HOBO® Dissolved Oxygen Logger (U26-001) Manual
15603-E MAN-U26x
The HOBO Dissolved Oxygen logger is a standalone logger that uses RDO® Basic Technology
to measure dissolved oxygen (DO). The logger has an optical sensor that provides 0.2 mg/L
accuracy. The logger also features an easily replaceable sensor cap and an integrated
temperature sensor. Using HOBOware® software for logger setup and a HOBO Waterproof
Shuttle for quick data offload, this logger is easy to deploy in both freshwater and saltwater
environments making it an ideal tool for environmental impact studies as well as ecological
and oceanographic research. Using the data offloaded from the logger, the HOBOware
Dissolved Oxygen Assistant can calculate percent saturation and salinity-adjusted DO
concentration as well as correct for measurement drift from fouling (additional meter or
logger measurements required).
Specifications
Dissolved Oxygen
Sensor Type
Optical (dynamic luminescence quenching)
Measurement Range
0 to 30 mg/L
Calibrated Range
0 to 20 mg/L; 0 to 35°C (32 to 95°F)
Accuracy
0.2 mg/L up to 8 mg/L; 0.5 mg/L from 8 to 20 mg/L
Resolution
0.02 mg/L
Response Time
To 90% in less than 2 minutes
DO Sensor Cap Life
6 months (cap expires 7 months after initialization)
Temperature
Temperature Measurement/
Operating Range
-5 to 40°C (23 to 104°F), non-freezing
Temperature Accuracy
0.2°C (0.36°F)
Temperature Resolution
0.02°C (0.04°F)
Response Time
To 90% in less than 30 minutes
Logger
Memory
21,700 sets of DO and temperature measurements (64 KB total
memory); logging stops when memory fills
Logging Rate
1 minute to 18 hours
Time Accuracy
±1 minute per month at 0 to 50°C (32 to 122°F) (see Plot A)
Battery
3.6 V lithium battery; factory replaceable
Battery Life
3 years (at 5 minute logging)
Download Type
Optical
Depth Rating
100 m (328 ft)
Wetted Materials
Black Delrin®, PVC, EPDM o-rings, silicon bronze screws; rated
for saltwater use
Size
39.6 mm diameter x 266.7 mm length (1.56 x 10.5 inches);
mounting hole 7.88 mm (0.31 inches)
Weight
464 g (16.37 oz)
The CE Marking identifies this product as complying with all
relevant directives in the European Union (EU).
Plot A: Time Accuracy
HOBO Dissolved
Oxygen Logger
U26-001
Included Items:
•
Dissolved Oxygen
Sensor Cap
•
Protective Guard
•
Calibration Boot and
Sponge
Required Items:
•
Coupler (COUPLER-2-C)
with USB Optic Base
Station (BASE-U-4)
or
HOBO Waterproof Shuttle
(U-DTW-1)
•
HOBOware Pro 3.3.1 or
later
Accessories:
•
Replacement Dissolved
Oxygen Sensor Cap
(U26-RDOB-1)
•
Anti-Fouling Guard
(U26-GUARD-2)
•
Sodium Sulfite
(U26-CAL-SOL)
You May Also Need:
•
For saltwater, salinity or
conductivity measurements
are required; HOBO
Conductivity/Salinity
Logger (U24-002-C)
recommended
•
For percent saturation,
barometric pressure is
required; HOBO Water
Level Logger (U20-001-0x
or U20L-0x) recommended
HOBO Dissolved Oxygen Logger with
Included Calibration Boot and
Sponge (Shown Wet in Photo)
