IEC 60601-1 - Medical Electrical Equipment Safety 13.2: Single fault conditions

What does 13.2 require?

While each single fault condition in 13.2.2 through 13.2.13 is applied, the 8.1 normal conditions are applied too, combined in the worst way: electrical faults per 8.1; transformer overheating per 15.5; thermostats and temperature limiting devices short-circuited or interrupted, whichever is worse, with the overload tests of 13.2.13 and 15.4.2; liquid escaping in single fault condition creates no unacceptable risk, sealed rechargeable batteries excepted, with test conditions from the risk management process; equipment stays single fault safe on failure of cooling, simulated by locking fans in turn, covering top openings or placing against walls, blocking filters and interrupting coolant, judged by the 11.1 methods against the 13.1.2 limits; moving parts are locked where accessible or applied parts can jam, where the equipment may run unattended (including automatic or remote control) or where locked-rotor torque is below full-load torque, one part at a time unless one fault locks several motors; motor capacitors in auxiliary windings are short- and open-circuited in turn with the rotor locked and capacitor voltage measured open-circuit against its rating, the short-circuit test omitted for IEC 60252-1 capacitors in attended-use equipment; motor faults run from cold at rated or upper-range voltage for 30 s for hand-held and hand-held-on or hand-loaded equipment, 5 minutes for other attended-use equipment, the maximum timer period where a timer ends operation, or to thermal stability otherwise, with winding temperatures at the end or at the instant a protective device operates against Table 26 by insulation class; oxygen-rich component failures per 11.2.2 and mechanical part failures per clause 9 and 15.3; and after the overload tests the equipment, cooled to room temperature, remains safe, with thermoplastic insulation on which a means of protection depends ball-pressure tested at 25 degrees above its measured temperature. Heating equipment is tested without adequate heat discharge at 90 or 110 percent of rated voltage whichever is worse until a non-self-resetting cut-out operates or thermal stability is reached (rated operating time for non-continuous equipment), heating parts additionally at 110 percent with each temperature-limiting control other than a thermal cut-out disabled in turn at the rated duty cycle to stability, with element rupture repeated on a second sample; motor equipment is tested by the locked-rotor, capacitor and running tests, low-voltage motors where measurement is impractical being wrapped in cheesecloth that must not ignite, combined heating and motor equipment with both operating for the worst case, motors run unattended or under automatic or remote control by one device tested for running overload by stepping up the load to stability until protection operates or the temperature stops rising against Table 27, three-phase motors run with one phase disconnected, and non-continuous-rated equipment other than hand-held, hand-held-on, hand-loaded or dual-timer equipment run at normal load and rated voltage until the peak temperature rises less than 5 degrees in an hour or protection operates, against the 13.2.10 limits.