Safety Notice - 12V Wired Products

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12v Mains-Powered Wired Lights and Components

Please read: This notice contains important safety warnings and other safe usage/installation information about the 12v wired lighting products we stock. We urge you to read this notice carefully and ensure you understand it before purchasing, installing, or using any of our 12v electrical products.

Our 12v wired lighting products are first and foremost a hobby product for adult miniaturists, designed to bring life and light to your dolls houses and 1:12 scale models. They do not run at the same voltage and are not manufactured to the same specifications as regular household lighting or electrical products. They are not designed to be used for long periods of time and should not be used as a supplementary source of lighting in your home.




  • None of our 12v electrical products are suitable for use by children under 14 years of age and children over the age of 14 should be supervised when using these products
  • Never leave a child or vulnerable person unsupervised near a lit dolls house
  • Do not leave 12v wired lighting systems lit for more than 1 hour at a time and allow all the components to thoroughly cool before the next use (for at least 1 hour) by turning the transformer off at the mains and unplugging it
  • Always use with a fuse-protected socket strip (maximum 1.6-amp fast fuse)
  • Do not allow people with reduced physical, sensory, or mental capabilities use electrical products unsupervised
  • Do not allow people with lack of experience or knowledge to install a wiring system or rewire a plug without supervision
  • Always switch the transformer off at the socket and unplug it from the mains wall socket after each use
  • Always test each light (see section on TESTING later in this document) before installation and again after each modification (such as after rewiring a plug or changing a bulb)
  • Always read and follow any safety information or warnings printed on the packaging or provided with the product

Transformers and Bulb Capacity

  • Check that the transformer you are using is 12v and that the voltage marked on the rating label of your transformer matches your mains voltage
  • Do not operate the transformer from an extension lead, it should be plugged directly into a mains socket
  • Never exceed the maximum bulb capacity of your transformer, socket/terminal strip, or fuse (Contact Us with the product code/s if you are unsure)
  • Never touch to the screws on the transformer or the connecting spades from the socket strip whilst the transformer is plugged in.


  • A damaged light fitting or a poorly wired plug can cause fire or give you an electric shock – do not use the product if it has been dropped or if it appears to be damaged in any way
  • Always inspect the product for damage after unpacking and Contact Us if your new Minimum World product has any damage/defects
  • Do not continue to use the light/component if you are in any doubt of the product working normally – switch off and unplug the transformer from the wall socket immediately


  • Some components may get hot during normal use – switch off to cool for a few minutes before handling
  • Do not use in environments with extreme degrees of temperature
  • Do not use near heat sources such as radiators or gas/electric fires
  • Do not use near naked flames
  • Do not expose this product to water or moisture. If you spill any liquid onto the product it can cause serious damage - switch off and unplug the entire wiring system immediately
  • Do not touch any of the components with wet hands


  • Ensure to unplug the transformer from the mains socket before cleaning or modifying any elements in your lighting system (such as changing a bulb)
  • Do not use any type of abrasive pad, chemical cleaning solutions, or any liquids on any of the components in your lighting system

Installation & Usage

  • We strongly recommend using a “round-wire” system with our 12v products (see the section on our ROUND-WIRE SYSTEMS – THE BASICS later in this document for information about this type of lighting system)
  • Always test each light (see section on TESTING later in this document) before installation, after each modification (such as after rewiring a plug or changing a bulb) and again after installation to ensure it is working correctly
  • The wire insulation is thin so always fully uncoil each wire before use and try to avoid wires from other components touching wherever possible
  • Never attempt to install a light into a dolls house while it is plugged in
  • Never attempt to change a bulb while the light is plugged in
  • Plugs for the lights will often need to be removed and then replaced during installation to enable the wires to fit through small holes, please ensure that the two exposed wires are do not touch at any point when you rewire them to the pins in the plug
  • The on/off switch on the socket strips does not turn the system off completely – the transformer will continue to draw electricity from the mains supply while plugged in. Please ensure that the transformer is switched off at the mains socket and unplugged when not in use.
  • All 12v products purchased from Minimum World should be used on a fuse-protected system (maximum 1.6amp fast-blow fuse*) with a transformer that is the appropriate voltage for your country

*We are aware that some other dolls house brands and distributors continue to use 2-amp fuses in their socket strips. While this has been deemed safe practice by most manufacturers of these products, we would strongly urge you to consider switching these fuses out for a lower amp fast-blow fuse to ensure maximum safety when lighting your dolls houses and other scale models.

We have 1.5amp fast-blow fuses available to purchase in 2 sizes which are compatible with most 12v terminal strips.

LT9021 - Pack of 4 Fuses 1.5A are compatible with most 12-socket terminal strips (such as LT9017 commonly used in 1:12 scale)

LTH49006 - Fuses (pk4) are compatible with most 6-socket terminal strips (such as LT9072 commonly used in 1:24 scale)


A round wire system comprises a central 'hub' - a terminal strip (LT9017 pictured) with sockets, a fuse (max 1.6amp fast fuse), and an on-off switch - which connects to a 12v transformer(LT9073 pictured) that is plugged into a mains socket. A 12v light with filament bulb is then plugged into this socket strip, either directly or via extension sockets (LT9013 & LT9015 pictured).

The transformer should be sized according to the number of bulbs being fitted (NOT by the number of light fittings). It is perfectly acceptable to use a higher rated transformer than required (though a voltage regulator is recommended if you are using less than about 5 bulbs in total), but do not exceed the recommended rating on a transformer by adding more bulbs than specified. Our most popular transformer (LT9073) will run up to 32 bulbs - enough for most 6 to 8 room houses.

Please note that while a transformer may power a certain number of bulbs, the maximum bulb capacity of the socket strip and fuse are likely to be less than this. Our most popular socket strip (LT9017) with a 1.5amp fast-fuse (LT9021) has a maximum capacity of 20 bulbs which should not be exceeded, this includes any lights plugged into the terminal strip via extension cords too.

The terminal socket strip should be mounted near the bottom of the outside back wall of the dolls house using the adhesive tape on the back of the strip. The lead-in wire should be connected to the transformer by using the screw terminals (the spade terminals on the end of the wire can be fitted either way round as most dolls house transformers are AC). Make sure the spades are fitted flush against the screws and tighten the screws as tightly as you can manage with an appropriately sized screwdriver to ensure a good connection. Never attempt to touch to the screws or connecting spades whilst the transformer is plugged in.

Before installing any lights, you should temporarily plug them into the terminal strip (one at a time), switch on and monitor for 10 minutes to confirm they are working correctly. Please read our TESTING procedure later in this document for more information on how and when to complete tests and what to look for to detect a fault.

After testing, when you are happy that your lights are working correctly, then you can think about installing them into your dolls house. In order to do this you are most likely going to need to remove the plugs on your lights to enable the wires to pass through small holes leading to the main terminal socket strip. To remove and replace plugs please follow the steps below:

  • Remove the plug from the fitting by holding the plug in one hand while using a small pair of pliers to pull out the pins. This will free the wires which have been anchored by the pins and allow the plug to be completely removed.
  • Pass the wire out through the back wall of your dolls house (or to wherever your terminal socket strip is located).
  • Replace the plug by reversing the method to remove it, being very careful to ensure that the two exposed wires are not touching at any point when you rewind them around the pins in the plug.

For more tips how to install ceiling lights, wall lights and freestanding lights in your dolls house – such as creating groove channels for wires and at what stage to decorate your dolls house – please check out our How-To Guide: Wired Lights Guide.


Always test each light individually before first use, after any modifications (such as changing a bulb or rewiring a plug) and again after final installation.

It is a good idea to keep a note of which light/component you have tested and when so that you can easily identify which element is causing the fault in your system, should one occur. You may want to purchase spare fuses for your socket strip in case you blow any during testing.

Some or all of the components may become "warm" when in use, which is completely normal. None of the components should become very hot (excluding the bulbs). To reduce the risk of burns or electric shock, please take extreme care if touch-testing the temperature of any elements and do not touch the bulbs at any point during testing as they will be extremely hot.

Bulbs often work loose in transit, or with handling, so if one or more bulbs in the light fails to illuminate during your testing then gently tighten/reposition the bulb/s and try again. If this doesn’t fix the problem then replace the bulb and try again. Always leave the light unplugged to cool for at least 10 minutes before attempting to tighten or replace a bulb as the bulbs will become hot when lit.

Please follow the simple steps below on how to test a light:

1) Attach a fused socket strip (e.g. LT9017) to a 12v transformer (e.g. LT9073)     

2) Plug the transformer into a mains wall socket and switch on (the little bulb on the socket strip should not light up – if it does then the fuse has blown and needs to be replaced)

3) Plug the light to be tested into the socket strip and turn on using the switch on the socket strip

4) Observe the light closely for 10 minutes to ensure it is operating correctly and is not overheating or malfunctioning in any way

If any of the following occurs during your testing switch off and unplug all components immediately and Contact Us for advice:

  • Any of the components or wires appear to be melting or producing smoke
  • The fuse on the socket strip blew or the fault light on the socket strip lit up
  • The wire or the light fitting (excluding the bulb) became very hot
  • There is evidence of smoke staining in the bulb/s


As we mentioned earlier, our 12v wired lighting products are first and foremost a hobby product for adult miniaturists, designed to bring life and light to your dolls houses and 1:12 scale models. They do not run at the same voltage and are not manufactured to the same specifications as regular household lighting or electrical products. They are not designed to be used for long periods of time and should not be used as a supplementary source of lighting in your home.

Please note that (except the transformers – which are all CE certified) the 12v products we stock are very low voltage and as such are not covered by the usual CE/UKCA certification that apply to most electrical devices and components. However, there is still a risk of fire, injury, electric shock, or other damage if 12v products are used incorrectly or if used when faulty.

We take great care to ensure that all the electrical products we stock are safe to use and easy to install. We carry out strict quality checks on our own LT Miniature Lighting Co products when they arrive from the manufacturer - including external checks by an independent, qualified electrician. We trust that other brands/manufacturers we stock (such as Dolls House Emporium and Streets Ahead) follow similar procedures with their electrical products - although we cannot guarantee it.

The wires used in dolls house lighting products are very thin to allow the lights to be made in such small scale, this means that there is not as much insulation in the wiring as you would find in a life-size electrical product. So, while the system operates at a very low voltage, it does mean that the lights and components can be prone to overheating and we strongly recommend only turning the lights on for short periods of time (maximum 1 hour) and allowing the system to cool thoroughly between uses.

The intricate and delicate nature of miniature scale models means that wiring and installing these products in your dolls houses can be incredibly fiddly (and as talented as our wonderful customers are, most of you are not qualified electricians!) so there is a small element of risk involved with customers who may install or use these products incorrectly. With that in mind, we ask that you strictly adhere to all the safety warnings, instructions and testing procedures in this document to ensure that you are installing and using these products safely. If in doubt – Test, Test and Test Again! - to ensure each element in your system is operating as it should at each stage of your project.

Alternatively, a much simpler option for adding light to your dolls house is battery-operated LED lighting – no wiring required as each light is operated by its own battery and has a switch on the base – Click here to browse our extensive range of battery-operated lighting!


If you purchased any of the products listed below from Minimum World prior to 31/03/2021 then they may have been supplied with a 2-amp surge-protected fuse:

  • LT9017 - 12 Socket Power Strip (DE074)
  • LT9072 - 6 Socket Power Strip
  • LT9077 - Wiring Kit

For safety reasons, we now recommend a 1.5-amp or 1.6-amp fast-blow fuse to ensure a swift cut-off of the system should a fault occur.

If you have not already received a replacement fuse from us and are still using a 2-amp fuse with any of these products then please stop use of the product immediately and Contact Us (or email with the product code of your item so that we can send you a replacement fuse free of charge.

How to contact us

Please send any queries or comments by email to, by completing a Contact Us form, or by writing to us at the address below:

Minimum World Ltd
Prospect House 2
Loddon Industrial Estate
Little Money Road
NR14 6JD
United Kingdom

If you are unable to resolve your query by these methods then you may reach our customer services team on (+44)(0)1508 528950 between the hours of 10am-3pm on Monday-Friday (excluding public holidays). Please note that any usual network charges will apply to calls from UK mobiles/landlines and additional call charges may apply to calls from international destinations.

This Notice was last updated on 22nd April 2022

Minimum World Ltd | Company Number 4508799 | UK VAT Number 847 1228 25