incorporates a membrane based polarographic cell for water quality monitoring of rivers and lakes. It is also well suited for Dissolved Oxygen management in BOD waste water treatment tanks, or culture ponds or other marine environments.

The unit provides pressure (water pressure) and salinity compensation with temperature compensation and offers truly reliable data.The DO-32a is easy to use with a simple one touch air and automatic calibration. This field portable unit is compact, light weight, and water resistant.

Low Level (ppb,ug/ml) DO Meter
Low Level (ppb,ug/ml) DO Meter
DO-32a Dimensions
DO-32a Dimensions

Main Unit

DO-32A Low Density DO Meter
for continuous thermal water systems.


Measuring Method Membrane type polarographic method
Display LCD
Measuring Range Dissolve oxygen
0 to 19.99ug/L(ppb), 0 to 199.9ug/L (ppb)
0 to 1.999mg/l (ppm), 0 to 19.99mg/L (ppm)
Temperature 0-45 C

Range Change Over Automatic/manual
Repeatability Dissolved Oxygen
+/- 0.1ug/l (at 0-19.99ug/l range)
+/- 0.3ug/l (at 0-199.9ug/l range)
+/- 0.03mg/l (at 0-1.999mg/l range)
+/- 0.003mg/l (at 0-19.99mg/l range)
Temperature +/-0.1C (accuracy +/-0.5C)
Temp Comp Range 0-45 C (Automatic temp compensation)
Output Dissolve Oxygen:
Measuring Range:
0 to 1V (0 to FS at each range)
0-450mVDC (0-45C)
100mV (at 0 to 19.99ug/l range)
200mV (at 0 to 199.9ug/l range)
300mV (at 0 to 1.999mug/l range)
400mV (at 0 to 19.99mg/l range)
Ambient Conditions Temperature: 0-45C, Humidity: 0-85%RH
Power source AC/DC AC line by adapter or 9VDC Alkaline battrery R6, AA or UM-2: 6 pcs.
Main Unit Size Approx. 250(w) x 160(H) x 95(d) mm
Main Unit Weight Approx. 2.1 Kgs

Dissolved Oxygen Electrodes

Type OE-5843-02 OE-5844-02
Application General Use Type -Low level dissolved oxygen electrode.(2m lead) Atomic Power Plant Process type electrode (2m lead)
Wetted Material FEP, PP, Epoxy resin, Silicon rubber FEP, PP, Epoxy resin, 316SUS, silicon rubber
housing Material PP 316SUS
Flow Rate of Sample 0.05 to 2L/min. (with flow cell)
Remarks High response: about 15 min from saturation to 5ug/L
Low residual current; less than 1ug/l
Long Life span of electrolyte: about 6 months when using continuously with sample less than 10mg/L

Standard Accessories

Flow Cell , DO-F-30 1 pce.
Low level DO Electrode 1 pce.
Dry Battery 6 pcs, alkaline
AC adapter 1pce
Output Cable (DO-350L) 1 pce.
Carrying Case (DO-C-350) 1 pce.
Shoulder Belt (DO-SB) 1 pce.
Remarks Inlet/Outlet of flow cell: 1/4" tube (6.35mm)

Accessories and Consumables for the DO-32A

OE-584302 General Use Type -Low level dissolved oxygen electrode.(2m lead)
OE-584402 Atomic Power Plant Process type electrode (2m lead)
R-6B Electrolyte.
T-25 DO Membranes (10/box)
YD-12 AC adapter.
DO-F-30 Flow Cell
DO-C-350 Carrying Case