WT-HR
Water Height
Data
Logger
The WT-HR is a Three Channel, High Resolution (12 bit), Water
Height and Dual Temperature Datalogger fitted with a water height probe. Water height
probes are available for:
| ¼ meter |
250mm |
WT-HR 250 |
| ½ meter |
500mm |
WT-HR 500 |
| 1 meter |
1000mm |
WT-HR 1000 |
| 1½ meter |
1500mm |
WT-HR 1500 |
| 2 meter |
2000mm |
WT-HR 2000 |
A temperature sensor is located at the bottom of
the water probe and another is mounted in the logger so both water and air temperatures
can be logged.
Photos and Application
notes
| Specification: |
|
Water
Height: |
|
|
Sensor Type |
| Capacitive |
| 304 Stainless Steel Outer |
| 316 Stainless Steel available for
special orders |
|
|
|
Working Temperature |
0º C to +70º C |
|
|
Accuracy |
± 1% Full Scale |
|
|
Resolution |
± 1mm |
|
|
Temperature Coefficient |
| Not Compensated |
± 0.65mm/meter/º C Water Temp
± 0.5mm/º C Air Temp |
| Compensated |
± 0.2mm/º C |
|
|
|
Note: |
Water
Height readings can be temperature compensated using Water temperature readings. |
|
|
|
|
|
Internal
Temperature: |
|
|
Sensor Type |
Thermister |
|
|
Linear accuracy over range |
± 0.3º C (0º C to 70º C) |
|
|
Repeatability |
± 0.1º C |
|
|
Long term stability |
± 0.1º C |
|
|
|
|
|
External
Temperature: |
|
|
Sensor Type |
Thermister |
|
|
Sensor Position |
Bottom of Water Height Probe |
|
|
Working Temperature |
0º C to +70º C |
|
|
Linear accuracy over range |
± 0.3º C |
|
|
Repeatability |
± 0.1º C |
|
|
Long term stability |
± 0.1º C |
|
|
|
|
|
Logger: |
|
|
Working Temperature |
-30º C to +70º C |
|
|
Storage Temperature |
-30º C to +70º C |
|
|
Sampling Rate |
| 1 second minimum |
| 10 hours maxium |
| in 1 second intervals |
|
|
|
Storage capacity |
| 64,000 8 bit samples |
| 32,000 12bit samples |
|
|
|
Alarms |
| Two independent Alarms |
| Triggered on any combination of six user configurable Alarm
Conditions |
| One alarm can be configured to dial a PocketPager |
| Alarms can be visually checked using the Omnilog Software |
|
|
|
Start modes |
| Start immediately |
| Start on date/time. |
|
|
|
Stop modes |
| Stop when memory is full |
| Stop on date/time |
| Loop around (continues logging) |
|
|
|
Logging Modes |
| Each channel can be set to log any combination of: |
- Point readings
- Average reading
- Maximum reading
- Minimum reading
|
|
|
|
Battery |
| Factory Replaceable |
| One ½ AA 3.6V lithium cell |
| Five year life. |
| The data is retained in the case of battery failure. |
| Battery Status Monitor in OmniLog Software |
|
|
|
Download Time |
35 seconds for Full Logger |
|
|
Case material |
304 Stainless tube
316 Stainless Steel available for
special orders |
|
|
Screw on end cap |
Plated brass
316 Stainless Steel available for
special orders |
|
|
Size |
| Logger |
Length |
Diameter |
Weight |
| WT-HR 250 |
515mm |
20mm |
395gm |
| WT-HR 500 |
820mm |
20mm |
588gm |
| WT-HR 1000 |
1320mm |
20mm |
975gm |
| WT-HR 1500 |
1820mm |
20mm |
1363gm |
| WT-HR 2000 |
2320mm |
20mm |
1750gm |
|
Compensating for Temperature Coefficients
The WT-HR water height probe has a small
negative temperature coefficient with respect to water temperature. If the probe is
sitting in 1 meter of water and experiences a water temperature increase of 1° C, the
logger will report a water height decrease of 0.65mm. If you log water temperature, the
Omnilog software can compensate the logged water height value to correct the small
negative temperature coefficient of the probe.
In addition to this, the logger has a small positive
temperature coefficient with respect to air temperature. If a probe is sitting at 0mm of
water and experiences an air temperature increase of 1° C, the logger will report a water
height increase of 0.5mm. If you log air temperature, the Omnilog software can compensate
the logged water height value to correct the small positive temperature coefficient of the
logger.
Logging both water and air temperature, as well as water height, decreases the number of
samples you can store in the logger. If the air and water temperature are going to be
reasonably constant, (eg. down a well) you can log water height only. You can also log
water height only if your required accuracy is greater than 10mm. The water temperature
has a larger coefficient than the air temperature, so if you can only afford to log one
temperature it is recommended that you log water temperature.
If you attempt to start the logger without selecting both water and logger temperatures a
warning message will appear.
