IBM Corp has an embarrassing problem with mainframe disk drives imported from Europe and adapted to work on American power, the Technology News Ltd newsletter Infoperspectives International reports. On August 27, IBM service engineers received a missive headed DASD ALERT…SAFETY, which opens It has come to our attention that recently there has been an influx of 3390-type devices being imported to the US, and goes on to note that as most, if not all were originally built for 50-cycle power they need to be adapted to run on 60-cycle power – a rework that IBM does not offer. It advised that disks that have been adapted for American use by independent service companies should no longer be considered certified by the independent testing lab Underwriters Laboratories – that IBM uses to verify the safety of its drives, and warned that technicians working on the drives could be exposed to unsafe conditions as well as some additional liabilities – but failed to tell them how to identify the disks in question. On September 7, IBM told customer engineers to defer accepting newly-converted European 3390s for maintenance but to continue maintaining those already on contract; it also told them how to identify disks from Mainz. All the disks in question would have been inspected by IBM before it took them onto maintenance contract, and it appears that the trigger for the alert was an incident where IBM inspected some converted 3390s owned by a disk dealer in August and issued a standard maintenance acceptance qualification letter. But the disks failed shortly after they were powered up because the fans in the air blowers were pushing air the wrong way and the head-disk assemblies overheated, crashed and burned. The emergency thermal cut-out in the blower assemblies didn’t work because it detects air flow, not head-disk assembly temperature, and the air was moving, but going the wrong way. IBM at first blamed the technicians that did the conversion, saying they had wired the blowers backwards when installing them – but it turns out that the blowers are complete units that cannot be plugged in backwards. IBM has said it will now re-inspect installed 3390s for safety purposes – it reckons that there are about 200 in the US, third parties say 500 – but these are not in single strings but scattered, and it says that it will tighten procedures for certifying others.
