If you already have existing equipment of an equipment type, disable the equipment type rather than delete it.

An equipment type can be disabled at any time by clearing the EnableCreation checkbox for the equipment type in the EquipmentTypeSettings configuration table. This prevents further instances of this equipment type from being created in ThingWorx Apps. When creating new equipment in ThingWorx Apps, only equipment types with the EnableCreation checkbox selected are displayed in the Type drop-down list. Existing equipment of that equipment type is unaffected.

When an equipment type is deleted from the EquipmentTypeSettings configuration table, the association between the EquipmentType, ThingTemplate, ResourceProvider, and ConfigurationMenu is lost. As a result, although existing equipment of the disabled equipment type is not deleted, it no longer functions as expected.