Electric shock from tumble dryer? A live wire touching the body of the tumble dryer, a damaged cord, or bad earth are all reasons why this might be occurring. This post will try to explain why you might be getting a shock from a tumble dryer and what you can do about it from the perspective of an electrician.
Why Get An Electric Shock From A Tumble Dryer
An electric shock from tumble dryer occurs when contact between a high voltage and earth occurs. This essentially creates a ‘short circuit’ allowing current to flow through someone’s body via their skin and organs. This results in an unpleasant ‘shock’ sensation which is dangerous and potentially deadly.
In this case, the high voltage might be located on the body of the tumble dryer (touched by someone’s finger or hand) and the earth connection would be someone’s bare feet touching the ground. The electrical current travels between these two locations.
Due to the danger of shock, all wiring must be done according to specific rules and regulations in each country. For example, most circuits need to be on residual current devices (RCDs) which shut off power to a circuit when an electric shock occurs (or is about to occur).
Typically, RCDs shut off power when 30 milliamps of leakage current within 300 milliseconds has been reached. There are more sensitive RCDs available for places like hospitals and schools.
For RCDs to work there needs to be a good earthing system in place. This means that all appliances with metal surfaces need to be earthed. It also means that all general domestic power outlets need to be earthed. Only double insulated appliances (class 2 appliances) need not be earthed.
Other rules around protecting against electric shock include special rules around wiring lights, power points and appliances in wet areas and following manufacturers instructions when using appliances.
With this in mind, let’s look at why someone might be getting a shock from a tumble dryer.
Electric Shock From Tumble Dryer – Reason #1
Live Wire Touching Body Of Tumble Dryer
A tumble dryer typically has several conductive (meaning electricity can travel) parts. This can include the outside body and inside the ‘cage’ of the tumble dryer. If a live wire or fault in the heater or motor inside the tumble dryer comes in contact with the body of the dryer then that will result in hazardous voltages appearing which can cause an electric shock.
The buildup of debris or moisture inside the tumble dryer can also cause an electrical fault.
In our experience, even rodents (attracted by the warmth generated by dryers) can get into small openings of older tumble dryers and build nests, chew wires and wreak havoc on the electrical workings inside. These chewed wires can definitely cause an electric shock.
Movement and vibration from the motor inside the dryer can cause wires to come loose in cheaper models. Loose wires present an electric shock hazard.
Electric Shock From Toaster – Reason #2
Damaged Electrical Cord
A damaged electrical cord caused by rodent chewing or being squashed can expose live electrical wires. If these are touching the conductive body of the tumble dryer, someone will definitely get a shock.
Electric Shock From Toaster – Reason #3
Tumble Dryer Frame And Body Not Earthed
As mentioned earlier, if the body of the dryer isn’t connected to the earthing system either at the dryer (via a green & yellow cable bolted to the body) or at the power outlet (earth missing or transposed at power outlet), then it is possible for hazardous voltages to appear on the tumble dryer which will result in electric shock.
Without a good earth, then the RCD on the circuit will not operate in time (or at all) resulting in a bad situation.
Conclusion
Electric shock from tumble dryer? Damaged or loose live wires touching the body or the tumble dryer frame (potentially via debris), a damaged electrical cord, and bad earthing are all reasons why someone might get a shock from a tumble dryer. As always unplug the tumble dryer before doing any inspection and if in doubt always contact a licensed electrician to help resolve any unknown issues.
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