The Australian Services Union says a planned week-long walkout by 150 NCR engineers would quickly impact cash machines operated by three of the Big Four banks - CBA, Westpac, ANZ - and some credit unions.

The industial action - set to begin on Monday - has been called following a breakdown in negotiations over annual salary rises.

NCR area general manager, Noel Pettitt, told the Syndey Morning Herald that the company has contingencies in place to deal with any problems that might arise.

"We've re-jigged our workforce and arranged things such that we'll certainly deal with priority calls in the first instance but continue to deal with the balance of calls," he told the paper.