The facility library contains all facility types, their respective properties and meanings. 

The systems of the facility library and the inheritance of types works best if it's efficiently build and managed.

That's why we'll be talking about some important aspects in form of a best practice that will help you with the management of the facility library.

Rules for the creation of types, meanings and properties

As general as possible and as specific as necessary

Designing all facility types and their elements as general as possible means that they can fit as many scopes as possible. This mans that a type and its properties and meanings should, for example, be build to apply to various facilities. Such a structure enables the usage of a facility type for lots of facilities and an easy inheritance of properties to subordinate facility types.

However, the facility types and their elements should also be modeled as specific as possible. They should be used in an universal way but still be specific enough to optimally match the requirements of their scope.

Example: The facility type "Room" can be used for a facility that should represent an office, because it is designed to match all rooms without any special requirements. However, a facility for a cooling chamber might come with certain specifications that require a more specialized type.

Control if a new type is necessary!

Some facilities are so specific that they need their own type, because they require settings that are not covered by other types. A new type should only be created if that's the case!

Example: A new facility for a coffee machine needs properties like "Manufacture" and "Warranty until" that are covered by the type "Equipment". So this type could easily be used for a coffee machine. It would only be necessary to create a new type if a special property is needed, e.g. "Type of coffee beans". 

Use the inheritance wisely!

Properties are passed on from higher-ranking to subordinate facilities. Like this, general properties can be reused at specialized types. That's why they should be used as high as possible. 

Example: The facility type "Electricity meter" requires the property "Calibrated until" This property is also used by the higher-ranking type "Meter" and all of its subordinate facility types. However, it would not make sense to add this property to "Equipment", because not all of its sub-types would use it. "Calibrated until" should therefore be used by the highest possible type "Meter" so it can reasonably be passed down to its sub-types.

Use meanings to separate data!

If it's necessary to separately aggregate data, you'll also need separate meanings.

Example: In most cases, it does make sense to separately evaluate load profiles for gas and electricity. The meaning "Load profile" could of course be used for both, but then it would make it impossible to separate the data, especially at higher-ranked facilities. If there is a need for separate aggregation, like in this case, separate meanings should be used. 

Tips for properties

Group up properties reasonably!

A reasonable grouping of properties tidies up the property page of a facility and helps the user to add new properties and assign them correctly.

Example: The facility type "Equipment" enables you to add a lot of information about your appliances as properties. General information like the manufacturer ir the inventory number are grouped up, just like all technical data and the dimensions of the device.