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What are ‘UNITS OF MEASUREMENT’

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If you measure output, or define ‘speed’ you want to do this in a certain ‘unit’ i.e. meters, liters etc.  Maximum speed, amount of output can all be expressed in different ‘units’ of measurement.

The maximum speed is expressed in output per unit of time. The unit of time is equal to the unit of time in which the availability is expressed (default is minutes; this is defined in the Machines master-table).

Define the unit of measurement for the output e.g. pieces, kg, liters, square meters etc. Do not deviate from what is already being measured as output within the present registration of data.

Example: a bottling company may be using ‘liters’ and ‘bottles’ as units of output: the department that fills the bottles counts in bottles on their machines, while the mixing department counts in liters. In addition, take into account that for the quality rate, we need to know not only how many products the machine manufactures, but also how many products are good and not good. The unit of good product must therefore correspond to the unit of scrap and rework products.

Most common units are predefined. You may add units or modify the descriptions as desired in master table ‘units of measurement’. This section will assist you with entering or changing the ‘units of measurement’

What does it do?

The ‘units of measurement’ are not just ‘labels’. In many situations different units of measurement will be used alongside; the product contains 33 centi-liters product, the machine fills 500 liter per minute and the line-management looks at Hectoliters being processed. Here we define what units we want to use and how they compare.

Categories and units

There are 7 categories of units. Those categories cannot be changed.

Each Category can contain multiple units than can represent values in that category. You may enter units from different systems in one category, in metric and imperial. The software will then be able to convert from one unit to the other.

Per category you will find predefined units of the most commonly used measures. You can add or change them when needed.

[Unit] per [Time]

The Unit of measurement has two sides:

[Unit] per [Time]:  The unit in which we count and the timeframe we count:

There are two ways to look at ‘counting’

[6 items per minute]  is the same as:

[10 seconds per item]

OEE Coach registers always [Unit] per [Time].

In the Unit of Measure master-table, all the potential Units are (pre-)defined.

In the Machines master-table, per machine is being defined what unit in what timeframe is being registered.  

So to define a unit of measurement for a machine we have to specify both [unit] and [time]

The time is a predefined enumeration: You may choose from:

  • Seconds
  • Minutes (Default)
  • Hours

One reference measure

All units in one category will have one reference measure; the unit carrying the value ‘1’. The others in the same category can be deduced by the factor it has been given.

Example:

How to Add/Modify Units of Measurement

  • Select [MASTER]
  • select [UNITS]
  • After choosing a category (select in the left-pane) you may want to add a new unit to that category.
  • After pressing [+] you will be able to give this new unit a name.
  • Calculate the ratio of this unit in relation to the reference unit (the one having a ratio of 1).

So how does the new unit relates to 1 reference unit?

If [meter] = 1 Millimeter relates to meter as 0,001; a mm is 0,001 m

How to change the reference unit

In the above example, all variants in the category “Length” are being referenced to the unit ‘Meter’ (read this as “1 centimeter equals 0,01 meter”,“1 meter equals 1 meter”

If you would like to reference from meter to ‘centimeters’, simply change the table starting centimeters as “1”:

Centimeters as reference unit:

How to use Metric and imperial units mixed

Your OEE Coach provides a default table of lengths units including imperial units, all referenced to meter.

How to use Yards as reference unit, not meters…

Default in the length category, meters is the reference unit. If you like to change this into Yards, just put Yards as [1] and recalculate and change all other units to yards.

What happens when I change the Unit of Measure?

The Unit of Measure master table is used to fill your OEE database. In this OEE database, historical data is being stored.

Data that is being changed in the ‘Unit of Measure’ master table will not affect already stored shift data in the OEE database.

So if you change [Liter] into [Litre] on July 1, 2015, you will find [Liter] in the OEE data stored until that date, and after this date you will find [Litre]. Same applies to the ratio being used.