Set of Measurement Units

After creating your units of measurement, you can create a set of measurement units, which will define the quantity relationship between the units that comprise this set. Units of measurement that have been pre-defined in the system can be also added to such sets.
You can create sets of measurement units that are generally applicable to several/many items or you can create a set specifically for a particular item. For example, a set of measurement units created for an item Sand will include such units of measurement as a ton (t) and a cubic meter (m3). The conversion ratio in this set is 1 cubic metre = 1.5 tons and this quantity relationship is defined specifically for the item Sand. The quantity relationship between the same units may be different for other items. For example, the conversion rate between a cubic meter and a ton is 1 cubic meter = 1.6 tons in a set created for an item Broken stone.
In a created set of measurement units, you have to select a base unit which will be used in accounting and inventory transactions. For example, if you select a cubic meter as a base unit for the item Sand, all transactions will measure the quantities of sand in cubic meters even if you indicate the quantities in tons while creating invoices.  For instance, you indicate in an invoice that you sell 15 tons of sand for 45 EUR (3 EUR for 1 ton). This data is saved and displayed in the invoice. However, transactions triggered by the invoice display the quantities in cubic meters, instead of 15 tons of sand for 45 EUR we have 10 cubic meters of sand for 45 EUR.
Sets of measurement units can be assigned to existing items or used when creating new ones. Then, all units an assigned set contains are available for use when you work with an item in sales, purchase or inventory documents.
 The Set of measurement units directory cannot be accessed from the Main menu. You can go to it only from the Item directory, from the page for defining new items. To do that

1. Go to the General area of the Item form page, and then turn on the Use several units of measurement option.

2. In the field Set of measurement units, click Create new.

You are taken to a page for defining a new set of measurement units.

3. Enter details of the set of measurement units, and then click Save and close.

As a result, you are taken to a listing page of the Set of measurement units directory. From here you can access all created sets of measurement units.

More information
Measurement Unit
Create a New Set of Measurement Units
Set of Measurement Units: General Area
Set of Measurement Units: Measurement Units Section