Type A rcd . EICR coding ? etc

As far as test gear goes Mike, I have a whole room full, and 3 various digital oscilloscopes, with 8 channels between them and enough bandwidth to see your local TV transmitter. I am not at the scope stage yet, and I will probably video the results when I have found what there is to know. No point in doing it now as otherwise I just get hours of video which is hard to edit properly.


The comment about additional protection from Andy is a point, but how does a person contact anything inside the boiler, an Earthed metal box? If the boiler leaks it does trip so far, but that is just normal Earth leakage protection which is not personal protection from a class 1 appliance, and time is much less important. I am expecting that leakage of more than an amp or so should pop the appliance's internal fusing, as it is clearly an internal fault. Please don't mention the heating man working live, that is his problem, not the consumer and clearly he should be using the correct PPE, and of course be fully trained to do this. I am still very much at a loss as to how this kind of fault under discussion occurs, the LV directive makes it pretty much impossible unless there are multiple problems. Think clearance distances, insulation, etc.


My tests are rather different as I said above, I use the tester on the mains supply after the RCD, 3 wire as normal, and a DC 4.5A load and a resistor from the DC+ to Earth. Nothing unusual from the case where one would expect the RCD to operate. I will look at the current waveforms later, and check what happens with leakages from + to Earth greater than about 45mA when I get some lower value resistors. The test bench supply is direct from a TNC-S supply without an RCD.


An interesting point about this internal pump, have you a circuit diagram of how it is connected? Any external wiring should either be mains voltage and Earth, or a SELV supply either isolated to class 2 or one side Earthed.

As far as test gear goes Mike, I have a whole room full, and 3 various digital oscilloscopes, with 8 channels between them and enough bandwidth to see your local TV transmitter. I am not at the scope stage yet, and I will probably video the results when I have found what there is to know. No point in doing it now as otherwise I just get hours of video which is hard to edit properly.


The comment about additional protection from Andy is a point, but how does a person contact anything inside the boiler, an Earthed metal box? If the boiler leaks it does trip so far, but that is just normal Earth leakage protection which is not personal protection from a class 1 appliance, and time is much less important. I am expecting that leakage of more than an amp or so should pop the appliance's internal fusing, as it is clearly an internal fault. Please don't mention the heating man working live, that is his problem, not the consumer and clearly he should be using the correct PPE, and of course be fully trained to do this. I am still very much at a loss as to how this kind of fault under discussion occurs, the LV directive makes it pretty much impossible unless there are multiple problems. Think clearance distances, insulation, etc.


My tests are rather different as I said above, I use the tester on the mains supply after the RCD, 3 wire as normal, and a DC 4.5A load and a resistor from the DC+ to Earth. Nothing unusual from the case where one would expect the RCD to operate. I will look at the current waveforms later, and check what happens with leakages from + to Earth greater than about 45mA when I get some lower value resistors. The test bench supply is direct from a TNC-S supply without an RCD.


An interesting point about this internal pump, have you a circuit diagram of how it is connected? Any external wiring should either be mains voltage and Earth, or a SELV supply either isolated to class 2 or one side Earthed.