Why Does My RCCB Keep Tripping? Earth Leakage Explained

How do I know it is the RCCB and not an MCB?

Look at the distribution board without opening it. You can tell them apart at a glance.

• The RCCB is wider than the ordinary breakers next to it, usually taking up the space of two or four of them, and it sits at or near the start of the row.
• It has a TEST button, often marked T. Nothing else on the board has one. That button is the giveaway.
• It may be labelled RCCB, RCD, ELCB or “30mA”. Different names, same job in a home: detecting leakage to earth.
• When it trips, a lot goes dead at once — often the whole flat, or everything except the lights. An MCB trip usually kills one room or one circuit.

If only one room went dark, you are dealing with an MCB and our guide to why an MCB keeps tripping is the right page. If a wide device with a TEST button dropped and took half the flat with it, stay here.

What does earth leakage actually mean?

In plain English: electricity should go out on the live wire and come back on the neutral wire, in equal amounts. The RCCB continuously compares the two. If some current goes out and does not come back, it has left the circuit somewhere else — through damp insulation, through a wet wall, through an appliance body, or through a person — and the RCCB cuts the supply.

Three things follow from that, and they explain almost every RCCB complaint.

• The amount that trips it is tiny. A domestic RCCB is set to react to a leak far smaller than what any appliance normally uses. It is deliberately sensitive, because the number it cares about is the current that hurts a human being, not the current that heats a wire.
• Small leaks add up. Several appliances each leaking a very small amount can total enough to trip the RCCB even though no single one of them is obviously faulty. This is why the trip often seems random and why it starts once a flat accumulates enough old appliances.
• Leakage does not stop anything working. A geyser with a leaking element still heats water. A washing machine with a damp motor still washes. Nothing feels broken, which is why people blame the RCCB.

Why RCCBs trip so often in Delhi homes

There is a strong seasonal and structural pattern here, and knowing it usually points straight at the culprit.

• Monsoon and humidity, by a wide margin. Damp conducts. Moisture in a wall, in a balcony socket, in an outdoor light or in a bathroom fitting gives current a path to earth that simply was not there in April. Trips that begin in July and stop in October are this.
• Geysers. A heating element sits in water, and when it develops a pinhole the leakage begins. A trip that happens only when the geyser is on, in winter, is one of the most common cases in Delhi flats.
• Washing machines and water motors. Wet locations, vibration, and motors that age. A trip that happens only during a wash cycle or only when the pump runs names itself.
• Old aluminium wiring and decayed insulation. In flats built decades ago, insulation gets brittle, especially where it passes near a heat source. Widespread low-level leakage across several circuits usually means the wiring itself is tired — see the signs house wiring needs replacing.
• Water seepage from an upstairs flat or a shared wall. Extremely common in Delhi NCR buildings and often blamed on the appliance below it for months.
• A brand new appliance that pushed the total over the line. The flat was already leaking a little on several circuits; one more addition tipped it. The new appliance is the trigger, not necessarily the fault.

The safe way to find which circuit is leaking

Switches only. No tools, nothing opened, nothing touched inside the board. This is the same first step an electrician takes, and doing it before they arrive shortens the visit.

• 1. Switch off every individual circuit breaker in the row, one by one, leaving the RCCB itself alone.
• 2. Reset the RCCB. If it holds with all circuits off, good — the leak is on one of the circuits, not in the incoming supply or the RCCB itself. If it trips again immediately with everything off, stop here and call an electrician; that is a supply or board fault.
• 3. Switch the circuits back on one at a time, waiting a minute or two between each. The one that drops the RCCB is your leaking circuit.
• 4. Now switch that circuit off again, unplug everything on it, and switch it back on empty. If it holds, plug appliances back in one at a time. The one that trips it is your suspect.
• 5. If the circuit trips with nothing plugged in, the leak is in the fixed wiring, a fixed appliance such as a geyser, or a damp point. That is an electrician job and it does not need a plugged-in appliance to be dangerous.
• 6. Note the weather and the time. Only in the rain, only when the geyser is on, only in the evening — all of these are strong evidence and all of them are free to collect.

Do not do this test standing on a wet floor or with wet hands, and do not force the RCCB back on if it refuses to stay. If it will not reset even with every circuit off, leave it off and call somebody.

When to stop testing and call an electrician

Call the same day if any of these is true.

• The RCCB trips again with every circuit switched off, or refuses to reset at all.
• Anyone has felt a shock or tingle from a tap, an appliance or a metal fitting — read what a shock from a tap or appliance means and treat it as urgent.
• You find damp, seepage or water near any socket, switchboard or light fitting.
• There is a burning or hot-plastic smell, scorching, or a warm switchplate anywhere.
• It trips several times a day, or the tripping is spreading to more circuits over weeks.
• The board has no RCCB at all and you have discovered this while reading. That is worth fixing before anything goes wrong — see what a distribution board upgrade involves.

What an electrician will do is measure the insulation resistance of each circuit to find where the leakage is, test the earthing, and check that the RCCB itself still trips within its rated time. Ask for the leakage source to be named, not just for the RCCB to be swapped — a new RCCB on a leaking circuit trips exactly as often as the old one. For how these visits are usually billed, see electrician charges in Delhi NCR, and home electrical safety tips covers the monthly habits that catch these faults early.