M-Log can graph data from the HH2 hand-held portable data recorder, manufactured by Delta-T Devices.
The HH2 can read and record data from the Profile Probe (PR1), ThetaProbe (ML1 & ML2), and Equitensiometer (EQ1 & EQ2).
The PR1 has 4 (or 6) capacitance soil moisture sensors on a rod which can either be taken from site-to-site to record readings, or it can be left at a single site with a logger. The HH2 is only used if the PR1 is used in portable mode - if the PR1 is left at a site with data recorded by a fixed logger M-Log needs to be configured for that logger.
Data is downloaded from the HH2 and then processed to distribute it to a separate data file for each site.
You will now be able to graph the data by clicking on each sensor.
Installation and configuration is described below - for further details see the M-Log manual.
Install M-Log from CD (
The sample database of loggers and sensors will be listed - click on a sensor to plot the sample data.
needs to be licenced to allow changes you make to be saved (It will, in practice, run for 30 days before a licence is essential).
You can create a new database for the PR1 data...
Alternatively you can add new loggers to an existing M-Log database.
New loggers and sensors will be created after readings are uploaded and processed.
Set Data Set Up 502 Set
Read Save data ? Set
The data should now be in a file called:
ddMMyy.UPL - it can be checked using
If you use
DeviceID new loggers and sensors will be automatically created, with the new logger number the same as the
DeviceID entered into the HH2 at each site. The lookup file will not be used.
Processto distribute the uploaded data to a separate file for each site - it can be checked using
If a logger does not exist with the same number as the
DeviceID number, you will be prompted to create a new logger (site).
A new logger (or site) can be created by copying either...
If more than one tube is installed at a site, and each tube is given the same site identifier, the data can be averaged.
Averaging several tubes at the same site - if you are taking continous readings at a single site each set of readings must be more than 'minimum time between scans' apart, otherwise all the readings will be averaged.
If multiple theta probes are being used at each site the HH2 is connected to each sensor in turn, and a separate DeviceID number entered. A lookup file must be used, with the column (or depth number) of each sensor entered in the lookup file. If continuous readings are being taken at the same site each set of readinmgs must be more than 'minimum time between scans' apart.
After uploading and processing the HH2 memory is cleared with...
<Set> Data <Set><Up> Erase <Set>
Erase ? <Set>
The HH2 is configured for use with a PR1 (access tube) with...
The HH2 is prepared for uploading with...
Useto show the current battery and memory status of the HH2.
The HH2 converts the output of the profile probe from volts to soil moisture. The Delta-T Profile Probe manual provides a polynomial and a linear equation, for both organic and mineral soils.
The HH2 appears to default to the polynomial equation. However a trial in Australia showed that the linear equation gave better agreement with measured applied water at high moisture contents.
Both M-Log and Probe for Windows can have calibration equations entered, allowing the use of the linear equations and to change the equations at any time in the future. If you are going to use this feature the HH2 should be set to ouput in mV.
Profile Probe User Manual, page 18
Equations to be entered into M-Log and Probe for Windows to convert from mV -> % (0-100)
Organic: Slope = 0.129 Intercept = -0.11
Mineral: Slope = 0.140 Intercept = -0.08
Download this document in Word DOC format.