X-10 Mods

The majority of X-10 units are available only for the USA market where the mains supply is 115 volts at 60 Hz but the UK mains supply is 230 volts 50 Hz. It is however possible to modify some USA modules to operate at 230 volts. Most of the pages on this site provide details of modifications actually performed by the author from X-10 modules bought from Smarthome.

Warning

This information is provided for information only and is not guaranteed to be correct, and I urge you not to attempt these modifications unless you are technically competent. I accept absolutely no responsibility for any modifications you perform or the effects of any such modifications.

Performing these modifications will invalidate your warranty and could render the modules in a dangerous condition and without CE approval. Finally, make sure all installed modules have appropriate fuses and cable to reduce the likelihood of fire.

For further details, please:

Using an Auto-transformer

For those USA X-10 units that take little current, it may be possible to operate them from a 230V to 115V auto-transformer. The autotransformer presents a high impedance to the X-10 signals and so it would normally prevent the X-10 signal from passing. However, if a 0.47 microfarad capacitor is placed across the 230V and 115V windings, this allows the X-10 signals to pass backwards and forwards through the auto-transformer.  If the capacitor is placed across the 0V and 115V windings, then it will further attenuate the X-10 signals and make absolutely certain the X-10 device will not work.

The capacitor must be rated at least 250V AC or 600V DC, and fitting it will usually require that the autotransformer be disassembled, so care must be used.

I have successfully used this technique to get the 115V USA CM15 to operate in the UK.

Reference

The most complete details of 115 volt to 230 volt modifications were on Hans Attersjö's home page, but this has now closed. I have taken some of Hans's work and loaded it onto my server together with corrections identified by readers of these pages and me; I have also included my own modification instructions. The circuit diagrams are courtesy of Steve Bloom.

Modification Reference

The table below gives links to Modification Instructions, Circuit Diagrams, and indicators to modules that I have successfully modified. Links are in the Instr and I Mod columns.

X-10 Modification Reference Table

Links are in the Instr column to the modification instructions.

 Key

• Instr: Link to Modification Information (will open in a new window)
• CirDiag: Link to Circuit Diagrams (will open in a new window)
• I Mod: If Yes, means I have successfully modified the unit.
• Oth: If Yes, means others have reported success; if No, means others have reported failure

Sourcing of Components

Generally, the parts were sourced from Maplin Electronics (but Maplins have now ceased trading) although eBay is now a good source of parts. The one microfarad 250V AC is particularly hard to find as it must be rated at 250V AC minimum. If a 250V DC capacitor is used instead, it will explode. Capacitors are usually rated with a DC voltage and so a 600V DC one should ideally be used. However, these larger capacitors may sometimes be too large to replace the original components.

The Voltage dependant Resistors (VDRs) are also known as Varistors; they present a high resistance at normal voltages but a very low resistance to high voltages, and so these are used for surge suppression in the X-10 modules. If you forget to replace the 150V VDRs, they too will explode when connected to 230V.

Your Turn Now

If you have any success or failure, or any comments to make on these web pages then please let me have the details and I will incorporate them into this reference library.