What Is a DP Switch, and Which Points in Your Home Need One?

DP switch: the short answer

A DP switch, or double pole switch, is a switch that opens two wires at once: the phase (live) and the neutral. An ordinary light switch opens only the phase. That second break is why electricians put DP switches on the points that matter most in a home: the geyser, the air conditioner, the water pump and, in some homes, the washing machine and the oven.

In homes in India the DP switch you will meet is almost always rated 32 amps, and it often has a small indicator lamp that glows while the point is on. It is a switch, not a protective device. It does not trip on overload or short circuit; the MCB in your distribution board does that.

We make DP switches in all three of our ranges, KEMPS, VIZA and VIYONA, at our works in Marol, Andheri East, Mumbai. This guide explains what a DP switch does, how it differs from an SP switch, which points need one, how it is connected and what ours cost at MRP.

What is a DP switch?

A DP switch is a double pole switch: one handle operates two separate sets of contacts, so when you switch it off it disconnects both the phase and the neutral of the appliance at the same time, leaving the appliance with no connection to either supply wire while the switch is off.

The name tells you the count. SP means single pole, one set of contacts. DP means double pole, two sets. You will also see TP and FP on three phase isolators and MCBs, but in a home switch board DP is as far as it goes.

On the back of a DP switch you will find four terminals, usually marked L and N in and L and N out, where a plain 1 way switch has two. Most modular DP switches take 2 modules on the plate, because the contacts and terminals need the space. Our types of electrical switches guide places the DP switch among the 1 way, 2 way, bell push and indicator switches.

DP switch vs SP switch: what is the difference?

The difference between a DP switch and an SP switch is that an SP (single pole) switch breaks only the phase wire, while a DP (double pole) switch breaks the phase and the neutral together, so a DP switch fully isolates the appliance and an SP switch leaves its neutral still connected.

With the phase broken, an SP switch is perfectly safe for lights, fans and most sockets. That is why every light switch in your home is SP. The DP switch adds a second break for appliances where water, metal bodies or heavy current make full isolation worth having.

There is one more reason DP switches exist. If the phase and neutral are ever swapped by mistake, at the meter, in the board or in an old building, an SP switch ends up switching the neutral and the appliance stays live even when switched off. A DP switch breaks both wires, so it isolates either way round. Our phase, neutral and earth guide explains the three wires.

Why is a DP switch used for AC and geyser?

A DP switch is used for an AC and a geyser because both are heavy, fixed appliances with metal parts, and a geyser sits in a wet bathroom, so electricians prefer a switch that breaks phase and neutral together, giving full isolation and a clear on/off point that also works if the wiring polarity is ever wrong.

For an AC, the DP switch is the local isolator. A technician servicing the indoor or outdoor unit switches it off and knows both supply wires are open. Many installers also like the indicator lamp, which shows at a glance whether the AC circuit is energised.

For a geyser, the DP switch usually sits outside the bathroom or high on the wall, away from splashes, and the indicator reminds you the heater is on. Our geyser switch guide covers placement, rating and heating time in detail, and the which MCB for home guide covers the geyser MCB.

For the circuit side of an AC point, from wire size to the MCB, see our MCB for 1, 1.5 and 2 ton AC guide. The DP switch is only one part of that point.

What is a 32A DP switch?

A 32A DP switch is a double pole switch whose contacts are rated to carry up to 32 amps continuously, which leaves plenty of margin for a home geyser, an AC or a pump, and it is the standard DP rating sold in India for home switch boards, so it is the one most electricians ask for.

In our catalogue every DP switch is 32A or 32AX. The X means the switch is also rated for inductive loads such as motors and compressors, which draw a surge as they start. A rating is a maximum, not a target: a 32A switch on a 9 amp geyser is simply running well within its limit.

The switch rating does not decide what the circuit can carry. The wire and the MCB decide that. A 32A switch on a circuit wired and protected for 16A is still a 16A circuit. For every switch and socket rating in one table, see our switch and socket ratings page.

DP switch price: what does a 32A DP switch cost?

A 32A DP switch costs ₹195 to ₹460 MRP in our range, depending on whether it is a conventional surface or concealed type or a modular one with an indicator: the VIYONA 175 surface DP switch is ₹195, and modular versions with an indicator start at ₹295 for the VIZA V225.

VIYONA 176 is a 32A concealed DP switch at ₹205 MRP.

The modular versions cost more because they include the indicator, a 2 module body that clicks into your plate, and a finish that matches the rest of the board. KEMPS K116 is ₹360 in white, and the same switch in grey, KEMPS K516, is ₹392. The VIZA V1250 with indicator is ₹330.

Choose the range your board already uses, so the DP switch matches the plate and the other modules.

DP switch with indicator: is it worth it?

A DP switch with an indicator is worth it on any point you might forget is on, such as a geyser, a pump or an AC, because the small lamp glows whenever the switch is on and shows from across the room that the appliance is still connected and may still be drawing power.

An indicator is cheap insurance against a geyser left on all day or a pump running dry. It draws very little power itself. Every modular DP switch in our range has one: KEMPS K116, VIZA V225 and VIZA V1250.

Treat the lamp as a reminder, not a safety test. A dark indicator does not prove the point is dead; the lamp itself can fail. Before touching any wiring, switch off the MCB and test with a tester. Our switch with indicator guide explains how the lamp works and why one sometimes glows when the switch is off.

Surface, concealed or modular: which DP switch type?

Choose a modular DP switch if your board uses modular plates, a concealed DP switch for a conventional flush board, and a surface DP switch where there is no recessed box at all, such as on an old wall or beside an appliance added later; all three do the same electrical job.

Modular: KEMPS, VIZA and our other modular lines. The switch clips into a 2 module slot on the plate and matches the board’s finish. This is the usual choice in new flats.

Concealed: the VIYONA 176 at ₹205 sits flush in a conventional board. It suits older homes that still use one-piece boards and want a like-for-like replacement.

Surface: the VIYONA 175 at ₹195 mounts on the wall itself. It is a quick fix where a new geyser or AC has been added and nobody wants to cut the wall for a box. Both VIYONA types are on the VIYONA 32 amp DP switch page.

Does a DP switch replace an MCB?

No, a DP switch does not replace an MCB, because a switch never trips on its own: it only opens when someone moves the handle, while an MCB trips automatically on overload or short circuit and protects the cable, so a geyser or AC point needs both an MCB in the board and a switch at the point.

Think of the DP switch as the local on/off and the MCB as the protection. A DP switch also cannot protect against shock from leakage; that is an RCCB’s job, and we do not make RCCBs.

In the board, the geyser and the AC commonly get their own MCB each. We make 10 kA VIYONA MCBs under BIS licence CM/L-2544151. Our isolator vs MCB guide explains the difference between switching and tripping devices, which is the same distinction as DP switch vs MCB.

DP switch connection: how is it wired?

A DP switch is connected with the supply phase and neutral on the two input terminals and the appliance phase and neutral on the two matching output terminals, with the earth wire running straight past the switch to the appliance, never through it; the markings L and N on the back show which terminal is which.

That is the whole idea. The phase goes in at L and out at L, the neutral goes in at N and out at N, and the earth is never switched. A board diagram is on our switch board wiring diagram page.

Replacing a DP switch like for like is the kind of job a careful homeowner may do. First switch off the MCB, then test both wires dead with a tester, note which wire goes where, and tighten each screw firmly: a loose terminal on a 9 to 13 amp geyser load is what makes a switch run hot. Our replace a switch safely guide walks through the steps. Anything new, such as adding a geyser point, is a job for a licensed electrician.

How do you tell if a switch is DP?

You can tell a switch is DP by looking at its back for four terminals marked for line and neutral in and out, by the DP or double pole marking printed on the body, and by its width, since most modular DP switches take two modules on the plate rather than one.

From the front, a DP switch usually has a wider rocker and, in our modular ranges, an indicator lamp. Behind the plate, count the wires: four wires at the switch means DP, two means SP.

Check the rating printed on the body as well. Ours read 32A or 32AX. If a geyser is on a 6A or 10A one way switch, that is worth a look by an electrician; our switch getting hot guide lists the warning signs.

Which points in a home need a DP switch?

In most Indian homes the points that get a DP switch are the geyser, every split or window AC, the water pump, and often an oven, a heater point or a washing machine, while lights, fans and ordinary sockets stay on single pole switches; your electrician decides the final list.

A typical 2BHK might have one per bathroom for the geyser, one per AC, and one for the pump if the building has its own. That is usually three to six DP switches, a small share of the board budget.

Plan them at the wiring stage. Our bathroom electrical points and kitchen electrical points guides show where each heavy point usually goes, and the wire for AC and geyser guide covers the cable behind it.