Converting a RR501 X10 module to 230V

The RR501 is a radio transceiver with a built-in appliance module. Its main function is to receive radio signals and send them through the power line to other X10 devices (e.g. lamp modules).

The RR501 can be used with a number of radio controllers, e.g. the "keychain remote", a mini 2-device controller, or a number of multifunction infrared and radio remote controls (to control your TV set and lights from the same remote), or the extremely nifty wall switch that, with a thickness of only about 5mm, looks like it's built into the wall but it can be sticked anywhere without holes or wires.

Converting the built-in appliance module to 230V was too much of a hassle (I'd have to find a relay with the correct form factor), so I just disabled it.

I did the conversion following the instructions at All photos can be enlarged by clicking on them.

This is what the module looks like in its pristine state:
left: original module right: things to be changed

  Since all resistors where 0.5W types already, I only had to exchange six components: Two capacitors, two MOVs, and two resistors.

I bought these parts at a local electronics store:

  • 2x 300V MOV "SIOVS14K300", at 1.02 EUR each (a 275V type would have been sufficient but the shop was out of stock)
  • 1F, 400V capacitor, at 0.92 EUR
  • 0.1F, 400V capacitor, at 0.31 EUR
  • 2x 470kOhm, 0.5W resistor, at 0.10 EUR each
Needless to say that you can get these much cheaper if you order in quantity.

Here's a detail photo of each replacement I made. Of course, I first removed all the old parts and then but in the new ones.

The large capacitor:

left: 2.2/250V capacitor (old) right: 1/400V capacitor (new)

The small capacitor:

left: 0.22/250V capacitor (old) right: 0.1/400V capacitor (new)

Resistor #1:

left: 220k resistor (old) right: 470k resistor (new)

Resistor #2 and MOVs:

left: invisible 220k resistor and old varistors right: 470k resistor and new varistors

The original resistor is hidden behind the large capacitor in the photo on the left. Note how the white wires leading to the relay have been removed in the photo on the right.


left: finished module, open) right: finished module in original case

The modification was an immediate success. As I've said before, I did not bother converting the built-in appliance module, which also made wiring easier. Apart from the "House Code" selection wheel, the panel controls are now useless.

Try this at your own risk.

  Frederik Ramm, 2002-11-01