Selection of the preferred time base

The time base with which the loaded signal values are to be displayed later is set in the HD query dialog in the Time Selection area via the Preferred time base drop-down list.

Depending on the requirements for the time resolution of the queried data, select a small time base (high resolution) or a larger time base (lower resolution).

The values offered in the list are standard values and are only approximate. The actual time base with which the data can be loaded is determined by the store in the ibaHD-Server. Only the original time base (highest resolution) and the automatically determined time bases of the various aggregation levels are available.

The following cases may occur when selecting the preferred time base:

The preferred time base is the same as an existing time base in the HD store:

The data is loaded with this time base.
The preferred time base is smaller than any time base in the HD store:

The data is loaded with the smallest available time base.
The preferred time base is between a smaller and a larger time base in the HD store:

The decision as to which existing time base is loaded is made by ibaHD-Server using the following formula:
- The larger time base is loaded when
- Otherwise, the smaller time base is loaded.

Depending on how large the set time range is, the choice of time base has a considerable effect on the amount of data.

In the HD query dialog, you can only select the time range for the query, not for specific signals. During an HD query, ibaAnalyzer always loads all signals contained in the HD store in question for the set time range.

If the set time base is very small and the time range is very large, the amount of data to be loaded may exceed the memory capacity. This means that further processing or analysis of the data is only possible to a limited extent or not at all. ibaHD-Server therefore calculates the amount of data to be expected depending on the set time range and marks the limits in color for the time base values in the drop-down list. If you select Auto as the preferred time base, the optimum time base is selected automatically.

In addition, a tooltip indicates possible difficulties if you select the relevant time base anyway.

Color	Meaning
Red	The set time range and this time base require more memory than ibaAnalyzer can provide. If you select this time base without reducing the time range and execute the query, an error message appears. The query cannot be executed. Set a different time range or a different time base in the HD query dialog.
Orange	With the set time range and this time base, ibaAnalyzer can provide sufficient memory. However, only limited analysis functions are possible or only a few signals can be displayed. If you select this time base without reducing the time range and execute the query, a message appears. You can execute or cancel the query and select a different time range.
Green	With the set time range and this time base, extensive analyses are also possible without any problems. If you close the HD query dialog with <Execute query>, the query is executed.

Color

Meaning

Red

The set time range and this time base require more memory than ibaAnalyzer can provide. If you select this time base without reducing the time range and execute the query, an error message appears. The query cannot be executed.

Set a different time range or a different time base in the HD query dialog.

Orange

With the set time range and this time base, ibaAnalyzer can provide sufficient memory. However, only limited analysis functions are possible or only a few signals can be displayed. If you select this time base without reducing the time range and execute the query, a message appears.

You can execute or cancel the query and select a different time range.

Green

With the set time range and this time base, extensive analyses are also possible without any problems. If you close the HD query dialog with <Execute query>, the query is executed.