LONDON, March 17 (Reuters) - The London Metal Exchange (LME) said on Thursday some nickel orders could not be entered during the 0730-0800 GMT pre-open period on its LMEselect electronic trading system.
Pre-open is a process where traders enter bids and offers ahead of trading, which for nickel currently starts at 0800 GMT.
"As such, in order to ensure fair time priority of orders, the pre-open period was repeated between 0815-0845 GMT and nickel trading on LMEselect commenced at 0845 GMT," the exchange said.
Traders said the problem was that they could not enter offers at the 8% limit-down level of $41,945 a tonne and that the system would only accept a level 5.25% below Wednesday's close.
The LME widen the nickel trading limit to 8%, effective Thursday, from 5% the day before.
"We were able to enter orders at 8% limit down by 0750 GMT and then it accidentally opened at 0756 GMT before suspending again," one metals trader said.
Telephone and ring trading were operating normally, the LME said.
The LME suspended nickel trading on Tuesday last week after prices spiked by more than 50% to over $100,000 a tonne and it resumed trading on Wednesday with an adjusted starting price of under $48,000 and a limited trading range of 5% either side. (Reporting by Pratima Desai; Editing by David Clarke)