UPDATE 2-Pan Pacific's copper plant halted since Jan 7 after fire

* Asia spot price may rise if suspension prolonged -buyer

* PPC says has ample inventories of anode

* Nov refined copper inventories 80 pct of month's output (Adds Pan Pacific comment)

TOKYO, Jan 10 (Reuters) - Pan Pacific Copper, Japan's biggest copper smelter, said on Tuesday it suspended operations at its 200,000 tonnes per year Saganoseki smelter on Jan. 7 after a fire damaged an electric power substation on the site.

The company is checking when it can resume operations at the plant in Oita, southeast Japan, and whether its other smelter and refining plants in Japan can make up for lost production, a spokesman said.

The Saganoseki plant produces anode, an intermediate state of refined copper, for refining at its Hitachi plant.

"We can't say for now when we can start operations at the Saganoseki plant. It all depends on when we can secure parts for damaged electronics machines," said a company spokesman.

"But we have ample inventories of anode for the time being," he said.

Asia's premiums for spot refined copper could rise if there is a prolonged suspension at Pan Pacific, an exporter to China, Taiwan and South Korea, prompting its term buyers to turn to the spot market.

A copper buyer for Pan Pacific Copper's metal in China said no information had been received from the Japanese supplier on whether the fire would delay term refined metal shipments.

"From our experience, they are likely to buy copper from the spot market for term deliveries if that is the case," the buyer said.

Pan Pacific signed contracts last October to supply a total of 110,000 tonnes of refined copper to customers in China, Taiwan and South Korea at a premium of around $100 above the London Metal Exchange cash price for shipments in 2012.

Premiums for bonded copper in Shanghai traded at about $120-$140 a tonne over cash LME copper prices last week.

An industry official said he did not expect a large impact on the domestic market from the shutdown, given a relatively high level of inventories of refined copper.

Domestic inventories of refined copper at smelters stood at 93,639 tonnes at the end of November, against November output of 112,305 tonnes, according to the Japan Mining Industry Association.

Sluggish demand for refined copper had helped push up domestic inventories from the 68,000 tonnes level in 2010.

Pan Pacific, part of JX Holdings Inc, has a refining plant in Hitachi in east Japan and a smelter and refining plant in Okayama in the south of the country. The company has a total output capacity of 710,000 tonnes a year.

Pan Pacific plans to produce 272,400 tonnes of refined copper in the six months to March 31. (Reporting by Yuko Inoue; Editing by Joseph Radford and Michael Watson)