Why is my Oven is Tripping the electrics during cooking?
Electric Cookers and Ovens can trip the residential circuit breaker when they have an electrical fault. There are broadly three types of electrical fault that can occur in a cooker which can cause the electric to trip.
To help explain we will use standard house wiring as an example, there are three main wires in a home electrical circuit the LIVE or LINE, this is main power wire; the NEUTRAL, this is the return wire; and the GROUND, this is the safety return wire.
The power to your cooking appliances is designed to flow (also known as current) through the LIVE and return through NEUTRAL wires. No current is supposed to flow in the GROUND wire unless there is a problem with the appliance.
A "Short Circuit" is the term used described when the power to the LIVE and NEUTRAL is unhindered, or in technical terms has very low resistance path between them. The common cause of short circuit is when direct link has been made between the cookers body and the LIVE and NEUTRAL. This causes the electricity to flow unhindered back to Neutral, shorting the circuit rather than through its intended route.
Short Circuits are normally accompanied by a bang, this is because resistance can build up in part of the cooker in an unintended location, for example the oven selector switch. This can cause these parts to burn out and go bang in the process.
Ground fault is what happens when the safety GROUND wire conducts current. Residential Circuit breakers (RCB) are designed to trip open the circuit if more than about 0.005A flows in the ground path. Actually, the RCB looks at the current flowing in the LIVE and NEUTRAL and calculates the difference. If this difference is greater than 0.005Amps, the circuit trips open. In this way, the current could flow straight to the earth and the RCB would still detect a ground fault. So, actually, a ground fault happens when some or all of the LINE current flows anywhere besides the NEUTRAL wire.
An 'Open Circuit' is the opposite from a short circuit and is where a current path sees nearly infinite resistance or no circuit.
You will more often experience Open Circuit or Ground Fault in cooker than Short Circuit. Open Circuit faults tend to occur when your cooker element is starting to fail. Typical symptoms include the cooker tripping RCD mid cooking once the element has reached a certain temperature. This is because the heat has caused the faulty wiring inside the element to expand and fail. Over time the integrity of the element will degrade and the fault will occur more frequently.