Tumble drier tripping RCD

Often two thermal cut outs above element , one trips out and then resets, the other is triggered at higher rate and would need replacing if blown , yours may have the former tripping.
 
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Often two thermal cut outs above element , one trips out and then resets, the other is triggered at higher rate and would need replacing if blown , yours may have the former tripping.
It's the RCD that has tripped.
The internal RFI filter is one of the few components in a domestic appliance that can cause an RCD to trip, and then blow itself to pieces without serious consequences to the appliance.
Is there any consequence to using the machine with the exploded filter while waiting for the new £15 part to arrive? Here's a clearer view of the explosion.
You should be able to use the machine while waiting. The filter is there to provide interference suppression for sensitive devices - i.e. there is the possibility for interference to your WiFi etc, while the machine is in use, without it.

Edit: ..that is, as long as the only issue is with the filter.
 
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There is always a risk, with a damaged component in circuit, but the risk is slight. Your RCD will help considerably, to reduce the risk.
Good point, I had assumed that as nutjob had removed the filter, he would leave it out and bridge the wires.
A rather poor assumption really!
 
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How to test EMI filter.

I'm afraid the video has quite a simplistic explanation of the filter.

The typical circuit of an RFI/EMI filter is something like this...

1731194880298.jpeg

The L in & L out, and the N in & N out terminals are both connected by inductors  L - they are very unlikely to fail open circuit.
If either of the capacitors on the load side pop, they are both connected to earth, hence the RCD trip.
He measures the resistance across the L and N terminals to test the filter. This won't necessarily give you an idea of the health of the capacitors - it will only let you know that the inductors and resistor R are healthy, and it would tell you if a capacitor has shorted out - something unlikely to happen, as class X and class Y capacitors are designed to fail open circuit.

But as earlier, theoretically (given the simplicity of the filter circuit), the capacitors can pop in the filter, with little consequence for the behaviour of the appliance.
 
Partial test is still better than no test, though. So, why would earthing fault occur at the moment of explosion, but not after the event?
 
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Partial test is still better than no test, though. So, why would earthing fault occur at the moment of explosion, but not after the even?

The capacitor has blown itself out completely clear, so there is no earth leakage to trip the RCD. That type of capacitor, is designed to suffer a minor fault, and be able to self-seal/ recover, but in your case it looks like a complete failure.
 
So, why would earthing fault occur at the moment of explosion,
An RCD can trip due to an imbalance in current between L and N - the difference in current, leaking to earth.
With the two series capacitors across L and N, operating correctly, the system is in balance.
If one of those caps were to blow, short, or both go at near the same time; there would be a brief moment where the currents through L and N weren't balanced; there would be a current path to earth through one cap and not the other, the RCD would trip.
After the trip event had occurred, as Harry says, the cap would have blown itself clear. The system is again in balance, and no more trips.
 

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