Object Types

As mentioned above, the GAM_OBJECTTYPE table represents the specific model of an object from a specific manufacturer. Therefore, an object that is a Helios 100A dewar is of object type Helios 100A, of object class dewar, of function storage.

There is a many to one relationship with total participation between the GAM_OBJECTTYPE and GAM_OBJECTCLASS, each class has one or more types, and each type must belong to a class.

Between the GAM_OBJECTTYPE and GAM_OBJECT tables there is a one to many relationship with total participation, each object type has one or more objects.

Between the GAM_OBJECTTYPE and GAM_DISPLAYFORMAT tables there are 5 optional many-to-one relationships. A display format can be applied to multiple types, and each can have up to 5 display formats.

Calibrations

A calibration refers to a translation between a measured value and the actual value, defined using a function. This function is captured in the table with the OT_CALIB_X, OT_CALIB_Y and OT_CALIB_NPOINTS attributes.

The optional OT_CALIB_X and OT_CALIB_Y attributes represent arrays of x and y coordinates, respectively. Each pair of values at the same index represent a break-point on the graph of the piecewise linear function between the level and the volume. The OT_CALIB_NPOINTS attribute defines how many elements are in each array.

The x axis of the function represents the measured value, and the y axis represents the actual values. These are generic and can be anything depending on the situation.

One such situations is for objects that store liquids, where we want to measure their level. But these objects are not always perfect cylinders, and as a result the function from the level to the current volume of liquid is not a linear one. For example, if a vessel is more narrow in its middle portion, a 1 cm increase in the level will result in a smaller increase in liquid volume compared to if the 1 cm increase occurred in the wider base of the object.

Another reason you want to have a calibration for helium vessels is that they do not only store liquid Helium, they also store some gas Helium because due to evaporation. Depending on what you want to measure, you need to take this into account.

Object type table

Attribute name	Attribute meaning	Data type	Mandatory	Notes
OT_ID	ID of type	24-bit Integer	Yes	It is the primary key.
OT_OBJECTCLASS_ID	ID of the class of this type	24-bit Integer	Yes	It is a foreign key to the GAM_OBJECTCLASS table.
OT_NAME	Name of this type	String, up to 50 bytes in size	Yes
OT_OUTOFOPERATION	If the object is out of operation, 0 by default.	0 or 1, 1 for out of operation, should not tolerate null	No	You never should clear objects, object types or object classes (or anything else) from the database as old measurements will reference to it.
OT_VOLUME	Volume of objects of this type	Number with a precision of 10 digits, and a scale of 4	No
OT_SUBSTANCE	Substance stored or used by objects of this type	String, up to 20 bytes in size	No
OT_COMMENT	Comment regarding this object type	String, up to 1000 bytes in size	No
OT_PRODUCER	The manufacturer of this type of device	String, up to 200 bytes in size	No
OT_MODEL	The model of this type of device	String, up to 200 bytes in size	No
OT_INTERNAL_TCOMP	For gas counters, which have internal temperature compensation	Integer from 0 to 9	No	For GasCounter
OT_TEMP_NORM	Temp normal, know which temp this is compensating, for gas counters	Number with a precision of 10 digits, and a scale of 4	No	GasCounter
OT_INTERNAL_PCOMP	For gas counters, which have internal pressure compensation	Integer from 0 to 9	No	For GasCounter
OT_PRESS_NORM	Pressure normal, know which pressure this is compensating, for gas counters	Number with a precision of 10 digits, and a scale of 4	No	For GasCounter
OT_STEP	Incremental step meant for gas counters, gas counters operate in steps	Number with a precision of 6 digits, and a scale of 4	No	For GasCounter
OT_CALIB_NPOINTS	The number of calibration points on the defining the calibration function	24-bit Integer	No
OT_CALIB_X	A string representing the array of coordinates on the x axis of each calibration point	String, up to 1000 bytes in size	No
OT_CALIB_Y	A string representing the array of coordinates on the y axis of each calibration point	String, up to 1000 bytes in size	No
OT_CALIB_NAME	Name you give to your calibration	String, up to 200 bytes in size	No
OT_DF_ID_1	ID of the first display format of this type.	24-bit Integer	No	It is a foreign key to the GAM_DISPLAYFORMAT table.
OT_DF_ID_2	ID of the second display format of this type.	24-bit Integer	No	It is a foreign key to the GAM_DISPLAYFORMAT table.
OT_DF_ID_3	ID of the third display format of this type.	24-bit Integer	No	It is a foreign key to the GAM_DISPLAYFORMAT table.
OT_DF_ID_4	ID of the fourth display format of this type.	24-bit Integer	No	It is a foreign key to the GAM_DISPLAYFORMAT table.
OT_DF_ID_5	ID of the fifth display format of this type.	24-bit Integer	No	It is a foreign key to the GAM_DISPLAYFORMAT table.