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Introduction |
| A 3 year old Breville waffle machine part no 1923362 type VST072 tripped the rcd/rccb (residual current circuit breaker) switch after about five minutes from turning on. It may not have been used for at least 3months. | | Tear-down showed no obvious distress other than normal 'wear and tear'. The resistance between live and earth pins with a cheap multimeter exhibited rising values typically 200 kohm to 2Mohm over about 20 sec, as did the individual heating elements when isolated. The elements also had a capacitance of 4 to 6 uF which may have caused problems for my cheap multimeter. | | | After heating the extracted heating elements in an oven for an hour at 150C, the insulation resistance had significantly increased ie no resistance below 2Mohm was detected and it no longer tripped the RDC switch. |
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