Rako lighting systems

[plugsandsparks]

Lack of earthing on those lighting ccts is not ideal but in reality you will be looking at double insulated GU10 fitting which do not have provision for an earth connection. However BS7671 recommends earth provision for the future, just in case the fittings are changed for Class 1 (i.e. requiring an earth connection) - TBH it would not stop me doing for myself, by now i would have got the GU10s in scrapped the transformer and experimented with different makes of lamps to get the best dimmable action. It really is trial and error, the main issue is that lamps do fail and are constantly changing manufacturer and design , they are generally getting better but for commercial / non domestic applications the 350mA constant current lamps, simply do not suffer from these issues as the dimming is done by the central driver, not the lamps and Tridonic for example have a great range of drivers and they are very good. So if i want good dimming control, no hassle in the future i go down this road. The last rako i did had the RAK 4 dimmers, early version of yours, and i had a mix of 240V GU10s and 350mA for bathrooms and low level lights / picture lights. The RAK4 did a pretty good job with the GU10s once we got hold of the appropriate lamps. I think but cannot be sure RAKO recommended the lamps, they may not do this anymore but i ordered a shed load and left surplus with client for replacements as and when.

There is plenty of info on-line for the lamps in question, OSram, Megaman, Luceco etc etc for Gu10s
The dimmable lamps need to be stated as suitable for leading edge but as time has gone on, they had got better.

 

[davesparks]

You have a couple of options change all the MR11s for 240V GU10s dimmable and ditch the transformer altogether, trick here is to make sure the dimmable GU10s match the existing dimming module in the Rako.

I'd want to know what the outgoing cable is before recommending a change from ELV to LV. That cable may not be suitable.

 

[plugsandsparks]

TBH, there are a number of "things" that need to be checked, not least where the lamps and cables are going.
All my recommendations are based on helping the Op get an electrician in rather than a Rako specialist.

To the OP, DS is questioning the voltage rating of the outgoing cables from the transformer, you may be lucky and find markings on the cable denoting its characteristics, however at no time am i suggesting you DIY the solution just that its doable for an electrician with no rako knowledge

 

[stalkera]

Thanks for your help on this plugsandsparks and AVO (I think my old man has one of those in the leather case somewhere - from the time when lights were lights), much appreciated. I'll let you know how I get on.