Moeller Electric has discovered a potentially serious safety problem that could affect hundreds of its circuit-breakers supplied between 1987 and 1993. The company is warning that premature ageing of an electronic component used in its IZM breakers, could prevent the breaker from tripping correctly. This could result in a loss of power or a fire breaking out, and could cause personal injuries, depending where the breaker is installed.

Moeller has been contacting customers who bought the IZM breakers and is offering them free inspections and replacements, if necessary. But the company does not know where all of the breakers are installed, and is appealing the users to check their control panels and distribution boards.

One way of identifying the affected breakers is to examine the colour of the setting buttons on the trip units. If these are black or white, the breaker may be affected by the problem. Digital circuit breakers and those with blue setting buttons are not affected.

Moeller will send its UK customers a checklist is they send an email to izm.check@moeller.co.uk. Alternatively you can phone the company on (44) 01296 393322.

"This is a serious safety problem," Moeller says in a message to its customers, "and you are therefore kindly requested to attend to this problem soon, and inform us without delay" .