Support for unit conversion is available in OpenGround Data Collector.
This is important for regions where mixed units are used, such as in Canada where it is common to collect drilling data in imperial units (feet) but report it in metric.
Data Collector Profiles can be set up to use Primary or Secondary Units by default. There is also the option to override the default Units for individual headers. Values are converted on the device and synced back to the cloud database in the Primary Units.
Table of Contents
Setting Default Data Entry Units
The Default Units for a Data Collector Profile can be set in Admin Portal.
Select your Configuration Pack and Profile and click on Edit Profile. There is a drop-down for the Default Data Entry Unit. This will be set to 'Primary' by default but can be set to use 'Secondary' Units.
(If you have an existing profile that you would like to set up to use different units, note you can use Copy Profile to make a new version.)
Reviewing Default Units
If you go to Manage Steps>Configure Step, you will see a read-only field for the Default Data Entry Unit. This field tells you the Unit used for that header depending on the Default Units set for the Profile. The following behavior applies:
- If you set the Default Units to 'Primary', the Primary Unit will be shown.
- If you set the Default Units to 'Secondary' and a Secondary Unit is defined for that header, the Secondary Unit will be shown.
- If you set the Default Units to 'Secondary' and a Secondary Unit is not defined for that header, the Primary Unit will be shown.
- If a Primary Unit is not defined, no Unit will be shown.
- Default Units are only shown for headers with a 'Decimal' Data Type.
Both Primary and Secondary Units can be edited in OpenGround Professional at System>Configuration Packs>Manage Model.
Overriding Default Units
In Manage Steps>Configure Steps, you will also see an editable field for the Data Entry Unit. This can be used to override the Default Data Entry Unit.
For example, to enter values in 'ksf' instead of 'kPa', set 'ksf' as the Data Entry Unit.
Data Entry Units will be restricted to the same Unit Group as the Primary and Secondary Units, and can only be set for headers with a 'Decimal' Data Type.
Data Entry Units can not be set for calculated headers (i.e. where a 'Calculated Value' expression is entered). Calculated headers will use the Default Unit.
How it works in Data Collector
On Forms and in Grids in the Data Collector app, the user will see fields labelled with the Units specified in Admin Portal.
Data is converted and stored in the background on the device in the Primary Unit but is always shown on the device with the Units set in Admin Portal. Data is synced to the cloud database in the Primary Units, such as can be seen in OpenGround Professional or OpenGround Portal.
Expressions
Data Collector profiles can be set up to use calculation expressions, such as for 'Hide If' conditions, 'Default Values', 'Calculated Values', 'Validation Expressions', and 'Action Default Values'.
If these expressions are 'unit-dependent', it is important that they are written with respect to the Primary Units. All values are stored and calculated on the device using Primary Units. Calculated values are then shown back to the user in the Data Entry Units.
In the example below, the Primary Units for Length are millimeters, but the Data Entry Units are inches. Depth Base is calculated by adding the Length (in meters) to Depth Top. The expression should be written with respect to the Primary Units, such that the Length in millimeters is converted to meters by dividing by 1000 – even though the Length will be entered in inches.
For example, in Data Collector, the Sample below has been entered at a Depth Top of 10 feet with a Length of 24 inches. Depth Base is calculated in the background using the metric Primary Units, and the converted value of 12 feet is shown back to the user.
It is important to be mindful of this behavior for certain types of data, such as for SPT's. For example, SPT's are commonly performed using "6-inch" intervals in imperial units, but with "150-mm" intervals in metric units. However, 6 inches = 152.4 mm so this is not an exact conversion. If you have unit-dependent calculations, such as for determining and reporting refusal, these "imprecise" conventions could result in inaccurate results. You might need to adjust calculations accordingly, or try to avoid unit conversion where possible for such scenarios.