12.1.1 Bill Of Materials Overview
A Bill of Materials, BOM, can be described as a list of items required to produce a finished assembly or sub-assembly. For example, a bill of materials for a circuit board might consist of resistors, diodes, and the raw circuit board itself. The finished board could in turn be a sub-assembly for a finished product such as the radio BOM shown below.
A Bill of Materials could be called a recipe, formula, cut list, etc. pc/MRP can accept BOMs infinite levels deep. When entering a BOM you must enter the lowest levels first as pc/MRP is always checking if the part or sub-assembly exists. In the above example, you would first enter the diode, resistor, and raw board into the part master as parts. Then you would enter the finished circuit board bill of materials listing all of the parts that go into a finished circuit board. You could then enter the radio bill of materials.
pc/MRP uses the BOM files to provide PIC Lists, Where-used Reports, Purchasing Consolidation Reports, Assembly Costs, and to correctly issue and track inventory.
BOMs are not limited to manufacturers, for example, restaurants can correctly track inventory by entering their recipes into pc/MRP's BOM file.
A single level printout of an example BOM is shown below:
An exploded printout includes sub BOM parts and their respective quantities. pc/MRP uses a technique called indenting to help illustrate how the sub assemblies fit together with other sub assemblies to create the final assembly. The same example BOM in an exploded print out is illustrated below:
12.1.2 New BOM (Create A New BOM)
By selecting Modules, BOM, and New you can enter a Bill of Materials into the Bill of Materials Database File.
First, you will be asked to enter the new Bill of Materials Number and a BOM Description. Your description should begin with Assy, FG, or WIP to distinguish it as an assembly and not a part. You should choose your wording of the description carefully as good, logical descriptions can improve the usefulness of your alphanumeric part list printouts.
pc/MRP will check if that BOM number already exists in inventory and the BOM data base files. If pc/MRP finds that number in inventory or the BOM data base file it will display an "Already Exists" error message. If this message appears select another BOM number or edit the existing BOM if that is more applicable.
12.1.3 BOM Component Tab Screen
After selecting an acceptable BOM name and entering a BOM description the main BOM creation and editing screen will appear. From this screen you can begin the process of entering parts into your BOM.
An example of this screen is provided below.
The parts and sub-assemblies that make up the BOM will be displayed in a grid as shown above. The grid will contain the following columns. The Item Number column contains the BOM item number for that part in the BOM being displayed. The Type column represents the type of component it is, P = component part, A = Assembly, L = Labor. The Part Number column contains the part/sub-assembly number that goes into the BOM being displayed. The Description and Quantity columns are self-explanatory. You can sort the displayed list by clicking on the column heading (Item, Type, etc.) you wish to sort on.
When you click on a part number, that part's BOM Item Number, BOM quantity, Type, Description, Manufacturer, Model Number, Issue Unit, Average Cost, Standard Cost, Last PO cost, and Alternate Part Numbers are displayed in their respective text boxes.
Alternate Part Numbers can either be manually entered or automatically updated through using Option 54 in the Settings and Utilities Module.
The Staging Bin field can be used to enter a staging area or bin number for parts and sub-assemblies being issued to WIP.†† In addition the single and exploded Pick Lists (picbom.frx) can be sorted by staging bin.
To add a line item to a BOM, click on the Add Item button. See section 12.1.6.
To edit/delete a line item in a BOM, select the part number and click on the Edit Item button. If you mark a line item for deletion, the line item will be displayed in red
To drop and edit/view a sub-assembly of the displayed BOM, press the Move to Sub-Assy button.
To move back up to the parent assembly of the displayed sub-assembly, press the Move to Parent Assy button.
To save your changes and continue working on the displayed BOM, press the Save button.
To discard your changes, press the Revert button
To save your change and return to pc/MRPís main menu, press the Finished button.
12.1.4 BOM Reference Designator Tab Screen
Clicking on the Reference Designator Tab will display the reference designator page shown below.
Reference Designators for each part or assembly can also be entered. The Reference Designator field can have an infinite length and can be printed out on an Uncosted Single Level Bills of Materials Report. It is used by circuit board manufacturers to help assemblers know where to place components on the circuit boards is C1, C2, C3, etc. It can be used by regular manufacturers to list special instructions for assembly, such as, cut 13" long
12.1.5 BOM Miscellaneous Tab Screen
Clicking on the Miscellaneous Tab will display the miscellaneous page shown below.
Pressing the BOM Used button will display where the selected BOM you are modifying is used in other BOMs.
Pressing the Part Used button will display where the selected part or assembly is used in other BOMs.
Pressing the BOM Image button will display a picture of the assembly, if the there is a picture of the assembly in inventory. Pressing the Part Image button will display will display a picture of the assembly, if the there is a picture of the assembly in inventory. For further information about images see Chapter 4.1.1.
This page will display the Average, Standard, and Last PO Costs of the BOM you are modifying. Pressing the Assembly Costs Recalculate button will force pc/MRP to recalculate and display the costs.
Pressing the BOM Comments button will allow you to enter comments applicable to the entire BOM. The comments field can contain up to 20 lines of routing or assembly instructions for that BOM.
12.1.6 Entering New Parts/Assemblies Into A BOM
Clicking on the Add Item button will display the screen shown below
The Item Number will automatically increment as additional parts or assemblies are added. The part number entered may be for either a part or another BOM. To select the part or assembly you wish to add to the BOM, click on the ellipsis button to the right of the part number button. This will bring up an inventory scroll window, allowing you to look up and select a part or assembly by part number, description, or model number.
The Part Type, Description, Manufacturer, Model Number, Unit, and Costs are brought over automatically from inventory.
The Alternate Part Numbers can be entered manually or automatically brought over from inventory depending on how you have set the alternate part numbers to be entered with the Settings button. See section 12.1.7.
The Create New Part button will allow you to enter a new part number into inventory on the fly without having to go to the Inventory Module to enter the new part number
After entering the desired part or assembly enter the desired quantity of this part or assembly to be added to the BOM. This can be done by entering a number in the Quantity field.
If you desired to enter an assembly that does not exist you will have to exit this BOM, build the lower level assembly first, than add it to this BOM. All BOMs should be built from their lowest level up.
The BOM screens will accept but not record changes to the Part Data. Use the Inventory Edit Program, Edit BOM Number, or Edit BOM Description program to change these fields.
12.1.7 BOM Settings Button
Clicking on the Settings button when adding or editing a BOM part number will display the screen shown below
The Component Lookup drop down list box allows the user to set the method the BOM module looks up part numbers. The options are:
Checking the Transfer Alternate Part Numbers check box will set pc/MRP to automatically transfer alternate part numbers from the part number in inventory into the BOM record. If the alternate part numbers are BOM specific, do not check this check box.
12.1.8 Edit/Delete a BOM Component (View)
This option allows users to scroll, edit, delete, undelete or run queries against BOM records.
Selecting an Indexed Search allows users to search on indexed fields.† This allows pc/MRP to find the information much faster.† To perform an Indexed Search select the:
∑ Indexed Search tab
∑ Desired Sort Order, BOM Number, Part Number, BOM Description
∑ Enter the applicable data in the Begin Scrolling At: field
∑ Select the desired Action, View or Edit
∑ Press Search
pc/MRP will automatically scroll to the desired record or the nearest match.† Select the correct record by scrolling and press Ok to proceed to the edit screen for that record.
Selecting to run a Queried Search allows users to build, run, save, and load queries for the BOM table.† For further details see chapter 15.14.
Please review the Enter New BOM section of this chapter as the view and edit BOM screens function the same as the enter new BOM screens.
12.1.9 Delete an Entire BOM
Allows you to mark a BOM for deletion. You must remember to run Remove Marked BOM Records to delete the BOM from the DBF files.
12.1.10 Duplicate A BOM
Allows you to duplicate a BOM.
12.1.11 Change A BOM Number
Allows you to change a bill of materials number without having to edit every record that contains that bill of material number. pc/MRP also changes the number in inventory.
12.1.12 Change A BOM Description
Allows you to change a bill of materials description without having to edit every record that contains that bill of material description. pc/MRP also changes the description in inventory.
Allows you to print or display BOMs, PIC Lists and Where Used Reports.
See section 15.4.1 to create custom reports.
Selecting a Report Type
To select the report type that you want, place your cursor on the list arrow on the top drop down list box and click. You are then given the following list to choose from:
†† Uncosted Single-Level BOM
†††††††† Costed Single-Level BOM
†††††††† Uncosted Exploded BOM
†††††††† Costed Exploded BOM
†††††††† All BOMs
†††††††† Where Used Reports
†††††††† Single-Level Pick List
†††††††† Exploded Pick List
The list will look like this:
Select the BOM Number
Next, you would enter in the BOM number that you want printed or displayed where the BOM Number box is.
Select the Number of Assemblies
At the Number of Assemblies box, either type in the number you want or use the spinner button to scroll up and down through the list.
Select Cost Type
Note: This option will only be available when you select a Costed BOM. Three radio buttons allow you to select which type of costing method is preferable to you. The Average cost will average the total cost. The Standard cost will give you the standard cost. The Last PO cost will give you the cost of the last purchase order.
Select Sort By
Sorting by Part Number will use the part numbers to order the BOMs. Sorting by Root Number will use the root numbers to order the BOMs. Sorting by Item Number will use the item numbers to order the BOMs.
Select Send Report to:
At this option, you can chose to see a display of the report, print it out on either wide or narrow carriage, or send it to a file.
Select Report Type
The Standard report will print/display the way you selected it to be. If you have custom created your reports, then you can print/display them using the Custom report option.
Whenever you run an exploded costed BOM Report, pc/MRP will automatically recalculate the average or standard cost of that BOM and place the new figure in inventory.
The Where Used Report will provide a printout for all parts or for a specified part number. The printout will provide a list of every assembly that uses that part number. It will also note parts that are not used in any assembly. The latter feature is designed to help reduce inventories and inventory write-offs.† If the Single Part option is select users can include all levels of the assemblies where the part is used.
PIC Lists are used by stock room personnel to print out the parts required for an assembly or sub-assembly.
An exploded PIC list includes all of parts including parts from sub-assemblies in one consolidated list.
The Reference Designator Fields print out on the wide carriage PIC List, wide carriage Uncosted BOM, and narrow carriage uncosted single level BOM reports.
12.1.14 Audit The BOM File
This option will check your BOM data base file. As a safety precaution make a back up copy of the partmast.dbf and bom.dbf files before running this option. Select, "Compile a list of errors", when prompted. Once you have looked at the error list you can run the report again and select, "Step-through each BOM record with the option to remove it." This program will scan the bom.dbf file and look for the following errors:
12.1.15 Index (The BOM File)
Re-indexes the Bill of Materials Index File. pc/MRP automatically updates its index files under normal operation. However, if you ever get a "record out of range" error message or cannot find a BOM record, re-indexing inventory or the BOM module may fix this.
12.1.16 Remove Marked BOMs
Removes all BOM records marked for deletion from the disk. The records will no longer be recoverable.
12.1.17 Phantom Bills of Materials
If you plan to purchase a sub-assembly from a vendor and not build the subassembly in house, it would be called a phantom BOM. This can be accomplished in pc/MRP by editing the BOM in the Inventory Module and changing the PART/ASSY/LABR field from A to a P. The MRP module would then create action items to buy the sub-assembly from a vendor rather than buying the components and issuing a make for the sub-assembly. However, you would still be able to print this phantom BOM in the BOM module.††
With pc/MRP version 7.51 and higher, option 68 in the Configuration, Settings and Utilities module allows users to step down through phantom BOMs (sub-assemblies marked as P in the inventory module) while editing or printing out a costed or uncosted exploded BOM.† Option 68 also allows users to set the default print settings to: never print out phantom BOM subassemblies, always print, or ask.