Se essa capacidade estiver incorporada na impressora (que parece ser), siga o manual no site da Brother:
Start your web browser.
Type "http://machine's IP address" in your browser's address bar (where "machine's IP address" is the machine's IP address). For example: http://192.168.1.2
Click the Administrator tab.
Click the User Restriction Function menu in the left navigation bar.
Select Secure Function Lock.
Click Submit.
Click the Restricted Functions menu in the left navigation bar.
In the User List / Restricted Functions field, type a group name or user name (alphanumeric, up to 15 digits).
In the Print and the other columns, select a check box to allow or clear a check box to restrict the function listed.
To configure the maximum page count, select the On check box in the Page
Limits column, and then type the maximum number in the Max. Pages field.
Click Submit.
Click the User List menu in the left navigation bar.
In the User List field, type the user name.
In the PIN Number field, type a four-digit password.
Select User List / Restricted Functions from the drop-down list for each user.
Click Submit.