3 way light switch keeps tripping breaker? There are several possible reasons for this including blown bulbs, faulty light fittings, faulty switches and damaged or loose wires. This post will go into seven possible reasons why your 3 way light switch keeps tripping breaker.
How A 3 Way Switch Works
A 3 way switch will have three switches where a light can be turned on or off from any one switch. It is typically wired like in the diagram below.
If a circuit breaker is tripping it means there is something wrong with this system.
Why Does A Circuit Breaker Trip
There are many types of circuit breakers designed to do different things including MCB’s and RCD’s. The main reasons why circuit breakers exist is to protect property from fire and people from potentially fatal electric shocks.
In the standard domestic switchboard circuit breakers will trip if any of these things happen:
- Short circuit
A short circuit occurs when the live wire comes in contact with the neutral wire. The result is an explosive pop which if a breaker doesn’t trip will cause a fire.
- Overload
An overload occurs when there are too many lights on the circuit which causes cables to heat up, melt their insulation and cause a fire. Again, a breaker will trip to stop this happening.
- Earth Leakage
An earth fault occurs when there is contact between the live wire and earth. The result is an electric shock if someone were to make contact with a conductive part.
3 Way Light Switch Keeps Tripping Breaker? – Reason #1
Faulty Light Bulb
A faulty light bulb could have a short circuit which would cause a breaker to trip. The solution to this is to replace the light bulb with a new one.
3 Way Light Switch Keeps Tripping Breaker? – Reason #2
Faulty Light Fitting
If you have replaced the light bulb and the breaker is still tripping then the cause might be with the light fitting itself. The way to tell is to look for signs of melting or burning around the light fitting which would indicate it has burned out as a result of a short circuit.
3 Way Light Switch Keeps Tripping Breaker? – Reason #3
Faulty Light Switch
Faulty switches are commonly why the breaker might trip. The switch mechanism can fail over time due to the mechanical parts inside like springs and plastic wearing down. If the switch feels weird or different to press compared to other switches it might be time to replace them.
3 Way Light Switch Keeps Tripping Breaker? – Reason #4
Someone Has Recently Done Electrical Work
If someone has recently worked on your electrical it’s possible that they have made a mistake. For example, they could have transposed the live and neutral wires when installing a new light. Doing this would cause an RCD to trip. If an electrician has been around recently working on lights it might be a good idea to see what’s up.
3 Way Light Switch Keeps Tripping Breaker? – Reason #5
Loose Or Broken Wires
Loose or broken wires in the switch can cause sparking, eventually leading to a breaker tripping. Loose wires are a common cause of electrical faults. The solution to this would be to make sure that all wires in each switch and light are connected properly.
3 Way Light Switch Keeps Tripping Breaker? – Reason #6
Damaged Cable
Damaged cables can be caused by a range of things including rodents chewing on cables, water intrusion into a circuit or cable cutting on a sharp object (usually in the ceiling). The solution to this is to find out where the broken cable is with an insulation resistance tester and then repair the cable.
3 Way Light Switch Keeps Tripping Breaker? – Reason #7
Overloaded Circuit
Overloads are another reason why breakers trip. If there are too many high wattage lights on one circuit or too small cable size has been used then breakers can trip on overload. The solution is to use a bigger cable or separate the lighting circuits so an overload doesn’t occur.
Next Steps
3 way light switch keeps tripping breaker? There are seven possible reasons why this is occurring including faulty light bulbs, faulty fittings, switches and broken cables. Some other possible causes include an electrical wiring mistake or an overloaded circuit.
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