The need to manage a large volume of entities is intertwined with the human effort to classify and encode the elements of each entity. Aristotle’s great contribution to the study of the natural world consists in the first systematic recording of the animal and plant kingdom, giving the first “code” names to plant categories and animal species.
Since ancient times, all developed cultures have been based on their social organization and recorded in organized archives of all their citizens. So today, the identity of every citizen is linked to the code of his identity card. Of course, for the needs of a modern society, there are often parallel codings that serve different needs (eg VAT, AMKA).
But also inside a factory there are many codes used for the same equipment: Machine Code, Account Code, Serial Manufacturer Number etc. Although my personal view is that in many cases all codings can be unified in this article we will confine ourselves to what is the most appropriate method to encode a technical part of its equipment for the needs of its maintenance.

As a result, this article will develop:

1. Clarification of equipment structure
2. Coding functionality rules
3. Ways of marking machines

1. Clarification of equipment structure

Before any coding attempt is very important to clarify the structure of the equipment we want to encode. In the figure below we see a custom structure based on ISO 14224 so that we can understand the classification more clearly.

The basic level in each structure is the level of equipment (machine). What we will define as a machine depends on what we want to watch. B.C:
• Anything that costs and is accounted for?
• Anything that is damaged or should be prevented?
• Anything that supports the basic operation of the plant / company?

For example, in many cases their engines are considered as independent equipment (separate code) and sometimes as a part of a main machine.
How many levels will be used above or below the level of the machine depends on the size of the company and / or the units and the degree of analysis we want to monitor the maintenance activity. An important role also plays the type of information we want to manage:

• At what level do we want to monitor maintenance costs?
• How far do we want to analyze the fault categories?
• Which machines are maintained simultaneously at long stops?

• How are machines / instruments / components to be encoded on a single network (eg Air, steam, electricity, water etc) and serve different machines?
• Should the correlation between primary and secondary equipment be captured?
• Only the machines and / or the places where they are to be encoded (Very useful for cases where we have removable equipment)?
• How should the back-up machines in the warehouse be encoded?

3. Ways of marking machines

1. It is recommended that no more information be found on the machine code and its description. In many cases, the code may be sufficient.
2. The size of the labels attached to the machines may be proportional to the size of the machine and the distance from which we can access the machine. This, of course, does not mean we have to have more than 3 different sizes. (For example, in a large tank or a machine that we can not get close to, we will use the large label sizes)
3. The strength of the label material used must be commensurate with the nature of the manufacturing process (eg ambient liquid or hot or heavy objects). Typically metallic signs that can be scanned are commonly used. (Due to the fact that the process of re-issuance or addition of labels is often required, it is advisable to ensure the appropriate flexibility). There are also very good plastic labels or high-strength labels that can be printed on a classic laser printer.
4. The stabilization process on the equipment is also important. Mechanical restraints are more painful / time-consuming in their application, while high-strength adhesives are commonly used.
5. Finally, where you wish to exist