This setting is unchecked by default, and functions as an extra check for tracking variances against the budget. The setting will track the difference between the item's purchase order amount and budget and forces the user to enter a variance code for that difference.
When the purchase order item is sent to Job Cost, a message dialog appears (this message appears when changes are made in the Issue Purchase Orders screen, such as when a supplier is changed, cost is changed, etc.). The Select a Variance Category dialog appears and requires the user to enter a Variance JC Category code. As a result, POs cannot be issued until the Variance JC Category is assigned. This setting will also take effect during the Refresh Costs process in the Issue Purchase Orders screen.
When an item is copied that has had budgets already issued, the total amount of the item will be tracked as a variance. When an item is added using item takeoff (budgets don't have to be already issued), the total amount will also be tracked as a variance. Additionally, if the user attempts to issue a purchase order for an item whose variance category has not been assigned, theInvalid JC Variance Category error will appear, and will not allow the user to continue with the PO issuance.
When this setting is enabled, the Detail pane for the item will indicate the item has a variance tracked and display its variance category, variance amount, and original budget amount.
Access the Integration menu > Accounting > Accounting Integration Settings.
Or, select the Accounting Integration Settings 
icon from the toolbar.
Verify the accounting company currently selected in the Accounting Companies grid is the correct accounting company for which this setting will be defined. If necessary, click on a different accounting company.
Click the Accounting Configuration tab.
To enable the tracking of variance categories on reissued items, select the Track Variance Categories on differences between Budget and Commitment checkbox. As a result, the setting above it, Track Variance Categories on Reissued Items, will also become enabled.
Click the Save 
button at the top of the screen to save any changes.
Track Variance Categories on Reissued Items