Wis. Stat. § 409.609: Secured party’s right to take possession after default.

(1) Possession; rendering equipment unusable; disposition on debtor’s premises. After default, a secured party:

(a) May take possession of the collateral; and

(b) Without removal, may render equipment unusable and dispose of collateral on a debtor’s premises under s. 409.610.

(2) Judicial and nonjudicial process. A secured party may proceed under sub. (1):

(a) Pursuant to judicial process; or

(b) Without judicial process, if it proceeds without breach of the peace.

(3) Assembly of collateral. If so agreed, and in any event after default, a secured party may require the debtor to assemble the collateral and make it available to the secured party at a place to be designated by the secured party which is reasonably convenient to both parties.