Language:


Introduction to the Machine Hours register

The Machine Hours register allows you to record the hours when your Machines operate. This information will have an impact on the calculation of the Should Start date in Production Orders, and on the scheduling of those Production Orders in the Resource Planner.

You will often create Production Orders from Sales Orders with Planned Delivery Dates. The Due Date in a Production Order created from a Sales Order will be the Planned Delivery Date in that Sales Order. The Should Start date in the Production Order is the date when work should begin, in order for it to be completed by the Due Date . T he Should Start date will be calculated from the Due Date, taking into account the Fixed Assembly Days, the Days, Hours, Minutes and Seconds to Produce and the Time to Setup recorded in the Recipe, and the Buffer Days and the Round Odd Hours To One Day option in the Production Settings setting. The Days, Hours, Minutes and Seconds to Produce together are the time required to produce a single unit, while the Fixed Assembly Days and the Time to Setup are independent of the quantity being produced. For example: :

Planned Delivery Date of Sales Order (qty 2) January 25
Days to Produce for the first unit (from Recipe) 2
Days to Produce for the second unit (from Recipe) 2
Fixed Assembly Days (from Recipe) 1
Buffer Days (from Production Settings) 5
Should Start DateJanuary 15
A Production Order created by the 'Create Planned Records' and 'Create Planned Records from Orders' functions from such a Sales Order will therefore have a Should Start Date of January 15, in order to meet the Due Date (i.e. the Planned Delivery Date) of January 25. This Production Order will appear in the Resource Planner as shown below:

The Days to Produce and the Fixed Assembly Days in the Recipe and the Buffer Days in the Production Settings setting are assumed to be 24-hour days. The calculation of the Should Start date therefore assumes that work will be carried out constantly. If this assumption is not correct, you should use the Machine Hours register to specify the working hours of your Machines. For example, the working day might not be 24 hours as so far assumed, but eight hours.

You should enter a separate record in the Machine Hours register for each Machine Group.

Enter a Machine Group in the Group field using ?Paste Special?, and choose the colour to be used in the Resource Planner to signify Time when Machines belonging to the Group can not be used (i.e. times when the Machines are idle). This should be a different colour to that in the Recipes that you will use the Machines to produce.

In the remaining fields, specify the time each day when you can begin using the Machines belonging to the Machine Group, and how long you can use them. The hours field will accept figures with one decimal place. In the example illustrated, work will begin at 8 am and end at 4 pm (i.e. each working day is eight hours).

Enter zero in an hours field if the Machines in the Group will not be used at all on a particular day, as shown for Saturday and Sunday in the illustration. If the Machines are to be used for the entire day (i.e. for 24 hours), leave the relevant hours field blank.

These Machine Hours will change the calculation of the Should Start date in Production Orders. The 'Create Planned Records' and 'Create Planned Records from Orders' functions will calculate this date as follows:

  1. They will first check the Production Item Alternative register to find the Machine that can produce the Item in the Sales Order.

  2. They will then check the Machine Hours register to find the working hours for the Machine Group to which the Machine in step 1 belongs.

  3. They will calculate the date when work should start in order to meet the Planned Delivery Date, as described earlier on this page.

  4. The date when work should start will be adjusted, to take the Machine Hours into account.
This sequence demonstrates that if you are using the Machine Hours register, you must also use the Production Item Alternative register to specify default Machines for each Item.

The Machine Hours illustrated above will mean that work on the example Sales Order can no longer begin on January 15 to meet the January 25 deadline, because we have now specified that the Machine cannot be used constantly. These changes mean that work must begin on December 31. So, when we use the 'Create Planned Records' or 'Create Planned Records from Orders' function to create a Production Order to satisfy the example Sales Order, the Should Start date in that Production Order will now be December 31. This Production Order will appear in the Resource Planner as shown below:

The working hours are shown in red (as specified in the Recipe), and the time when the Machine is not working is shown in grey (as specified in the Machine Hours register).

You can also create Production Orders from Production Plans using the 'Create Productions' Maintenance function in the MRP module. In these Production Orders, the Should Start and Due Dates will be copied from the Start and Needed Dates respectively in the relevant row in the Production Plan. In this Production Plan row, the Start Date will have been calculated from the Needed Date using the formula described above (i.e. using the Fixed Assembly Days, the Days, Hours, Minutes and Seconds to Produce and the Time to Setup recorded in the Recipe, the Buffer Days and the Round Odd Hours To One Day option in the Production Settings setting, and the information in the Machine Hours register for the relevant Machine Group). So, the Should Start date in a Production Order will be calculated using the same formula, irrespective of whether that Production Order was created from a Sales Order or a Production Plan.

---

See also:

Go back to: