Can I use lamps from abroad in my home in Japan? 100V, ceiling fittings and the PSE mark

Voltage and frequency in Japan

The Japan National Tourism Organization states that the voltage throughout Japan is uniformly 100 V AC, with a frequency of 50 Hz in eastern Japan and 60 Hz in western Japan, including Nagoya, Kyoto and Osaka. Tokyo is on the 50 Hz side. Wall sockets take a two flat-pin plug, the same shape as ungrounded North American plugs, as KEK, the High Energy Accelerator Research Organization, notes in its guidance for overseas visitors.

For lighting, the frequency rarely matters with modern LED products, which are usually marked 50/60 Hz. It can matter with older fittings and some appliances marked for one frequency only. If you have a home in Tokyo and another in Kyoto or Osaka, check the label before moving a fitting between them.

Lamps from abroad: what to check

Look at the rating label on the lamp itself, and on any separate driver, transformer or plug-in adaptor. That label tells you more than the country you bought it in.

• Input voltage: a label reading 100–240 V will work in Japan with a plug adaptor. A label reading 220–240 V only will not work on 100 V without a step-down transformer, and is usually better replaced.
• 120 V North American lamps: the plug often fits Japanese sockets, but 100 V is lower than the rated voltage. Simple lamps may run dimmer; LED drivers, smart bulbs and dimmers may behave differently. Check the maker's stated input range.
• Bulb base and size: many Japanese bulbs use E26 and E17 bases. Lamps from the UK often use B22 bayonet or E14 bases, so you would need to bring suitable bulbs or change the lamp holder, which is a repair best left to a qualified person.
• Earth (ground): many Japanese sockets have no earth pin. If a lamp has a metal body and an earthed plug, ask an electrician how it can be used safely.
• Frequency: check for 50/60 Hz if you might move the lamp between eastern and western Japan.

The ceiling outlet most rooms already have

Many rooms in Japanese homes have a ceiling outlet known as a hikkake ceiling (引掛シーリング, a twist-lock ceiling outlet), usually round or rectangular. Pendants and ceiling lights made for the Japanese market have a matching plug: you push it in and turn it to lock, following the maker's instructions. No tools or wiring are needed for that step.

Lights from overseas are usually made to be wired directly into a ceiling junction box. In Japan, that wiring is electrical work. Some shops sell adaptors that let an overseas pendant hang from a Japanese ceiling outlet; ask whether a product carries the PSE mark and suits your fitting before you rely on one.

Check weight. Large lanterns, glass shades and heavy chandeliers may exceed the load the ceiling outlet is designed for. The maker of the outlet states that limit; we could not find a single official figure that applies to all of them. A heavier fitting needs a separate support fixed to the ceiling, which is building work.

When you need a licensed electrician

Japan's Electricians Act (Article 3) says that only a person holding a first-class or second-class electrician's licence may carry out electrical work on general electrical facilities, the category that covers the wiring of ordinary homes, apart from minor work set out by ministerial ordinance. The cabinet order under the Act lists minor work that falls outside the definition of electrical work, such as connecting a cord to a plug, socket or ceiling rosette used at 600 V or less.

In practice, these jobs are for a licensed electrician (denki koji shi):

• Wiring a light fitting directly to the ceiling or wall cables.
• Adding, moving or replacing a ceiling outlet, a wall socket or a built-in switch.
• Installing downlights, cove lighting or wall lights that need new wiring.
• Fitting a dimmer to the building's wiring.

Condominium rules and timing

In a condominium, electrical work inside your unit may still need notice to, or approval from, the management association, and contractors may need to register before entering the building. Ask the management company what applies before you book an electrician, and allow time for the paperwork.

This section is general information only. For a specific home, ask the building's management company, a licensed electrician or the relevant office.

The PSE mark: what it is and who it applies to

The Electrical Appliances and Materials Safety Act regulates the manufacture, import and sale of electrical appliances and materials in Japan. According to the Ministry of Economy, Trade and Industry (METI), 457 items are designated under the Act, including 116 "Specified" items (Category A) and 341 non-specified items (Category B); METI's English page lists LED lamps among the Category B examples.

The obligations fall on businesses that manufacture or import these products: they notify METI, ensure the products meet technical requirements, carry out inspections and then label the products with the PSE mark. Selling or displaying for sale an electrical product without the PSE label is prohibited in Japan. METI notes that only individuals living in Japan or companies registered in Japan can file as importers.

For an owner, this means two things. Lamps bought from shops in Japan should carry the PSE mark. And if you bring lamps from abroad for your own home, METI's English pages describe the duties of businesses and do not address that case directly; if you are unsure, ask METI's product safety contact. Do not sell an unlabelled lamp in Japan later, for example when you change the interior or sell the apartment furnished.

Warm light for calm rooms

Once the technical side is settled, choose light by colour as much as by fitting. Bulbs sold in Japan are usually labelled by colour: 電球色 (denkyu-iro) is the warm, incandescent-like tone, 温白色 (on-hakushoku) is a soft middle tone, and 昼白色 or 昼光色 are cooler and whiter. For the warm minimalism many owners want, warm tones in living and sleeping rooms, several low sources instead of one bright ceiling light, and a dimmable bulb where the fitting allows it, make the biggest difference.

Paper and wood soften light further. Our guide to washi lighting covers bulbs and care for Japanese paper lamps.