During preventative maintenance of the device at northgate technologies, inc; it was noted in service evaluation the insulated wire from the high voltage transformer was disconnected from the high voltage printed circuit board (hv pcb).There was no evidence of arcing within the unit (metal housing) or that the unit was fired with the disconnected "broken" wire from the high voltage board.It is currently unknown if this damage was present in the field or occurred in transit.This report is being filed as a malfunction because the disconnection of the wire from the transformer to the hv pcb constitutes an increased risk of potential shock if the disconnected wire were to come into contact with the metal housing.The device was investigated under capa 22060.There are no burn marks found inside the cover which supports that the unit has not been discharged after the high voltage wire broke from the high voltage board.It is unclear at this time how the hv wire became disconnected from the hv pcb.A possible root cause could be that this occurred during a cover removal and reinstallation process of the unit at the user facility and the insulated wire from the high voltage transformer to the pcb was either accidentally pulled or yanked.Warnings have been provided in the operator's manual that "the unit should not be opened except by a qualified service person.Tampering by unqualified persons can damage the unit and void the warranty".The operators manual indicates the dielectric and leakage testing has to be performed annually on devices.This device would fail that testing with the wire disconnected.The device history record for #(b)(4) from (b)(6) 2016 (mo (b)(4)) was reviewed and the device passed all testing.Nothing out of the ordinary was noted.The device has not been returned to nti for repair / evaluation previously.There have been no other complaints reported to nti for this device.A corrective action of applying a tie wrap to secure the high voltage transformer cable that prevents it from coming loose from the power resistor was implemented under ecn-4493, on 30th march, 2020.Nor-doc-dra-0025 risk analysis was reviewed.Risk id 7.3.5 (a) refers to accidental mechanical damage with a potential hazard of patient or user injury by a damaged device.The potential hazard is delay in surgical procedure due to the machine not operating.The risk level post mitigation is an n which makes this an acceptable risk.There is an indication in the manual stating "be sure to inspect the autolith® touch unit and any accessories for proper operation before each use.If the unit is found to be defective or damaged, it should be returned to the manufacturer or qualified service personnel for inspection and repair." a clinical evaluation was performed per nor-doc-cer-0002 which proved the benefits of lithotripsy outweigh the risks.Nor-doc-dra-0025 risk analysis, risk id 7.1.1(a) addresses, "electricity - possible shock to patient and/or user due to electric shock" with the possible hazard identified as "break down of insulation on internal generator wires could cause electric shock".The mitigation is that the device was evaluated and passed iec 60601-1 safety testing.The severity is identified as a 5 (potential death) with a likelihood of severity of a 1 (incredible).The risk of death, or serious injury is considered less than remote.A clinical evaluation was performed per nor-doc-cer-0002 which proved the benefits of lithotripsy outweigh the risks.If further information were to become available, a follow-up report would be submitted.
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