UPDATE 1-Nortel subsidiary files for creditor protection

* NNCI files for creditor protection in Delaware

* NNCI expected to continue normal day-to-day ops

TORONTO, July 15 (Reuters) - Nortel Networks CALA Inc (NNCI), a U.S. subsidiary of bankrupt Canadian telecom equipment maker Nortel (NRTLQ.PK), filed for bankruptcy on Wednesday.

NNCI is an operating entity serving the Latin America region with headquarters in Sunrise, Florida, the company said.

The voluntary petition under Chapter 11 of the U.S. bankruptcy code, is limited to NNCI and does not include any of NNCI's subsidiaries or any affiliates in Caribbean and Latin American countries, the company said. It was filed in U.S. Bankruptcy Court in Delaware.

A spokesman for Nortel declined to comment on whether other subsidiaries of the company would follow in NNCI's footsteps.

Nortel said NNCI sought Chapter 11 protection to preserve and administer its assets and business in a manner consistent with the Nortel's larger restructuring efforts.

NNCI's normal day-to-day operations are expected to continue without interruption.

The unit has estimated assets of between $100 million and $500 million, with estimated liabilities in the range of $500 million and $1 billion, according to court documents.

The case is In re: Nortel Networks CALA Inc, U.S. Bankruptcy Court, District of Delaware, No. 09-12515-KG. (Reporting by Tom Hals in Delaware and Euan Rocha in Toronto; Editing by Derek Caney)