7.—(1) This paragraph applies where the attachment of earnings order has been made—N.I.
(a)by the Office, or
(b)by a court otherwise than to secure payments under a maintenance order.
(2) The employer shall on any pay-day—
(a)if the attachable earnings exceed the protected earnings, deduct from the attachable earnings the amount of the excess or the normal deduction, whichever is the less;
(b)make no deduction if the attachable earnings are equal to, or less than, the protected earnings.